DE29522188U1 - New photochromic indeno-fused naphthopyrans - Google Patents

Description

G4871DE /FW, PPG Industries, Inc. .*·,.*% **'*., *'\ , * \ . ·*,

1
NEW PHOTOCHROMIC INDENO-ANNELATED NAPHTHOPYRANES

Description of the invention

The present invention relates to certain novel naphthopyran compounds. More particularly, this invention relates to novel photochromic indeno-fused naphthopyran compounds and to compositions and articles containing such novel naphthopyran compounds. Many photochromic compounds exhibit a reversible color change when exposed to light containing ultraviolet rays, such as ultraviolet rays in sunlight or the light from a mercury lamp. When the ultraviolet radiation is interrupted, such photochromic compounds return to their original color or to a colorless state.

Various classes of photochromic compounds have been synthesized and proposed for use in applications where a sunlight-induced reversible color change or darkening is desired. US Patent 3,567,605 (Becker) describes a series of pyran derivatives including certain benzopyrans and naphthopyrans. These compounds are described as derivatives of chromene and are stated to undergo a color change, e.g. from colorless to yellow-orange, upon irradiation with ultraviolet light at temperatures below -30 ⁰ C. It is reported that upon irradiation of the compounds with visible light or upon raising the temperature to above about 0 ⁰ C, the color formation reverts to the colorless state.

US Patent 5,066,818 describes that various 3,3-diaryl-3H-naphtho[2,l-b]pyrans have desirable photochromic properties, e.g. good tintability and acceptable brightening for eyeglasses and other

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applications. The '818 patent also discloses, by comparative examples, the isomeric 2,2-diaryl-2H-naphtho[l,2-b)pyrans, which are reported to require unacceptably long periods of time to clear after activation.

U.S. Patent 3,627,690 describes photochromic 2,2-disubstituted 2H-naphtho[l,2-b]pyran compositions containing small amounts of either a base or a weak to moderate acid. It is reported that the addition of either an acid or a base to the naphthopyran composition increases the lightening rate of the colored naphthopyrans, making them useful in eye protection applications, e.g., sunglass. It is further reported herein that the lightening rate of 2H-naphtho[l,2-b]pyrans without the above-mentioned additives ranges from several hours to many days until complete reversal is achieved. US Patent 4,818,096 discloses violet-blue colored photochromic benzo- or naphthopyrans having a phenyl group in the alpha position to the oxygen of the pyran ring with a nitrogen-containing substituent in the ortho or para positions.

The present invention relates to novel substituted naphthopyran compounds having a substituted or unsubstituted indeno group, wherein the 2,1 positions of the indeno group are fused to the f-side of the naphtho moiety of the naphthopyran and the pyran ring is substituted at the 3-position. It was unexpectedly found that these compounds exhibit a bathochromic shift of the wavelength in the visible spectrum at which the maximum absorption of the activated (colored) form of the photochromic compound, i.e. Lambda max (Vis), occurs, resulting in activated colors ranging from orange to blue-gray. In addition, these compounds demonstrated high molar absorption (or molar extinction coefficient) in the UV region, an acceptable lightening rate without the addition of

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Acids or bases, a high activated intensity and a high coloring speed.

In particular, the substituents at the 3-position of the pyran ring can be selected from the group consisting of: (i) the unsubstituted mono-, di- and trisubstituted aryl groups phenyl and naphthyl, (ii) the unsubstituted mono- and disubstituted aromatic heterocyclic groups pyridyl, furanyl, benzofuran-2-yl, benzofuran-3-yl, thienyl, benzothien-2-yl, benzothien-3-yl, wherein the substituents of these aryl and aromatic heterocyclic groups in parts (i) and (ii) are each selected from the group consisting of hydroxy, amino, MOnO(C ₁ -C ₆ ) alkyl amino, DUC^C^alkylamino, piperidino, morpholino, pyrryl, C ₁ -C ₆ -alkyl, C ₁ -C ₆ -chloroOaIkYl, C ₁ -C ₆ -fluoroalkyl, C ₁ -C ₆ -alkoxy, mono(C ₁ -C ₆ )alkoxy(C ₁ -C ₄ )alkyl, acryloxy, methacryloxy, chlorine and fluorine; (iii) the groups represented by the following graphic formulas:

wherein A can be carbon or oxygen and D can be oxygen or substituted nitrogen, provided that when D is substituted nitrogen, A is carbon, said nitrogen substituents being selected from the group consisting of hydrogen, C ₁ -C ₆ -alkyl and C ₂ -C ₆ -alkyl; each R ₈ is C ₁ -C ₆ -alkyl, C ₁ -C ₆ -alkyl, hydroxy, chlorine or fluorine, R ₉ and R ₁₀ are each hydrogen or C ₁ -C ₆ -alkyl and ρ is the integer O, 1 or 2; (iv) C ₁ -C ₆ -alkyl, C ₁ -C ₆ -chloroalkyl, C ₁ -C ₆ -fluoroalkyl, C ₁ -C ₆ -alkoxy(C _r C ₄ )alkyl, C ₃ -C ₆ -cycloalkyl,

Mono^-C^alky! (C ₃ -C ₆ )cycloalkyl,

GBM4871/F1/F, PPG Industries, Inc.

Chi or(C ₃ -C ₆ ) cycloalkyl and FlUOr(C ₃ -C ₆ )cycloalkyl; and (ν) the group represented by the following graphic formula:

wherein X may be hydrogen or C ₁ -C ₄ alkyl and Z may be selected from the unsubstituted mono- and disubstituted members of the group consisting of naphthyl, phenyl, furanyl and thienyl, the group substituents in this part (v) being each C ₁ -C ₄ alkyl, C ₁ -C ₄ alkoxy, fluorine or chlorine; or (vi) the substituents at the 3-position of the pyran ring together form fluoren-9-ylidene, mono- or disubstituted fluoren-9-ylidene or a member selected from the group consisting of saturated C ₃ -C ₁₂ spiro-monocyclic hydrocarbon rings, e.g. cyclopropylidene, cyclobutylidene, cyclopentylidene, cyclohexylidene, cycloheptylidene, cyclooctylidene, cyclononylidene, cyclodecylidene, cycloundecylidene, cyclododecylidene; saturated C ₇ -C ₁₂ -spirobicyclic hydrocarbon rings, eg bicyclo[2.2.1]heptylidene, ie norbornylidene, 1,7,7-trimethylbiyclo[2.2.1]heptylidene, ie bornylidene, bicyclo-[3.2.1]octylidene, bicyclo[3.3.1]nonan-9-ylidene, bicyclo[4.3.2]undecane and saturated C ₇ -C ₁₂ -spirotricyclic hydrocarbon rings, eg tricyclo[2.2.1.0 ²⁶ ]hept-ylidene, tricyclo[3.3.1.3 ³⁷ ]decylidene, ie

adamantylidene and tricyclo[5.3.1.1 ²⁶ ]dodecylidene, wherein each of these substituents of the fluoren-9-ylidene is selected from the group consisting of C ₁ -C ₄ -ARyI, C ₁ -C ₄ -ALkOXy, fluorine and chlorine.

Detailed description of the invention

In recent years, photochromic plastic materials, especially plastic materials for optical applications, have been the subject of considerable attention. In particular, photochromic

GBM4871/F1/F, PPG Industries, Inc.

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Plastic eye lenses have been investigated due to the weight advantage they offer over glass lenses. Photochromic lenses for vehicles such as cars or airplanes have also been of interest due to the potential safety benefits such lenses offer.

In accordance with this invention, it has now been discovered that certain novel indeno[2,l-f]naphtho[l,2-b]pyrans can be prepared which have an activated color ranging from orange to blue-gray, an acceptable lightening rate, a high activated intensity, and a high coloring rate. These compounds can be described as indeno-fused [l,2-b]naphthopyrans having certain substituents at the 3-position of the pyran ring. Certain substituents can additionally be present at carbon atoms number 5, 6, 7, 8, 9, 10, 11, 12, or 13 of the compound. These compounds can be described by the following graphic formula in which the letters a through η define the positions of the naphthopyran ring and the numbers represent the numbers of ring atoms of the naphthopyran:

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In the graphic formula I, R ₁ and R ₂ together may form an oxo group, a spiroheterocyclic group containing 2 oxygen atoms and 3 to 6 carbon atoms including the spiro carbon atom, which may be represented by the expression (-O-(C ₂ -C ₅ -alkanediyl)-O-) e.g. spiro-1,3-dioxolane-2, spiro-1,3-dioxane-2 etc., or R ₁ and R ₂ may each be hydrogen, hydroxy, C ₁ -C ₆ -alkyl, C ₃ -C ₇ -cycloalkyl, allyl, phenyl, monosubstituted phenyl, benzyl, monosubstituted benzyl, chlorine, fluorine, the group -C(O)W, wherein W is hydroxy, C ₁ -C ₆ -alkyl, C ₁ -C ₆ -alkoxy, phenyl, monosubstituted phenyl, Amino, mono(C ₁ -C ₆ )alkylamino or di(C ₁ -C ₆ )alkylamino, for example dimethylamino, methylpropylamino etc.

or R ₁ and R ₂ can each be the group -OR ₅ , wherein R ₅ is C ₁ -C ₆ alkyl, phenyl (C ₁ -C ₃ alkyl, mono(C ₁ -C ₆ )alkyl-substituted phenyl (C ₁ -C ₃ )alkyl, FnOnO(C ₁ -C ₆ )alkoxy-substituted phenyl (C ₁ -C ₃ alkyl, C ₁ -C ₆ -alkoxy(C ₂ -C ₄ )alkyl, C ₃ -C ₇ -cycloalkyl, mono(C ₁ -C ₄ )alkyl-substituted C ₃ -C ₇ -cycloalkyl, C ₁ -C ₆ -chloralkyl, C ₁ -C ₆ -fluoroalkyl, allyl, the group -CH(R ₆ )X, wherein R ₆ is hydrogen or C ₁ -C ₃ -ARyI and X is CN, CF ₃ or COOR ₇ and R ₇ is hydrogen or C ₁ -C ₃ -ARyI or R ₅ is the group -C(O)Y, wherein Y is hydrogen, C ₁ -C ₆ -ARyI, C ₁ -C ₆ -ARoXy, the unsubstituted mono- or disubstituted aryl group, phenyl or naphthyl, phenoxy, mono- or di(C ₁ -C ₆ )alkyl-substituted phenoxy, mono- or di-(C ₁ -C ₆ )alkoxy-substituted phenoxy, amino, MOnO(C ₁ -C ₆ )alkyl ami no, di(C ₁ -C ₆ )alkylami no, phenylamino, mono- or di-(C ₁ -C ₆ )blkyl-substituted phen-

G4871DE1/F, PPG Industries, Inc.

nylamino, or mono- or di-C1-C6-alkoxy-substituted phenyl amino, where the substituents of the above-mentioned phenyl, benzyl and aryl groups are C ₁ -C ₆ -alkyl or C ₁ -C ₆ -alkyloxy.

In particular, R ₁ and R ₂ are each selected from the group consisting of hydrogen, hydroxy, C ₁ -C ₄ alkyl, C ₃ -C ₆ cycloalkyl, chlorine, fluorine and the group -OR ₅ , wherein R ₅ is C ₁ -C ₃ -ARyI, phenyl (C ₁ -C ₂ alkyl, InOnO(C ₁ -C ₃ )alkyl-substituted phenyl(C ₁ -C ₃ )alkyl, mono(C!-C ₃ )alkoxy-substituted phenyl(C ₁ -C ₃ )alkyl, C ₁ -C ₃ -alkoxy(C ₂ -C ₄ )alkyl, C ₁ -C ₃ -ChI oral kyl, C ₁ -C ₃ -fluoroalkyl, the group -CH(R ₆ )X, wherein R ₆ is hydrogen or C ₁ -C ₂ -ARyI and X is CN or COOR ₇ is where R ₇ is hydrogen or C ₁ -C ₂ -ARyI or R ₅ is the group -C(O)Y where Y is hydrogen, C ₁ -C ₃ -ARyI, C ₁ -C ₃ -alkoxy, phenyl, naphthyl, the monosubstituted aryl groups phenyl or naphthyl, phenoxy, mono- or di(C ₁ -C ₃ alkyl-substituted phenoxy, mono(C ₁ -C ₃ )alkylamino, phenylamino, mono- or di(C _{1 -C 3} )alkyl-substituted phenylamino or mono- or di(C ₁ -C ₃ alkyl-substituted phenylamino, each of these aryl group substitutes being C ₁ -C ₃ -ARyI or C ₁ -C ₃ -alkoxy. It is particularly preferred if R ₁ and R ₂ are each hydrogen, hydroxy, C ₁ -C ₄ -ARyI or the group -OR ₅ , where R ₅ is C ₁ -C ₃ -ARyI.

R ₃ and R ₄ in graphic formula I can each be C ₁ -C ₆ -ARyI, C ₁ -C ₆ -alkoxy, chlorine or fluorine, m and η are each the integers O, 1 or 2, R ₃ can be located on the ring atoms of the naphthopyran number 10 and/or number 11 and R ₄ can be located on the ring atoms number 6 and/or number 7. When m and η are 2, the R ₃ (and R ₄ ) substituents can be the same or different. It is particularly preferred when R ₃ and R ₄ are each C ₁ -C ₃ -ARyI, C ₁ -C ₃ -ARoXy or fluorine, m and η are each the integers 0 or 1, R ₃ is located on the ring atom number 11 and R ₄ is located on the ring atom number 6. It is most preferred when R ₃ and R ₄ are C ₁ -C ₃ -ARyI and C ₁ -C ₃ -ARoXy, respectively, and m and η are each the integers 0 or 1.

G4871DE1/F, PPG Industries, Inc. ,** **- **■ -"*- ·-■**

B and B' of the graphic formula I can each be selected from the group consisting of: (i) the unsubstituted mono-, di- and trisubstituted aryl groups phenyl and naphthyl, (ii) the unsubstituted mono- and disubstituted aromatic heterocyclic groups pyridyl, furanyl, benzofuran-2-yl, benzofuran-3-yl, thienyl, benzothien-2-yl, benzothien-3-yl, where the substituents of these aryl and aromatic heterocyclic groups in parts (i) and (ii) are each selected from the group consisting of hydroxy, amino, MOnO(C ₁ -C ₆ )alkyl amino, di(C ₁ -C ₆ )alkyl amino, piperidino, morpholino, pyrryl, C ₁ -C ₆ -ARyI, C ₁ -C ₆ -chloroalkyl, C ₁ -C ₆ -fluoroalkyl, C ₁ -C ₆ -ALkOXy. Mono(C ₁ -C ₆ )alkoxy(C ₁ -C ₄ )alkyl, acryloxy, methacryloxy, chlorine and fluorine; (iii) the groups represented by the following graphic formulas:

15 UA HB

wherein A can be carbon or oxygen and D can be oxygen or substituted nitrogen, provided that when D is substituted nitrogen, A is carbon, said nitrogen substituents being selected from the group consisting of hydrogen, C ₁ -C ₆ alkyl and C ₂ -C ₆ alkoxy; each R ₈ is Ci-C 6 alkyl, C ₁ -C ₆ alkoxy, hydroxy, chlorine or fluorine, R ₉ and R ₁₀ are each hydrogen or C ₁ -C ₆ alkyl and ρ is the integer O, 1 or 2; (iv) C ₁ -C ₆ -alkyl, C 1 -C 6 -chloroalkyl, C ₁ -C ₆ -fluoroalkyl, C ₁ -C ₆ -alkoxy(C ₁ -C ₄ )alkyl, C ₃ -C ₆ -cycloalkyl, MOnO(C ₁ -C ₆ )alkoxy(C ₃ -C ₆ )cycloalkyl, mono(C ₁ -C ₆ )alkyl(C ₃ -C ₆ )cycloalkyl, chloro(C ₃ -C ₆ )cycloalkyl and fluoro(C ₃ -C ₆ )cycloalkyl; and (v) the group represented by the following graphic formula:

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II C

wherein X in the graphic formula HC can be hydrogen or C ₁ -C ₄ -AlKyI and Z in the graphic formula IIC can be selected from the unsubstituted mono- and disubstituted members of the group consisting of naphthyl, phenyl, furanyl and thienyl, wherein the group substituents in this part (v) are each C ₁ -C ₄ -AlKyI, C ₁ -C ₄ -AlkOXy, fluorine or chlorine; or (vi) B and B' together form fluoren-9-ylidene, mono- or disubstituted fluoren-9-ylidene or a member selected from the group consisting of saturated C ₃ -C ₁₂ spiromonocyclic hydrocarbon rings, e.g. cyclopropylidene, cyclobutylidene, cyclopentylidene, cyclohexylidene, cycloheptylidene, cyclooctylidene, cyclononylidene, cyclodecylidene, cycloundecylidene, cyclododecylidene; saturated C ₇ -C ₁₂ -spirobicyclic hydrocarbon rings, eg bi cyclo[2.2.1]heptylidene, ie norbornylidene, 1,7,7-trimethylbiyclo[2.2.1]heptylidene, ie bornylidene, bicyclo[3.2.1]octylidene, bicyclo[3.3.1]nonan-9-ylidene, bicyclo[4.3.2]undecane and saturated C ₇ -C ₁₂ -spirotricyclic hydrocarbon rings, eg tricyclo[2.2.1.0 ²⁶ ]heptylidene, tricyclo[3.3.1.3 ³⁷ ]decylidene, ie adamantylidene and tricyclo[5.3.1.1 ²⁶ ]dodecylidene, wherein each of these substituents of the fluoren-9-ylidene is selected from the group consisting of C ₁ -C ₄ -alkyl, C ₁ -C ₄ -AlkOXy, fluorine and chlorine.

It is particularly preferred if B and B' are each selected from the group consisting of: (i) phenyl, monosubstituted phenyl and disubstituted phenyl, preferably substituted in the meta and/or para positions; (ii) the unsubstituted mono- and disubstituted aromatic heterocyclic groups furanyl, benzofuran-2-yl, thienyl and benzothien-2-yl, each of these substituents of the phenyl and aromatic heterocyclic groups being selected from the group consisting of:

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consisting of hydroxy, amino, mono(C ₁ -C ₃ ) arylamino, di(C ₁ -C ₃ )alkylamino, piperidino, morpholino, pyrryl, C ₁ -C ₃ -alkyl, C ₁ -C ₃ -chloroalkyl, C _{1 -C 3 -alkoxy} , MOnO(C ₁ -C ₃ )alkoxy(C _{1 -C 3} )alkyl, fluorine and chlorine; (iii) the groups represented by the graphic formulas πα and UB, wherein A is carbon and D is oxygen, R ₈ is C ₁ -C ₃ -alkyl or C ₁ -C ₃ -alkoxy, R ₉ and R ₁₀ are each hydrogen or C ₁ -C ₃ -alkyl and ρ is the integer O or 1; (iv) C ₁ -C ₄ -ARyI and (v) the group represented by graphic formula IIC wherein X is hydrogen or methyl and Z is phenyl or monosubstituted phenyl, said phenyl substituents being selected from the group consisting of C ₁ -C ₃ -ARyI, C ₁ -C ₃ -ALkOXy and fluorine or (vi) B and B ¹ taken together form fluoren-9-ylidene, monosubstituted fluoren-9-ylidene or a member selected from the group consisting of saturated C ₃ -C ₈ spiromonocyclic hydrocarbon rings, saturated C ₇ -C ₁₀ spirobicyclic hydrocarbon rings and saturated C ₇ -C ₁₀ spirotricyclic hydrocarbon rings, said fluoren-9-ylidene substituents being selected from the group consisting of C ₁ -C ₃ -alkyl, C ₁ -C ₃ -ALkOXy, fluorine and chlorine.

It is most preferred when B and B ¹ are each selected from the group consisting of (i) phenyl, mono- and disubstituted phenyl, (ii) the unsubstituted, mono- and disubstituted aromatic heterocyclic groups furanyl, benzofuran-2-yl, thienyl and benzothien-2-yl, each of said substituents of the phenyl and aromatic heterocyclic groups being selected from the group consisting of hydroxy, C ₁ -C ₃ -ARyI, C ₁ -C ₃ -ALkOXy, fluorine and chlorine; and (iii) the group represented by graphic formula IIA wherein A is carbon and D is oxygen, R ₈ is C ₁ -C ₃ -ARyI or C ₁ -C ₃ -ARoXy, R ₉ and R ₁₀ are each hydrogen or C ₁ -C ₃ -ARyI and ρ is the integer O or 1; or (iv) B and B ¹ taken together form fluoren-9-ylidene, adamantylidene, bornylidene, norbornylidene or bicylclo[3.3.1]nonan-9-ylidene.

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• · » I

Compounds represented by graphic formula I having substituents R ₃ , R ₄ , B and B ¹ as previously described can be prepared by the following reactions A through E. Methods for preparing compounds represented by graphic formula I containing substituents R ₁ and R ₂ as previously described are contained in reactions D and E. Compounds represented by graphic formulas V, VA or VB are either purchased or prepared by Friedel-Craft procedures shown in reaction A using appropriately substituted or unsubstituted benzoyl chlorides of graphic formula IV with a commercially available substituted or unsubstituted benzene compound of graphic formula III. See the publication Friedel-Crafts and Related Reactions, George A. Olah, Interscience Publishers, 1964, Volume 3, Chapter XXXI (Synthesis of aromatic ketones) and "Regioselective Friedel-Crafts Acylation of 1,2,3,4-Tetrahydroquinoline and Related Nitrogen Hetercycles: Effect on NH Protective Groups and Ring Size" by Ishihara, Yugi et al, J. Chem. Soc, Perkin Trans. 1, pages 3401-3406, 1992.

In reaction A, the compounds represented by graphic formulae III and IV are dissolved in a solvent such as carbon disulfide or methylene chloride and reacted in the presence of a Lewis acid such as aluminum chloride or tin tetrachloride to give the corresponding substituted benzophenones represented by graphic formulae V (VA in reaction B or VB in reaction C). R and R' represent possible substituents previously described with reference to graphic formula I.

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Reaction A

III

COCl

AlCl

In reaction B, the substituted or unsubstituted ketone represented by graphic formula VA, in which B and B' can represent groups other than substituted or unsubstituted phenyl as shown in graphic formula V, is reacted with sodium acetylide in a suitable solvent such as anhydrous tetrahydrofuran (THF) to form the corresponding propargyl alcohol represented by graphic formula VI. Propargyl alcohols having B or B ¹ groups other than substituted and unsubstituted phenyl can be prepared from commercially available ketones or ketones prepared by reacting an acyl halide with a substituted or unsubstituted benzene, naphthalene or heterocyclic compound. Propargyl alcohols having a B or B' group represented by graphic formula IIC can be prepared by the methods described in U.S. Patent 5,274,132, column 2, lines 40 to 68.

Reaction B

The

B B'

VA

THF

O _x /C=CH

^BB1

VI

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In reaction C, a substituted or unsubstituted benzophenone represented by graphic formula VB is reacted with an ester of succinic acid such as dimethyl succinate represented by graphic formula VII. Addition of the reactants to a solvent, e.g. toluene, containing potassium 1-butyl oxide or sodium hydride as a base gives the half ester of the Stobbe condensation represented by graphic formula VIII. If R ₃ and R ₄ of the benzophenone are not identical, i.e. not structurally symmetrical, a mixture of cis and trans half esters is formed, requiring further purification to isolate a distinguishable isomer. The half ester (VIII) undergoes cyclodehydration in the presence of acetic anhydride to form acetoxynaphthalene represented by graphic formula IX. This product is hydrolyzed in an aqueous alcoholic solution of a base such as sodium hydroxide, followed by treatment with aqueous hydrochloric acid (H ⁺ ) to form the carboxynaphthol represented by graphic formula X.

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12
Reaction C

(RO

■3-&Iacgr;&tgr;&igr;

t-BuOK

Toluene

(R ₄ ) _n

Acetic anhydride

( _R3 )

COOH

1. NaOH H ₂ O/Alcohol

2. H ⁺

_{CO2CH3 ​}

IX

In reaction D, the carboxynaphthol represented by graphic formula X is cyclized to a hydroxy-substituted, benzane-inert fluorenone represented by graphic formula XI by heating to about 160 to about 220 ^° C in the presence of an acid such as phosphoric acid. See the article by FG Baddar et al., in J. Chem. Soc, page 986, 1958. An alternative method for preparing the compound represented by graphic formula XI is described by CF. Koelsch in the Journal of Organic Chemistry, volume 26, page 2590, 1961.

The coupling of the compound represented by the graphic formula XI with a propargyl alcohol represented by the graphic formula VI in the presence of a catalytic amount of an acid, e.g. dodecylbenzenesulfonic acid (DBSA), leads to the indeno-

G4871DE1/F, PPG Industries, Inc. /V. '*'

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fused naphthopyran represented by graphic formula IA. Reduction of the compound represented by graphic formula XI by the Wolff-Kishner reduction results in a compound represented by graphic formula XIA. Coupling of the compound represented by graphic formula XIA with a propargyl alcohol represented by graphic formula VI results in the indeno-fused naphthopyran represented by graphic formula IB. Replacement of the hydrogen atoms in graphic formula IB with alkyl groups, e.g. R ₁ and R ₂ , is accomplished by reaction of compound IB with trialkylaluminum to produce the compound represented by graphic formula IC.

Compounds similar to the compounds represented by graphic formula IC, in which R ₁ and R ₂ are alkoxy rather than alkyl, or R ₁ and R ₂ taken together form a spiro-heterocyclic group containing 2 oxygen atoms and 3 to 6 carbon atoms including the spiro carbon atom, can be prepared by reacting the compound represented by graphic formula IA with an alcohol or a diol, respectively, in the presence of a catalytic amount of an acid.

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• · ♦ ·

14
Reaction D

( _R3 ),

COOH

phosphoric acid

warmth

Wolff-Kishner
reduction

XI

HO. X=CH C

In reaction E, further processes for the preparation of compounds with different R ₁ and R ₂ substituents are described by the graphic

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Formula I. Starting from the compound represented by graphic formula IA, reduction with lithium aluminum hydride (LAH) leads to the compound represented by graphic formula ID. Other methods for reducing the carbonyl group are described in the text "The Chemistry of the Carbonyl Group", Chapter 11, Saul Patai, Editor, 1966, Interscience Publishers.

Reaction of the compound represented by graphic formula ID with an acyl chloride having the potential substituent R ¹ results in the compound represented by graphic formula IE. Another way of introducing different R ₁ and R ₂ substituents into the compound represented by graphic formula IA is by reacting compound (IA) with a Grignard or lithium reagent having the potential substituent R to give the compound represented by graphic formula IF. Subsequent reactions of the compound represented by graphic formula IF with an alcohol having the potential substituent R ¹ in the presence of an acid such as hydrochloric acid results in a compound represented by graphic formula IG.

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16
Reaction E

.0

l.Grignard(RMgX)

Compounds represented by the graphic formula I can be used in applications in which organic photochromic substances can be used, such as vision correction lenses for eyes, plano lenses, face shields, goggles, visors, camera

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lenses, windows, windshields for cars, aircraft and car windows e.g. sunroofs, side windows and rear windows, plastic films and panes, textiles and coatings, e.g. for coating compositions such as paints and verification markings on security documents, e.g. documents such as banknotes, passports and driving licenses where authenticity and verification of authenticity may be desired. Naphthopyrans, which are represented by the graphic formula I, show color transitions from colorless to colors in the range from orange to blue-gray.

Examples of naphthopyran compounds included within the scope of the invention are the following:

(a) 3-(4-Methoxyphenyl)-3-(3-methyl-4-methoxyphenyl)-13-hydroxyindeno[2,l-f]naphtho[l,2-b]pyran;

(b) 3,3-Di(4-methoxyphenyl)-13-hydroxy-13-methyl-indeno[2,lf]naphtho[l,2-b]pyran;

(c) 3 -(4-Methoxyphenyl)-3-(2,3-dihydrobenzofur-5-yl)-13-hydroxy 13-methyl-indeno[2,l-f]naphtho[l,2-b]pyran;

(d) 3-(4-Methoxyphenyl)-3-(2,3-dihydrobenzofur-5-yl)-13-acetoxy-6,II-dimethoxy-13-methyl-indeno[2,l-f]naphtho[l,2 -b]pyran;

(e) 3,3-Di(4-methoxyphenyl)-6,II-dimethyl-13-methoxy-indeno[2,lf]naphtho[l,2-b]pyran;

(f) 3,3-Di(4-methoxyphenyl)-6-methyl-II-fluoro-13,13-diethoxyindeno[2,l-f]naphtho[l,2-b]pyran;

(g) 3,3-Di(4-methoxyphenyl)-6,11-dimethyl-13-(1-methyl ethyl)-13-hydroxy-indeno[2,l-f]naphtho[l,2-b]pyran;

(h) 3-(4-Methoxyphenyl)-3-(3,4-dimethoxyphenyl)-6,11-dimethyl 13,13-dipropyl-indeno[2,l-f]naphtho[l,2-b]pyran; and

(i) 3,3-Di(4-methoxyphenyl)-6,11-dimethyl-13-butyl-13-hydroxyindeno[2,l-f]naphtho[l,2-b]pyran.

G4871DE1/F, PPG Industries, Inc. .·"..*% ** * · · * * * 1 * 11 *

It is contemplated that the organic photochromic naphthopyrans of the present invention may be used alone or in combination with other naphthopyrans of the present invention or in combination with one or more other suitable complementary photochromic materials, i.e., organic photochromic compounds having at least one activated absorption maximum within a range between 400 and 700 nanometers or substances containing them, or may be incorporated, i.e., dissolved or dispersed, into a polymeric organic host material used to prepare photochromic articles which, when activated, change color to a suitable hue.

In cases other than the examples or where otherwise indicated, all numerical values indicating wavelength values of components or reaction conditions as used herein shall in all cases be modified by the term "about."

Examples of complementary organic photochromic compounds include other naphthopyrans, benzopyrans, phenanthropyrans, spiro(benzindoline)naphthopyrans, spiro(indole in)benzopyrans, spiro(indole in)naphthopyrans, spiro(indoline)quinopyrans, spiro(indoline)pyrans, spiro(indoline)naphthoxazines, spiro(indoline)pyridobenzoxazines, spiro(benzindoline)pyridobenzoxazines, spiro(benzindoline)naphthoxazines, spiro(indoline)benzoxazines, and mixtures of such photochromic compounds.

Any of the photochromic substances described herein may be used in amounts (or in a ratio) such that an organic host material to which the organic compounds or mixtures of compounds are applied or into which they are incorporated exhibits a desired resulting color, i.e., a substantially neutral color when activated with unfiltered sunlight,

G4871DE1/F, PPG Industries, Inc. **..*% ******** ?**t &iacgr;***

i.e. a colour as neutral as possible, relative to the colour of the activated photochromic compounds.

A neutral gray color exhibits a spectrum that shows relatively equal absorption in the visible region between 400 and 700 nanometers. A neutral brown color exhibits a spectrum in which the absorption in the 400 to 550 nanometer range is moderately greater than in the 550 to 700 nanometer range. An alternative way to describe color is in terms of its chromaticity coordinates, which describe the quality of a color in addition to its luminance factor, i.e., its chromaticity. In the CIE system, the chromaticity coordinates are obtained by setting up the ratios of the tristimulus values to their sum, i.e., x=X/(X+Y+Z) and y=Y/(X+Y+Z). Colors described in the CIE system can be drawn on a chromaticity diagram, usually as a plot of the chromaticity coordinates χ and y. See pages 47 - 52 in Principles of Color Technology, by F.W. Billmeyer, Jr., and Max Saltzmann, Second Edition, John Wiley and Sons, N.Y. (1981). As used herein, a near neutral color is one in which the chromaticity coordinate values of "x" and "y" for the colors are within the following ranges (D65 illuminant): x = 0.260 to 0.400, y = 0.280 to 0.400 following activation to 40 percent visible light transmittance by exposure to solar radiation (air mass 1 or 2).

The amount of photochromic substance or composition containing the same applied to or incorporated into a host material is not critical provided that a sufficient amount is used to produce a photochromic effect which upon activation can be detected by the naked eye. In general, such an amount may be described as a photochromic amount. The particular amount used will often depend on the intensity of the desired color upon irradiation thereof and the process used.

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used to introduce or apply the photochromic substances. Typically, up to a certain limit, the more photochromic substance is applied or introduced, the greater the color intensity.

The relative amounts of the above-described photochromic compounds used will vary and depend in part on the relative intensities of the colors of the activated species of such compounds and on the final color desired. In general, the amount of any photochromic substance incorporated into or applied to a photochromic optical host material will range from about 0.05 to about 1.0, e.g., from 0.1 to about 0.45 milligrams per square centimeter of surface area to which the photochromic substance(s) is incorporated or applied.

The photochromic substances of the present invention can be applied to or incorporated into a host material, such as a polymeric organic host material, by various methods described in the art. Such methods include dissolving or dispersing the photochromic substance within the host material, e.g., casting in situ by adding the photochromic substance to the monomeric host material prior to polymerization; imbibing the photochromic substance into the host material by immersing the host material in a hot solution of the photochromic substance or by thermal transfer; providing the photochromic substance as a discrete layer between adjacent layers of the host material, e.g., as part of a polymeric film; and applying the photochromic substance as part of a coating that is disposed on the surface of the host material. It is intended that the term "imbibing" or "imbibing" refers to the permeation of the photochromic substance into the host material alone, the solvent-assisted transfer of the photo-

G4871DE1/F, PPG Industries, Inc. ·*.**. »*'.***· ******

chrome substance into a porous polymer, vapor phase transfer and other such transfer mechanisms.

Compatible (chemical and color-related) colorations, i.e. dyes, can be applied to the host material to achieve a more aesthetically pleasing result, for medical reasons or fashion reasons. The particular dye selected will vary and depend on the above-mentioned requirements and the desired results. In one embodiment, the dye can be selected to complement the color produced by the activated photochromic substance, e.g. to achieve a more neutral color or to absorb a particular wavelength of incident light. In another embodiment, the dye can be selected to impart a desired hue to the host material when the photochromic substance is in a non-activated state.

The host material is usually transparent, but may be translucent or even opaque. The host material need only be transparent to that part of the electromagnetic spectrum which activates the photochromic substance, i.e. the wavelength of ultraviolet light which produces the open form of the substance and the part of the visible spectrum which includes the maximum absorption wavelength of the substance in its UV-activated form, i.e. the open form. Preferably, the color of the host material should not be such that it masks the color of the activated form of the photochromic substances, i.e. such that the change in color can be immediately recognized by the observer. It is particularly preferred if the host material is a solid transparent or optically clear material, e.g. materials suitable for optical applications such as plane and ophthalmic lenses, windows, automobile windows, e.g. windshields, aircraft windows, plastic windows, polymeric films, etc.

G4871DE1/F, PPG Industries, Inc. ·· . ♦·. ,**.***« **"·****

Examples of polymeric organic host materials that can be used with the photochromic substances or compositions described herein include: polymers, i.e., homopolymers and copolymers of polyol(allyl carbonate) monomers, diethylene glycol dimethacrylate monomers, diisopropenylbenzene monomers, ethoxylated bisphenol A dimethacrylate monomers, ethylene glycol bismethacrylate monomers, poly(ethylene glycol)bismethacrylate monomers, ethoxylated phenol methacrylate monomers, and monomers of acrylates of alkoxylated polyhydric alcohols, such as ethoxylated trimethylolpropane triacrylate monomers; Polymers, i.e. homopolymers and copolymers of polyfunctional, e.g. mono-, di- or multifunctional acrylate and/or methacrylate monomers, poly(C-C -alkyl methacrylates), such as poly(methyl methacrylate), poly(oxyalkylene dimethacrylate), poly(alkoxylated phenol methacrylates), cellulose acetate, cellulose triacetate, cellulose acetate propionate, cellulose acetate butyrate, poly(vinyl acetate), polyvinyl alcohol), polyvinyl chloride), polyvinylidene chloride), polyurethanes, thermoplastic polycarbonates, polyesters, poly(ethylene terephthalate), polystyrene, poly(alpha-methyl styrene), copoly(styrene methyl methacrylate), copoly(styro-!acrylonitrile), polyvinyl butyral and polymers, i.e. homopolymers and copolymers of Diallylidene pentaerythritol, in particular copolymers with polyol(allyl carbonate) monomers, e.g. diethylene glycol bistallyl carbonate) and acrylate monomers.

Transparent copolymers and mixtures of transparent polymers are also suitable as host materials. Preferably, the host material is an optically clear, polymerized organic material made from thermoplastic polycarbonate resins such as carbonate-linked resins derived from bisphenol A and phosgene, such as the material sold under the brand LEXAN, a polyester such as the material sold under the brand MYLAR, a poly(methyl methacrylate), such as the material sold under the brand PLEXIGLAS, polymers of a poly-

G4871DE1/F, PPGIndustries, Inc.

lyol(allyl carbonate) monomer, especially diethylene glycol bis(allyl carbonate), this monomer being sold under the trademark CR-39 and polymers of copolymers of a polyol(allyl carbonate), e.g., diethylene glycol bis(allyl carbonate), with other copolymerizable monomeric materials such as copolymers with vinyl acetate, e.g., copolymers of 80-90 percent diethylene glycol bis(allyl carbonate) and 10-20 percent vinyl acetate, preferably 80-85 percent of bis(allyl carbonate) and 15-20 percent vinyl acetate and copolymers with a polyurethane having a terminal diacrylate functionality as described in U.S. Patents 4,360,653 and 4,994,208 and copolymers with aliphatic urethanes whose terminal position contains allyl or acrylyl functional groups as described in U.S. Patent 5,200,483, polyvinyl acetate), polyvinyl butyral, polyurethane, polymers of members of the group consisting of diethylene glycol dimethacrylate monomers, diisopropenylbenzene monomers, ethoxylated bisphenol A dimethacrylate monomers, ethylene glycol bismethacrylate monomers, poly(ethylene glycol) bismethacrylate monomers, ethoxylated phenol methacrylate monomers, and ethoxylated trimethylolpropane triacrylate monomers; cellulose acetate, cellulose propionate, cellulose butyrate, cellulose acetate butyrate, polystyrene, and copolymers of styrene with methyl methacrylate, vinyl acetate, and acrylonitrile.

Most particularly, the photochromic naphthopyrans of the present invention are intended for use with optical organic resin monomers used to prepare optically clear polymerizates, i.e., materials suitable for optical applications such as flat and ophthalmic lenses, window and automobile glass. Such optically clear polymerizates may have a refractive index ranging from about 1.48 to 1.75, e.g., from about 1.495 to about 1.66. Particularly included are optical resins sold by PPG Industries, Inc. under the designation CR-307 and CR-407.

G4871DE1/F, PPG Industries, Inc. **. ^· ^&bgr; . «**. ***. ·

The present invention is further described in the following examples, which are intended to be illustrative only, since numerous modifications and variations thereof will become apparent to those skilled in the art.
5

Example 1 Step 1

Potassium 1-butyl oxide (75 grams, 0.67 mole) was added to a reaction flask containing 200 milliliters (mL) of toluene. The reaction flask was equipped with an overhead stirrer, dropping funnel, and reflux condenser with nitrogen inlet. The contents of the reaction flask were heated to reflux temperature and a mixture of benzophenone (91 grams, 0.5 mole), dimethyl succinate (90 grams, 0.62 mole), and toluene (100 grams) were added over a half hour period. The resulting pasty mixture was refluxed for an additional 2 hours, cooled, and approximately 400 mL of water was added and mixed well. The aqueous layer was separated, acidified with dilute hydrochloric acid, and extracted with 200 mL of toluene. The solvents. Toluene and remaining t-butanol were removed using a rotary evaporator to give a nearly quantitative yield of crude half-ester 4,4-diphenyl-3-methoxycarbonyl-3-butenoic acid. This material was not purified but was used directly in the next step.

step 2

The crude half-ester from step 1 was added to a reaction flask containing 200 mL of toluene. Acetic anhydride (100 grams) and anhydrous sodium acetate (15 grams) were added and the mixture was heated at reflux for 17 hours. The mixture was cooled and the toluene solvent was removed on a rotary evaporator.

G4871DE1/F, PPG Industries, Inc. *·./*. «**.·**· *****

The resulting residue was dissolved in 200 mL of methylene chloride and stirred. Water (200 mL) was added, followed by the slow addition of solid sodium carbonate until carbon dioxide evolution ceased. The methylene chloride layer was separated and washed with water.

The solvent, methylene chloride, was removed with a rotary evaporator to give a viscous oil containing primarily 1-phenyl-2-methoxycarbonyl-4-acetoxynaphthalene. This material was not further purified but used directly in the next step.

step 3

The oily l-phenyl^-methoxycarbonyl^-acetoxynaphthalene from step 2 was added to a reaction flask containing 400 mL of methanol.

2 ml of concentrated hydrochloric acid was added and the mixture was heated to reflux. After approximately 4 hours, the volume of the mixture was reduced to half using a rotary evaporator. As the mixture cooled, the product began to crystallize. The resulting crystals were vacuum filtered, washed with fresh methanol and dried. The recovered product, 100 grams, had a melting point of 174-176 ^° C and a nuclear magnetic resonance (NMR) spectrum which showed that the product had a structure consistent with 4-phenyl-3-methoxycarbonyl■1-naphthol.

Step 4

The 4-phenyl-3-methoxycarbonyl-naphthol, 100 grams, from Step 3 was added to a reaction flask containing 350 mL of a 10 wt% sodium hydroxide solution and 50 mL of methanol. The mixture was heated to reflux for one hour, cooled, then slowly poured into a beaker containing approximately one liter of cold (approximately 4°C) dilute hydrochloric acid. Approximately 90 grams of the resulting

G4871DE1/F, PPG Industries, Inc. *« ··'. /*.,*·, ·".."·

Crystalline product l-phenyl-4-hydroxy-2-naphthalic acid with a melting point of 210 - 212°C was collected by vacuum filtration.

Step 5

35 grams of 1-phenyl ^-hydroxy^-naphthalene acid from step 4 was added to a reaction flask containing 35 grams of an 85 wt% phosphoric acid solution. The resulting mixture was heated to 190-200 ^° C and held at this temperature for one hour. During this time, a deep red colored solid product formed. The mixture was cooled and 200 mL of water was added. The solid was broken up with a spatula, filtered, and washed sequentially with water, 5 wt% aqueous sodium carbonate solution, and water. 18 grams of the red colored product 5-hydroxy-7H-benzo[C]-fluoren-7-one was recovered by vacuum filtration.

Step 6

5-Hydroxy-7H-benzo[C]-fluoren-7-one (6 grams) from step 5 was added to a reaction flask containing l,l-di(4-methoxyphenyl)-2-propyn-l-ol (6 grams) and 100 mL of toluene. The resulting mixture was stirred and heated to 50 ^° C. 3 drops of dodecylbenzenesulfonic acid were added and the reaction mixture was kept at 50 ^° C for 5 hours. After the reaction mixture was cooled to room temperature, it was filtered and the collected filtrates were washed three times with 5 wt% aqueous sodium hydroxide solution. The toluene solvent was removed with a rotary evaporator and the desired product crystallized upon addition of acetone to the residue. The solid was vacuum filtered, washed with fresh acetone and dried to give 6.2 grams of a red-orange colored product with a melting point of 190 - 191 ⁰ C. An NMR showed that

G4871DE1/F, PPG Industries, Inc. .*..'*. /".·*"· · ;· :

the product has a structure consistent with 3,3-di(4-methoxyphenyl)-13-oxo-indeno[2,l-f]naphtho[l,2-b]pyran.

Step 7

Three grams of the 3,3-di(4-methoxyphenyl)-13-oxo-indeno[2,l-f]naphtho[l,2-b]pyran from step 6 was added to a reaction flask containing 50 mL of anhydrous diethyl ether. Small amounts of lithium aluminum hydride were added to the stirred mixture until the red-orange color completely disappeared. The reaction mixture was stirred for an additional 10 minutes, quenched with a small amount of methanol, and poured into 200 mL of 5 wt% aqueous hydrochloric acid. The organic layer was separated, washed with water, filtered, and the solvent, diethyl ether, was removed with a rotary evaporator. Addition of approximately 10 milliliters of a 2:1 mixture of hexane:ethyl acetate to the solid caused crystallization of the desired product. The recovered crystals were washed with a small amount of a 2:1 mixture of hexane-ethyl acetate and dried to give 2.6 grams of the product with a melting point of 127-129°C. An NMR spectrum showed that the product has a structure consistent with 3,3-di(4-methoxyphenyl)-13-hydroxy-i ndeno[2,1-f]naphtho[l,2 b]pyran.

Example 2

The procedure of Example 1 was followed except that in Step 7, three grams of 3,3-di(4-methoxyphenyl)-13-oxo-indeno[2,lf]naphtho[l,2-b]pyran was added to a reaction flask containing 50 mL of anhydrous tetrahydrofuran. The mixture was cooled on an ice bath and protected from moisture with a nitrogen blanket while an excess of methyl Grignard reagent was added to the reaction with stirring. After an additional 10 minutes of stirring, 200 mL of a

G4871DEI/F, PPG Industries, Inc. ,··..*·. ,"··"· ·*";:**&idigr;

5 wt.% aqueous hydrochloric acid was added and the organic layer was separated and washed with water. The solvent tetrahydrofuran was removed with a rotary evaporator. Addition of approximately 10 milliliters of a 2:1 mixture of hexane:ethyl acetate to the residue caused crystallization of a non-photochromic material. This material was separated by filtration. The filtrate was chromatographed on a silica column using a 3:1 mixture of hexane:ethyl acetate as eluant. The desired product which crystallized from ether was filtered and dried to give 0.7 grams of a product having a melting point of 125-126 ^° C. An NMR spectrum showed that the product has a structure consistent with 3,3-di(4-methoxyphenyl)-13-hydroxy-13-methyl-indeno[2,1-f]naphtho[l,2-b]pyran.

Example 3

The procedure of Example 1 was followed except that in step 6, l-(2,3-dihydrobenzofur-5-yl)-l-(4-methoxyphenyl)-2-propyn-l-ol was used instead of l,l-di(4-methoxyphenyl)-2-propyn-l-ol. The resulting product, 3-(4-methoxyphenyl)-3-(2,3-dihydrobenzofur-5-yl)-13-oxo-indeno[2,lf]naphtho[l,2-b]pyran, was used instead of 3,3-di(4-methoxyphenyl)-13-oxo-indeno[2,lf]naphtho[l,2-b]pyran in step 7 as described in Example 2. The resulting diastereomeric mixture was crystallized from an ether-hexane mixture, filtered and dried. The crystals obtained, 3.7 grams, melted within a temperature range of 121-135°C. An NMR spectrum showed that the product has a structure consistent with 3-(4-methoxyphenyD-3-(2,3-dihydrobenzofur-5-yl)-13-hydroxy-13-methyl-indeno[2,lfjnaphtho-[l,2-b]pyran
is.

G4871DE1/F, PPG Industries, Inc. /·,/*· «"';·"*: \'*;&idiagr;"&idiagr;

Example 4

The procedure of Example 1 was followed except that in Step 1, 200 grams of toluene was used instead of 100 grams in dissolving the 4,4'-dimethylbenzophenone (105 grams, 0.5 mole) used instead of benzophenone to prepare 4,4-di(4-methylphenyl)-3-methoxycarbonyl-3-butenoic acid. This Stobbe-Shield bester was used in Step 2 to prepare 100 grams of l-(4-methylphenyl)-2-methoxycarbonyl■ 4-acetoxy-6-methylnaphthalene having a melting point of 144-146°C. Step 3 of the procedure of Example 1 was omitted. In step 4, l-(4-methylphenyl)-2-methoxycarbonyl-4-acetoxy-6-methylnaphthalene was used instead of 4-phenyl-3-methoxycarbonyl-1-naphthol to produce l-(4-methylphenyl)-4-hydroxy-6-methyl-2-naphthalene with a melting point of 210-213 ⁰ C. In step 5, 100 grams of this product was used instead of 1-phenyl-4-hydroxy-2-naphthalene and mixed with xylene (250 grams) and 250 grams of an 85 weight percent phosphoric acid solution. The stirred mixture was heated at reflux in a 1 L flask equipped with a Dean-Stark trap for 20 hours to produce 90 grams of 3,9-dimethyl-5-hydroxy-7H-benzo[C]-fluoren-7-one, of which 2.0 grams were used in step 6 with 3.0 grams of l-(2,3-dihydrobenzofur-5-yl)-l-(4-methoxyphenyl)-2-propyn-l-ol. The resulting product, 3-(4-methoxyphenyl)-3-(2,3-dihydrobenzofur-5-yl)-6,ll-dimethyl-13-oxo-indeno[2,lf]naphtho[l,2-b]pyran
was prepared in step 7 as described in Example 2 except that an ether-hexane mixture was used to crystallize the product. The recovered product, 1.2 grams, had a melting point of 198-200 ^° C. An NMR spectrum shows that the product has a structure consistent with 3-(4-methoxyphenyl)-3-(2,3-dihydrobenzofur-5-yl)-13-hydroxy-6,11,13-trimethyl-indeno[2,1-f]naphtho[l,2-b]pyran.

G4871DE1/F, PPG Industries, Inc. ,**.>; ^? ·. · J * J \ '** ·

30
Example 5

The procedure of Example 4 was followed except that in Step 6, 10 grams of l,l-di(4-methoxyphenyl)-2-propyn-l-ol was reacted with 10 grams of 3,9-dimethyl-5-hydroxy-7H-benzo[C]-fluoren-7-one to produce 16 grams of a product having a melting point of 227-229°C. An NMR spectrum showed that the product has a structure consistent with 2,3-di(4-methoxyphenyl)-6,ll-dimethyl-13-oxo-indeno[2,lf]naphtho[l,2-b]pyran
consistent. In step 7, 10 grams of the pyran product from step 6 was reacted with an excess of methyl Grignard and the desired product was crystallized from methanol instead of an ether-hexane mixture. The recovered product, 8 grams, had a melting point of 233-235°C. An NMR spectrum showed that the product has a structure consistent with 3,3-di(4-methoxyphenyl)-6,11,13-trimethyl-13-hydroxy-indeno[2,1f]naphtho[l,2-b]pyran.

Example 6

The procedure of Example 5 was followed except that in step 7 an excess of ethyl Grignard reagent rather than methyl Grignard reagent was reacted with 3 grams of 3,3-di(4-methoxyphenyl)-6,11-dimethyl-13-oxo-indeno[2,lf]naphtho[l,2-b]pyran to produce 1.4 grams of a crystalline product having a melting point of 153-155 ^° C. An NMR spectrum showed that the product has a structure consistent with 3,3-di(4-methoxyphenyl)-6,11-dimethyl-13-ethyl-13 hydroxy-indeno[2,lf]naphtho[l,2-b]pyran.

Example 7

The procedure of Example 5 was followed except that in step 7 an excess of isopropyl Grignard reagent was used instead of methyl Grignard with 3 grams of 3,3-di(4-methoxyphenyl)-6,ll-dimethyl-13-oxo-

G4871DE1/F, PPG Industries, Inc.

• * · i

indeno[2,lf]naphtho[l,2-b]pyran to produce 1.7 grams of a crystalline product having a melting point of 209-210 ⁰ C. An NMR spectrum showed that the product has a structure consistent with 3,3-di(4-methoxyphenyl)-6,ll-dimethyl-13-(l-methylethyl)-13-hydroxy-&igr;ndeno[2,lf]naphtho[l,2-b]pyran.

Example 8

The procedure of Example 5 was followed except that in step 7 an excess of t-butyl Grignard reagent instead of methyl Grignard was reacted with 3 grams of 3,3-di(4-methoxyphenyl)-6,ll-dimethyl-13-oxoindeno[2,1f]naphtho[l,2-b]pyran to give 1.0 gram of a crystalline product having a melting point greater than 240 ^° C. An NMR spectrum showed the product to have a structure consistent with 3,3-di(4-methoxyphenyl)-6,ll-dimethyl-13-(1,1-dimethylethyl)-13-hydroxy-indeno[2,1-f]naphtho[l,2-b]pyran.

Example 9

The procedure of Example 5 was followed except that in step 7 an excess of η-butyllithium reagent instead of methyl Grignard was reacted with 3 grams of 3,3-di(4-methoxyphenyl)-6,ll-dimethyl-13-oxoindeno[2,lf]naphtho[l,2-b]pyran to give 1.0 gram of a crystalline product having a melting point of 148-150 ^° C. An NMR spectrum shows that the product has a structure consistent with 3,3-di(4-methoxyphenyl)-6,ll-dimethyl-13-butyl-13-hydroxy-indeno[2,lf]naphtho[l,2-b]pyran.

Comparison example 1 30

4-Phenyl-3-methoxycarbonyl-1-naphthol (2 grams) from Step 3 of Example 1 and l,l-di(4-methoxyphenyl)-2-propyn-l-ol (2 grams) were added to

G4871DE1/F, PPG Industries, Inc.

a reaction flask containing 100 milliliters (mL) of toluene. The resulting mixture was stirred and heated to 40 ⁰ C. 2 drops of dodecylbenzenesulfonic acid were added and the reaction mixture was kept at 4O ⁰ C for 3 hours. After the reaction mixture was cooled to room temperature, an equal volume of water was added. The organic layer was separated and the solvent toluene was removed with a rotary evaporator. The resulting residue was chromatographed on silica using a 2:1 mixture of hexane:ethyl acetate as eluant. The photochromic fractions were combined, the solvent was evaporated and crystallization of the desired product was induced by a hexane/diethyl ether mixture. The recovered crystals were dried and filtered to give 2 grams of the product with a melting point of 168-169 °C. An NMR spectrum showed that the product has a structure consistent with 2,2-di(4-methoxyphenyl),5-methoxycarbonyl,6-phenyl-[2H]-naphtho[l,2-b]pyran.

Example 10 Part A

The tests were conducted with selected photochromic naphthopyrans imbibed into test square polymers. The test square polymers were made from a diethylene glycol bis(allyl carbonate) composition manufactured by PPG Industries under the designation CR-307 optical resin and measured \ inch (0.6 centimeters) x 2 inches (5.1 centimeters) x 2 inches (5.1 centimeters). The test squares were imbibed using the following procedure. Each naphthopyran was dissolved in a 1:9 mixture of ethyl eel:toluene to form a 10 weight percent solution. The solution was then spin coated onto the test squares and allowed to dry. The samples were then heated in a convection oven at 135-155°C for a time sufficient to imbibe the photochromic material into the test squares.

G4871DE1/F, PPG Industries, Inc. «. *^ .·*..·*. ₄ *. »**,

drate. After cooling, the ethylcellulose/toluene resin film was removed from the test squares by washing with acetone. The residence time in the oven for the test squares was adjusted to imbibe amounts of the naphthopyran compounds that would give comparable absorbance values at Lamda max (UV) of the individual compounds.

part B

The photochromic test squares of Part A were tested for rate of photochromic response on an optical bench. Prior to the optical bench tests, the photochromic test squares were exposed to an ultraviolet light having a wavelength of 365 nanometers for approximately 15 minutes to activate the photochromic compounds and then placed in a heated oven at 76°C for approximately 15 minutes to bleach the photochromic compounds. The test squares were then cooled to room temperature, exposed to fluorescent room light for 2 hours, and then kept covered at 75°F (23.9°C) for at least 2 hours prior to the optical bench tests.

The optical bench contains a 150 watt xenon arc lamp, a tungsten lamp, power supplies for both lamps, collecting lenses necessary to maintain collimated light beams from both lamps, a remote controlled shutter, a copper sulfate bath which acts as a heat sink for the arc lamp, a Schott WG 320 nm cut-off filter which removes short wavelength radiation, neutral density filters, a sample holder into which the sample to be examined is inserted, a photopic filter, light detector and radiometer assembly, a strip chart recorder and a means of maintaining the alignment of the above-mentioned components during the examination.

G4871DE1/F,PPGIndustries, Inc. ,··..*'. .**..**. ***..**.

The change in optical density (ΔOD) of a sample was determined by placing a photochromic test sample in the bleached state in the sample holder, adjusting the transmittance scale to 100 percent, opening the shutter of the xenon lamp to generate ultraviolet radiation to bring the sample from the bleached state to an activated (darkened) state, and measuring the transmittance through this sample. The transmittance was measured by directing a beam of light from the mercury lamp at a small angle perpendicular to the surface of the sample, through the sample and to a photopic filter, light detector, and radiometer assembly. The photopic filter transmits wavelengths such that the detector approximates the response of the human eye and produces an output signal that is processed by the radiometer. The change in optical density was calculated using the formula ΔOD. OD=Iog(100ATa), where #Ta is the percentage of transmittance in the activated state and is the logarithm to the base of ten.

Δ 0D/min, which represents the sensitivity of the response of the photochromic compound to UV light, was measured during the first five (5) seconds of UV exposure and then expressed per minute. Saturation optical density (OD) was recorded under identical conditions to Δ OD/min except that UV exposure was continued for 20 minutes. Lambda max (Vis) is the wavelength of the visible spectrum at which maximum absorption of the activated (colored) form of the photochromic compound occurs in the test squares. Bleaching rate (T V _z ) is the time interval in seconds in which adsorption of the activated form of the naphthopyran in the test squares reaches half of the highest absorption at room temperature (75 ⁰ F, 23.9 ⁰ C) after removal of the source of activating light. Results for the compounds of the examples are given in Table 1 .

G4871DE1/F, PPG Industries, Inc. ·· ··.. ·*.”*% s ^M * s***

Part C

The respective products of the example compounds were dissolved in diethylene glycol dimethyl ether. The concentration of the resulting solution was approximately 0.5 milligrams per milliliter. Each solution was examined in a UV spectrometer to determine the wavelength in the ultraviolet region near the visible spectrum at which the absorption of the photochromic compound occurs. These results are given as lambda (λ) max (UV) in Table 2.

Lambda max (Vis) is the wavelength in the visible spectrum at which the maximum absorption of the activated (colored) form of the photochromic compound occurs in a test square. The Lambda max (Vis) wavelengths given in Table 2 were determined by testing the photochromic square test polymerizates of Part A on the optical bench of Part B.

The molar absorption or molar extinction coefficient (ε) given in Table 2 corresponds to the absorption of the photochromic compound in a diethylene glycol dimethyl ether solution at λ max in the UV spectrum (A) divided by the path length of the spectrophotometric cell (b) multiplied by the concentration of the solution of the photochromic compound in moles per liter (M), according to the formula: ε = A/bM. The molar absorption was measured in a UV spectrometer with ^2x10-3 molar solutions of the selected example compounds in a 0.1 centimeter quartz cell.

G4871DE1/F, PPG Industries, Inc. *· **■ ·■* 1 ΔOD (a Bleaching speed 36 saturation speed T V ₂ (see) Table 0.89 207 Connection Sensitive!tat 0.79 119 Example ΔOD/min 0.77 265 1 1.13 0.74 401 2 1.20 0.73 362 3 0.89 0.64 237 4 0.67 . 0.64 264 5 0.78 0.61 313 6 0.72 0.65 206 7 0.66 0.38 152 8th 0.57 9 0.73 VB1 0.49

The data given in Table 1 show that each compound tested according to the present invention has a higher ΔOD at saturation, i.e. activated intensity and a higher discoloration rate, i.e. sensitivity (ΔOD/min) compared to Comparative Example (CE) 1. The example compounds also show an acceptable bleaching rate, i.e. lightening rate.

871DE1/F, PPG Industries, Inc. *, * λ max (nm) 37 # · · · λ max (nm) UV Table 2 · · * Vis Molar Ab (main peak) Connection 361 sorption (ε) λ max (nm) 562 Example 359 Vis 560 359 (secondary peak) 570 1 360 9666 436 575 2 359 9186 435 570 3 360 438 572 4 359 10,165 443 577 5 362 438 576 6 359 9677 439 575 7 347 439 517 CX) 9471 440 9 6174 439 VB1 420

The data presented in Table 2 show that each compound of the present invention tested exhibits a higher λ max UV and λ max Vis of the main peak, demonstrating a bathochromic shift in the UV and visible spectrum, and exhibits a higher molar absorption or molar extinction coefficient (ε) in the UV spectrum compared to VB 1.
10

The present invention has been described with respect to specific details of certain embodiments thereof. It is not intended that such details be considered limitations on the scope of the invention, except to the extent that such limitations are included in the appended claims.

• · ♦

Claims (18)

1. A naphthopyran compound having a substituted or unsubstituted indeno group, wherein the 2,1 positions of the indeno group are fused to the f-side of the naphtho moiety of the naphthopyran and the pyran ring is substituted at the 3-position. 2. Naphthopyran compound according to claim 1, characterized in that the substituents at the 3-position of the pyran ring are selected from the group consisting of: a) the unsubstituted mono-, di- and trisubstituted aryl groups phenyl and naphthyl; b) the unsubstituted mono- and disubstituted aromatic heterocyclic groups pyridyl, furanyl, benzofuran-2-yl, benzofuran-3-yl, thienyl, benzothien-2-yl, benzothien-3-yl, wherein the substituents of these aryl and aromatic heterocyclic groups in (i) and (ii) are each selected from the group consisting of hydroxy, amino, mono(C ₁ -C ₆ )alkylamino, di(C ₁ -C ₆ )alkylamino, piperidino, morpholino, pyrryl, C ₁ -C ₆ alkyl, C ₁ -C ₆ chloroalkyl, C ₁ -C ₆ fluoroalkyl, C ₁ -C ₆ alkoxy, mono(C ₁ -C ₆ )alkoxy(C ₁ -C ₄ )alkyl, acryloxy, methacryloxy, chlorine and fluorine; c) the groups represented by the following graphic formulas:


wherein A is carbon or oxygen and D is oxygen or substituted nitrogen, provided that when D is substituted nitrogen, A is carbon, said nitrogen substituents being selected from the group consisting of hydrogen, C ₁ -C ₆ alkyl and C ₂ -C ₆ acyl; each R 8 is C ₁ -C ₆ alkyl, C 1 -C ₆ alkoxy, hydroxy, chlorine or fluorine, R ₉ and R ₁₀ are each hydrogen _or C ₁ -C ₆ alkyl and p is the integer 0, 1 or 2; d) C ₁ -C ₆ -alkyl, C ₁ -C ₆ -chloroalkyl, C ₁ -C ₆ -fluoroalkyl, C ₁ -C ₆ -alkoxy(C ₁ -C ₄ )alkyl, C ₃ -C ₆ -cycloalkyl, mono(C ₁ -C ₆ )alkoxy(C ₃ -C ₆ ) cycloalkyl, mono(C ₁ -C ₆ ) alkyl(C ₃ -C ₆ )cycloalkyl, chloro(C ₃ -C ₆ )cycloalkyl and fluoro(C ₃ -C ₆ )cycloalkyl; and (e) the group represented by the following graphic formula:


wherein X is hydrogen or C ₁ -C ₄ alkyl and Z is selected from the unsubstituted mono- and disubstituted members of the group consisting of naphthyl, phenyl, furanyl and thienyl, wherein the group substituents are C ₁ -C ₄ alkyl, C ₁ -C ₄ alkoxy, fluorine or chlorine; or f) the substituents at the 3-position of the pyran ring together form fluoren-9-ylidene, mono- or disubstituted fluoren-9-ylidene or a member selected from the group consisting of saturated C ₃ -C ₁₂ spiro-monocyclic hydrocarbon rings, saturated C ₇ -C ₁₂ spirobicyclic hydrocarbon rings and saturated C ₇ -C ₁₂ spirotricyclic hydrocarbon rings, each of said substituents of the fluoren-9-ylidene being selected from the group consisting of C ₁ -C ₄ alkyl, C ₁ -C ₄ alkoxy, fluorine and chlorine. 3. Naphthopyran compound represented by the following graphic formula:


wherein, a) R ₁ and R ₂ together form an oxo group, a spiro-heterocyclic group containing 2 oxygen atoms and 3 to 6 carbon atoms including the spiro carbon atom, or R ₁ and R ₂ are each hydrogen, hydroxy, C ₁ -C ₆ alkyl, C ₃ - C ₇ cycloalkyl, allyl, phenyl, monosubstituted phenyl, benzyl, monosubstituted benzyl, chlorine, fluorine, the group -C(O)W, wherein W is hydroxy, C ₁ -C ₆ alkyl, C ₁ -C ₆ alkoxy, phenyl, monosubstituted phenyl, amino, mono(C ₁ -C ₆ )alkylamino or di(C ₁ - C ₆ )alkylamino, or R ₁ and R ₂ are each the group -OR ₅ , wherein R ₅ is C ₁ -C ₆ alkyl, phenyl (C ₁ -C ₃ )alkyl, mono(C ₁ -C ₆ )alkyl-substituted phenyl(C ₁ -C ₃ )alkyl, mono(C ₁ -C ₆ )alkoxy-substituted phenyl(C ₁ -C ₃ )alkyl, C ₁ -C ₆ -alkoxy(C ₂ -C ₄ )alkyl, C ₃ -C ₇ -cycloalkyl, mono(C ₁ -C ₄ )alkyl-substituted C ₃ -C ₇ -cycloalkyl, C ₁ -C ₆ -chloroalkyl, C ₁ -C ₆ -fluoroalkyl, allyl, the group -CH(R ₆ )X, wherein R ₆ is hydrogen or C ₁ -C ₃ -alkyl and X is CN, CF ₃ or COOR ₇ and R ₇ is hydrogen or C ₁ -C ₃ -alkyl or R ₅ is the group -C(O)Y, wherein Y is hydrogen, C ₁ -C ₆ -alkyl, C ₁ -C ₆ -alkoxy, the unsubstituted mono- or disubstituted aryl group is phenyl or naphthyl, phenoxy, mono- or di(C ₁ -C ₆ )alkyl-substituted phenoxy, mono- or di-(C ₁ -C ₆ )alkoxy-substituted phenoxy, amino, mono(C ₁ - C ₆ )alkylamino, di(C ₁ -C ₆ )alkyl amino, phenyl amino, mono- or di (C ₁ - C ₆ )alkyl-substituted phenylamino, or mono- or di-(C ₁ - C ₆ )alkoxy-substituted phenylamino, wherein the substituents of the above-mentioned phenyl, benzyl and aryl groups are C ₁ -C ₆ -alkyl or C ₁ -C ₆ -alkoxy; b) R ₃ and R ₄ are each C ₁ -C ₆ alkyl, C ₁ -C ₆ alkoxy, chlorine or fluorine and m and n are each the integers 0, 1 or 2; c) B and B' are each selected from the group consisting of: a) the unsubstituted mono-, di- and trisubstituted aryl groups, phenyl and naphthyl; b) the unsubstituted mono- and disubstituted aromatic heterocyclic groups pyridyl, furanyl, benzofuran-2-yl, benzofuran-3-yl, thienyl, benzothien-2-yl, benzothien-3-yl, wherein the substituents of these aryl and aromatic heterocyclic groups in (c) (i) and (ii) are each selected from the group consisting of hydroxy, amino, mono(C ₁ -C ₆ )alkylamino, di(C ₁ -C ₆ )alkylamino, piperidino, morpholino, pyrryl, C ₁ -C ₆ alkyl, C ₁ -C ₆ chloroalkyl, C ₁ -C ₆ fluoroalkyl, C ₁ -C ₆ alkoxy, mono(C ₁ -C ₆ )alkoxy(C ₁ -C ₄ )alkyl, acryloxy, methacryloxy, chlorine and fluorine; (iii) the groups represented by the following graphical formulas:


wherein A is carbon or oxygen and D is oxygen or substituted nitrogen, provided that when D is substituted nitrogen, A is carbon, said nitrogen substituents being selected from the group consisting of hydrogen, C ₁ -C ₆ alkyl and C ₂ -C ₆ acyl; each R ₈ is C ₁ -C ₆ alkyl, C ₁ -C ₆ alkoxy, hydroxy, chlorine or fluorine, R ₉ and R ₁₀ are each hydrogen or C ₁ -C ₆ alkyl and p is the integer 0, 1 or 2; d) C ₁ -C ₆ alkyl, C ₁ -C ₆ chloroalkyl, C ₁ -C ₆ fluoroalkyl, C ₁ -C ₆ alkoxy(C ₁ -C ₄ )alkyl, C ₃ -C ₆ cycloalkyl, mono(C ₁ -C ₆ )alkoxy(C ₃ -C ₆ )cycloalkyl, mono(C ₁ -C ₆ )al kyl (C ₃ -C ₆ )cycloalkyl, chloro(C ₃ -C ₆ )cycloalkyl and fluorine (C ₃ -C ₆ )cycloalkyl; and (e) the group represented by the following graphic formula:


wherein X is hydrogen or C ₁ -C ₄ alkyl and Z is selected from the unsubstituted mono- and disubstituted members of the group consisting of naphthyl, phenyl, furanyl and thienyl, wherein the group substituents are C ₁ -C ₄ alkyl, C ₁ -C ₄ alkoxy, fluorine or chlorine; or (vi) B and B' together form fluoren-9-ylidene, mono- or disubstituted fluoren-9-ylidene or a member selected from the group consisting of saturated C ₃ -C ₁₂ spiromonocyclic hydrocarbon rings, saturated C ₇ -C ₁₂ spirobicyclic hydrocarbon rings and saturated C ₇ -C ₁₂ spirotricyclic hydrocarbon rings, each of said substituents of the fluoren-9-ylidene being selected from the group consisting of C ₁ -C ₄ alkyl, C ₁ -C ₄ alkoxy, fluorine and chlorine. 4. Naphthopyran according to claim 3, wherein a) R ₁ and R ₂ are each selected from the group consisting of hydrogen, hydroxy, C ₁ -C ₄ alkyl, C ₃ -C ₆ cycloalkyl, chlorine, fluorine and the group -OR ₅ , wherein R ₅ is C ₁ -C ₃ alkyl, phenyl (C ₁ - C ₂ )alkyl, mono(C ₁ -C ₃ )alkyl-substituted phenyl (C ₁ -C ₃ )alkyl, mono(C ₁ - C ₃ )alkoxy-substituted phenyl (C ₁ -C ₃ )alkyl, C ₁ -C ₃ alkoxy (C ₂ -C ₄ )alkyl, C ₁ -C ₃ chloroalkyl, C ₁ -C ₃ fluoroalkyl, the group -CH(R ₆ )X, wherein R ₆ is hydrogen or C ₁ -C ₂ alkyl and X is CN or COOR, wherein R, is hydrogen or C ₁ -C ₂ alkyl or R ₅ is the group -C(O)Y, wherein Y is hydrogen, C ₁ -C ₃ alkyl, C ₁ -C ₃ alkoxy, phenyl, naphthyl, the monosubstituted aryl groups phenyl or naphthyl, phenoxy, mono- or di(C ₁ -C ₃ )alkyl-substituted phenoxy, mono(C ₁ -C ₃ )alkylamino, phenyl amino, mono- or di(C ₁ -C ₃ )alkyl-substituted phenylamino or mono- or di(C ₁ -C ₃ )alkoxy-substituted phenylamino, each of these aryl group substituents being C ₁ -C ₃ alkyl or C ₁ -C ₃ alkoxy, b) R ₃ and R ₄ are each C ₁ -C ₃ alkyl, C ₁ -C ₃ alkoxy or fluorine, m and n are each the integers 0 or 1 c) B and B' are each selected from the group consisting of: a) phenyl, monosubstituted phenyl and disubstituted phenyl; b) the unsubstituted mono- and disubstituted aromatic heterocyclic groups pyridyl, furanyl, benzofuran-2-yl, benzofuran-3-yl, thienyl, benzothien-2-yl, benzothien-3-yl, wherein the substituents of these phenyl and aromatic heterocyclic groups in (c) (i) and (ii) are each selected from the group consisting of hydroxy, amino, mono(C ₁ -C ₃ )alkylamino, di(C ₁ -C ₃ )alkylamino, piperidino, morpholino, pyrryl, C ₁ -C ₃ alkyl, C ₁ -C ₃ chloroalkyl, C ₁ -C ₃ fluoroalkyl, C ₁ -C ₃ alkoxy, mono(C ₁ -C ₃ )alkoxy(C ₁ -C ₃ )alkyl, fluorine and chlorine; c) the groups represented by the following graphic formulas:


wherein A is carbon or oxygen, R ₈ is C ₁ -C ₃ alkyl, C ₁ -C ₃ alkoxy, R ₉ and R ₁₀ are each hydrogen or C ₁ -C ₄ alkyl and p is the integer 0 or 1; d) C ₁ -C ₄ -alkyl and (e) the group represented by the following graphic formula:


wherein X is hydrogen or C ₁ -C ₄ alkyl and Z is selected from the unsubstituted mono- and disubstituted members of the group consisting of naphthyl, phenyl, furanyl and thienyl, wherein the group substituents are C ₁ -C ₄ alkyl, C ₁ -C ₄ alkoxy, fluorine or chlorine; or (vi) B and B' together form fluoren-9-ylidene, mono- or disubstituted fluoren-9-ylidene or a member selected from the group consisting of saturated C ₃ -C ₈ spiromonocyclic hydrocarbon rings, saturated C ₇ -C ₁₀ spirobicyclic hydrocarbon rings and saturated C ₇ -C ₁₀ spirotricyclic hydrocarbon rings, each of said substituents of the fluoren-9-ylidene being selected from the group consisting of C ₁ -C ₃ alkyl, C ₁ -C ₃ alkoxy, fluorine and chlorine. 5. Naphthopyran compound according to claim 4, wherein
R ₁ and R ₂ are each hydrogen, hydroxy, C ₁ -C ₄ alkyl or the group -OR ₅ , where R ₅ is C ₁ -C ₃ alkyl; R ₃ and R ₄ are each C ₁ -C ₃ alkyl or C ₁ -C ₃ alkoxy and m and n are each the integers 0 or 1; and B and B' are each selected from the group consisting of phenyl, mono- and disubstituted phenyl, the unsubstituted mono- and disubstituted aromatic heterocyclic groups furanyl, benzofuran-2-yl, thienyl, benzothien-2-yl, where the substituents of these phenyl and aromatic heterocyclic groups are each selected from the group consisting of hydroxy, C ₁ -C ₃ alkyl, C ₁ -C ₃ alkoxy, fluorine and chlorine; and the group represented by the following graphic formula:


wherein A is carbon or oxygen, R ₈ is C ₁ -C ₃ alkyl, C ₁ -C 3 alkoxy, R ₉ and R ₁₀ are each hydrogen or C ₁ -C ₃ alkyl and p is the integer 0 or 1; or B and B' together form fluoren-9-ylidene, adamantylidene, bornylidene, norbornylidene or bicyclo(3.3.1)nonan-9-ylidene. 6. Naphthopyran compound selected from the group consisting of: a) 3-(4-Methoxyphenyl)-3-(3-methyl-4-methoxyphenyl)-13-hydroxyindeno[2,1-f]naphtho[1,2-b]pyran; b) 3,3-Di(4-methoxyphenyl)-13-hydroxy-13-methyl-indeno[2,1-f]-naphtho[1,2-b]pyran; c) 3-(4-Methoxyphenyl)-3-(2,3-dihydrobenzofur-5-yl)-13-hydroxy-13-methyl-indeno[2,1-f]naphtho[1,2-b]pyran; d) 3-(4-Methoxyphenyl)-3-(2,3-dihydrobenzofur-5-yl)-13-acetoxy-6,11-dimethoxy-13-methyl-indeno[2,1-f]naphtho[1,2-b]pyran; e) 3,3-Di(4-methoxyphenyl)-6,11-dimethyl-13-methoxy-indeno[2,1-f]naphtho[1,2-b]pyran; f) 3,3-Di(4-methoxyphenyl)-6-methyl-11-fluoro-13,13-diethoxyindeno[2,1-f]naphtho[1,2-b]pyran; g) 3,3-Di(4-methoxyphenyl)-6,11-dimethyl-13-(1-methylethyl)-13-hydroxyindeno[2,1-f]naphtho[1,2-b]pyran; h) 3-(4-Methoxyphenyl)-3-(3,4-dimethoxyphenyl)-6,11-dimethyl-13,13-dipropyl-indeno[2,1-f]naphtho[1,2-b]pyran; and i) 3,3-Di(4-methoxyphenyl)-6,11-dimethyl-13-butyl-13-hydroxyindeno[2,1-f]naphtho[1,2-b]pyran. 7. A photochromic article comprising a polymeric organic host material and a photochromic amount of a naphthopyran compound according to any one of claims 1-6. 8. A photochromic article comprising in association with one another a solid transparent polymeric organic host material and a photochromic amount of each of (a) at least one naphthopyran compound according to any one of claims 1-6 and (b) at least one other organic photochromic compound having at least one activated absorption maximum within the range between about 400 and 700 nm. 9. Photochromic article according to claim 8, wherein the organic photochromic compound (b) is selected from the group consisting of naphthopyrans, benzopyrans, phenanthropyrans, spiro-(benzindoline)naphthopyrans, spiro(indoline)benzopyrans, spiro(indoline)naphthopyrans, spiro(indoline)quinopyrans, spiro(indoline)pyrans, spiro(indoline)naphthoxazines, spiro(indoline)pyridobenzoxazines, spiro(benzindoline)pyridobenzoxazines, spiro(benzindoline)naphthoxazines, spiro(indoline)benzoxazines and mixtures of such photochromic compounds. 10. A photochromic article according to any one of claims 7-9, wherein the photochromic compound(s) is present in an amount of about 0.05 to 1.0 mg per cm ² of surface area of the organic host material into which the photochromic compound(s) is incorporated or applied. 11. A photochromic article according to any one of claims 7-10, wherein the organic host material is a polymer of an optical organic resin monomer. 12. The photochromic article of claim 11, wherein the refractive index of the polymer is from about 1.48 to about 1.75. 13. The photochromic article of claim 12, wherein the refractive index of the polymer is from about 1.495 to about 1.66. 14. A photochromic article according to any one of claims 7-13, wherein the polymeric organic host material is selected from the group consisting of poly(C ₁ -C ₁₂ alkyl methacrylates), poly(oxyalkylene dimethacrylates), poly(alkoxylated phenol methacrylates), cellulose acetate, cellulose triacetate, cellulose acetate propionate, cellulose acetate butyrate, poly(vinyl acetate), poly(vinyl alcohol), poly(vinyl chloride), poly(vinylidene chloride), polyurethanes, thermoplastic polycarbonates, polyesters, poly(ethylene terephthalate), polystyrene, poly(alpha-methylstyrene), copoly(styrenemethylmethacrylate), copoly(styrene-lacrylonitrile), polyvinyl butyral and polymers of members of the group consisting of polyol(allyl carbonate) monomers, polyfunctional acrylate monomers, diethylene glycol dimethacrylate monomers, diisopropenylbenzene monomers, ethoxylated Bisphenol A dimethacrylate monomers, ethylene glycol bismethacrylate monomers, poly(ethylene glycol) bismethacrylate monomers, ethoxylated phenol methacrylate monomers, monomers of acrylates of alkoxylated polyhydric alcohols and diallylidene pentaerythritol monomers. 15. The photochromic article of claim 14, wherein the polymeric organic host material is a solid transparent material selected from the group consisting of poly(methyl methacrylate), poly(ethylene glycol bismethacrylate), poly(ethoxylated bisphenol A dimethacrylate), thermoplastic polycarbonate, poly(vinyl acetate), polyvinyl butyral, polyurethane, polymers of members of the group consisting of diethylene glycol bis(allyl carbonate) monomers, diethylene glycol dimethacrylate monomers, ethoxylated phenol methacrylate monomers, diisopropenylbenzene monomers, and ethoxylated trimethylolpropane triacrylate monomers. 16. A photochromic article according to any one of claims 7-15, wherein the article is a lens.