RU2160277C1 - Anssa-zirconocenes functioned with respect to cyclosilane bridges, and method of preparation thereof - Google Patents

Abstract

FIELD: catalysts in chemical industry, in production of polyolefins. SUBSTANCE: described are new anssa-zirconocene with cyclosilane bridge of general formula IV:

wherein R¹ = H,CH₃,C₂H₅;R² = H, linear or branched C₁ to C₄ alkyl; aryl; A is A = BC₈H₁₄; MR₃, M is tin or silicon, R is linear or branced C₁ to C₄, alkyl; aryl; and method of preparation thereof. Method comprises synthesizing substituted indene, preparing lithium salt of indene and reacting the latter with 1,1- dichloro-2,5-dihydroxylol in diethyl ether and subsequently reacting the resulting dilithium salt of corresponding bis-indenyl ligand with silicon bridge with zirconium tetrachloride to give corresponding zirconecene and heating it in tetrahydrofuran with alkyl(aryl)derivative of boron monohydride, tin or silicon. Method makes it possible to obtain high yield of intermediate products and desired product and permit increasing content of active racemic form in metallic complex. The resulting compounds have high catalytic activity and stereoselectivity. EFFECT: improved properties of the title compounds and more efficient preparation method. 3 cl, 4 ex, 2 tbl

Description

 The invention relates to new bridge zirconocenes (CC), namely to ansa-zirconocenes with a cyclosilane bridge, functionalized directly along the bridge, which can be used as catalysts in the chemical industry in the production of polyolefins (PO).

 Bridged (ansa-) CCs, especially CCs with a silicon bridge, are among the most active homogeneous metallocene catalysts (MCCs) for the polymerization of olefins, the discovery of which revolutionized PO synthesis due to their extremely high catalytic activity and stereoselectivity. MCC are used in conjunction with polymethylaluminoxane (MAO) as a cocatalyst (Sinclair K., Wilson R. Chemistry and Jndustry, 1994, N 7, p. 857).

Currently, a large number of Ansa-metallocenes and zirconocenes are known. Closest to the proposed ansa-zirconocenes and the method for their preparation are sterically hindered CCs with a silicon bridge and the method for their preparation described in Spaleck W. et al. Organometallics, 1994, 13, p. 954 - a prototype, which are bis-indenyl derivatives of ansa-zirconocenes C ₂ - symmetry with a silicon bridge of the formula I, II or III.

Ia R¹=R²=R³=Me;
Ib R¹=R²=Me, R³=Ph;
Ic R¹=H, R²=R³=Me;
IIa R=Me;
IIb R=H.

Ia R ¹ = R ² = R ³ = Me;
Ib R ¹ = R ² = Me, R ³ = Ph;
Ic R ¹ = H, R ² = R ³ = Me;
IIa R = Me;
IIb R = H.

 The preparation of known compounds I-III is shown in Example 1 a-c of Scheme 1.

The first stage of synthesis is the preparation of indenyl ligands (4). The starting compound is 2-phenylbenzyl bromide (1), which is condensed with malonic or methyl malonic ether in the presence of sodium ethylate. Subsequent reactions of saponification of the ether (in the presence of aqueous alkali) and decarboxylation by heating at 130 ^° C give the corresponding acid (2) in good yield (85% of theory per crude (2)). The reaction of acid (2) with thionyl chloride gives its acid chloride, which is cyclized to indanone (3) in the presence of AlCl ₃ as a Friedel-Crafts catalyst. The yield of indanones was satisfactory except for naphthylindanone, an intermediate product in the synthesis of compound III, since the higher reactivity of the naphthyl derivative led to side reactions, and the yield of naphthylindanone was only 13%. Indanone (3) is then reduced with sodium borohydride in a mixture of tetrahydrofuran (THF) and methanol at 0 ^° C, boiled in the presence of p-toluenesulfonic acid and inden (4) is isolated by preparative TLC (thin layer chromatography) on silica gel in good yield.

The next stage is the preparation of bisindenyl ligands with a silicon bridge (5). Indene (4) was dissolved in a mixture of dry toluene and THF in an argon atmosphere and a solution of n-butyllithium in hexane was added at room temperature. Heated to 80 ^o C, kept at 80 ^o C for 1 hour and cooled to 0 ^o C, dimethylsilane dichloride (a, c) or methylphenylsilane (b) was added. Heated for 1 hour at 80 ^o C and treated with water. Compound (5) is isolated from the organic layer by TLC. Yield (5a) 70%, (5b) 44%, (5c) 62%.

The final stage is to obtain zirconocene 1 a-s. To a solution (5) in dry toluene in an argon atmosphere, a solution of n-BuLi in hexane is added at room temperature. It is refluxed for 3 hours, cooled to -25 ^° C and zirconium tetrachloride is added. Leave for 2 hours. The zirconium complex is filtered, which is a mixture of racemic (active) and meso (inactive) forms (rat: meso = 1: 1). Recrystallized from methylene chloride. Yield 1 a 33%, I b 10%, 1 s 15%
The work selected for the prototype analyzed earlier results on the influence of the structure of metallocenes on their behavior in the polymerization of olefins, and in order to study the effect of aromatic substituents in the indenyl nucleus of bridge CC, compounds I-III were synthesized, which were tested with MAO as cocatalyst (Al: Zr = 15000: 1) in the polymerization of propylene and ethylene. The polymerization of propylene in the prototype work was carried out in a liquid monomer at 70 ^o C in a thermostatic steel reactor. MAO was used as a 10% solution in toluene, and CC was dissolved in the same MAO solution. The results showed (see table 1) that the introduction of a volume aromatic substituent in the 4-position of the indenyl nucleus significantly improves all indicators of the polymerization process compared with unsubstituted (2a ^* ) or 4-alkyl substituted (4a ^* ) CCs described previously in other works.

When carrying out the polymerization of ethylene (in solution), the highest catalytic activity, as in the reaction with propylene, was shown by compounds Ia and III, and they also showed the highest M _W [2].

 It should be emphasized that the unprecedentedly high rates of the polymerization process obtained using compounds Ia and III, in comparison with other bridge zirconocenes, make it possible to consider compounds Ia and III as the best known today as catalysts for the polymerization of olefins together with MAO, and the fact of the discovery of such an effect aromatic substituent in the 4th position of the indenyl ring a major contribution to the chemistry of MCC.

 However, CC I-III, like other known MCC, are synthetically difficult to access. Thus, compound III, exhibiting the highest catalytic activity, is the most inaccessible of the CC I-III due to the low yields of intermediate products in the synthesis. In addition, the known CC I-III are characterized by a high content of the meso form inactive in the polymerization reaction (1: 1 ratio of the racem and meso isomers), from which it is desirable to release the metal complex, which is very difficult and often impossible.

 It is necessary to note one more drawback of the known MCCs - all known modifications of the structure of metallocenes are carried out at the very early stages of their synthesis, which greatly inhibits studies of catalytic activity, since it is impossible to foresee either the yield at intermediate stages or the very possibility of obtaining both a bridging ligand and the final the target product - the metal complex, and whether the metallocenes obtained will be soluble in organic solvents (toluene) in order to be promising for the preparation of homogeneous kat izatorov.

 The objective of the invention is the creation of new ansa-CC, with high activity and stereoselectivity as a catalyst for the polymerization of olefins and having a fundamentally new structure, namely, functionalized directly on a silicon bridge, which will allow them to be used as an object of study when studying the influence of functional substituents in the bridge, that is, in the immediate vicinity of the catalytic center, as well as the development of a method for their production with a sufficiently high yield intermediate and final products with improved methods for the isolation of intermediate products and with an increased content of the active racemic form in the zirconium complex.

R¹ = H, CH₃, С₂H₅;
R² = H, алкил от С₁ до С₄, нормальный или разветвленный; арил;
А = BC₈H₁₄; MR₃, где М - олово или кремний, R = алкил от C₁ до C₄, нормальный или разветвленный; арил.The solution to this problem is achieved:
- the proposed new ansa-zirconocenes functionalized on the cyclosilane bridge of formula IV:

R ¹ = H, CH ₃ , C ₂ H ₅ ;
R ² = H, alkyl from C ₁ to C ₄ , straight or branched; aryl;
A = BC ₈ H ₁₄ ; MR ₃ , where M is tin or silicon, R = C ₁ to C ₄ alkyl, straight or branched; aryl.

 - and a method for their preparation, in which the lithium salt of indene is reacted with 1,1 - dichloro-2,5-dihydrosilol in diethyl ether, followed by reaction of the obtained dilithium salt of the corresponding bisindenyl ligand with a silicon bridge with zirconium tetrachloride to obtain the corresponding zirconocene and heating it in tetrahydrofuran with an alkyl (aryl) derivative of boron, tin or silicon monohydride. Zirconocene is heated in tetrahydrofuran with alkyl (aryl) derivatives of (mono) boron, tin or silicon hydride.

 The preparation of the dilithium salt of a bis-indenyl product with a silicon bridge can be carried out in the form of a crystalline adduct with diethyl ether, which is then reacted with zirconium tetrachloride.

 When developing the proposed invention, new CCs with an unsaturated cyclosilane bridge (described in a separate application filed simultaneously with this one) were originally created, which made it possible to obtain ansa-CCs functionalized along the bridge.

 The introduction of functional substituents, especially bulky ones, into the CC bridge, i.e., in the immediate vicinity of the catalytic center, is of great interest for the chemistry of MCC, since it creates completely new spatial effects in the metal complex, which inevitably should affect the stereoselective properties of the catalyst.

The synthesis of the proposed CC IV is described in the examples and is shown in Scheme 2. The obtained compounds IV (and intermediate products) are characterized by elemental analysis data and NMR spectra ( ¹ H, ¹³ C).

 Compounds IV together with MAO as a cocatalyst were tested in the polymerization of propylene. The polymerization process was carried out according to the method similar to that described in the prototype work. The results are presented in table 2.

 Examples.

I. Synthesis of substituted indene (4 ² ).

Synthesis of propanedicarboxylic acid diethyl ester CH ₃ CH ₂ CH (COOEt) ₂ (ethyl malonic ester).

 To a sodium ethylate solution prepared from 16.2 g (0.705 g-atom) of sodium and 350 ml of abs. ethanol was added with stirring 53 ml (55.92 g, 0.349 mol) of malonic acid diethyl ether. To the solution thus prepared, while cooling in an ice bath, 53 ml (77.38 g, 0.710 mol) of ethyl bromide were slowly added, the mixture was allowed to warm to room temperature and was stirred for another 30 minutes. Ethyl alcohol was distilled off, water was added until the precipitate was completely dissolved, the resulting mixture was extracted with ether, the combined ether extracts were dried with sodium sulfate, the solvent was distilled off, and the remaining oil was distilled to give 52.33 g (80%) of the desired product.

 Methyl malonic ester was prepared in a similar manner (sodium methylate was used instead of sodium ethylate).

Synthesis of 2- (hydroxymethyl) diphenyl 2-PhC ₆ H ₄ CH ₂ OH (2-phenylbenzyl alcohol).

To a suspension of 5.7 g (150.0 mmol) of lithium aluminum hydride in 50 ml of boiling tetrahydrofuran, a solution of 12.5 g (63.1 mmol) of 2-phenylbenzoic acid in 100 ml of absolute tetrahydrofuran was added with stirring over 4 hours, the reaction mixture was boiled for another 3 hours and left overnight . The reaction mixture was carefully treated with vigorous cooling with ice water until the evolution of hydrogen was complete and then with sulfuric acid (1: 1) until the precipitate was completely dissolved. The solution thus obtained was extracted three times with ether, the combined ether extracts were dried with sodium sulfate, the solvent was distilled off, and the remaining oil was cooled before crystallization began. Chromatographically pure product. Mp 29 ^o C. Yield 9.54 g (82%).

 In a similar manner, 2-alkyl and 2-naphthylbenzyl alcohol are obtained (instead of-2-phenylbenzoic acid, 2-alkyl or 2-naphthylbenzoic acid is used).

Synthesis of 2- (bromomethyl) diphenyl 2-PhC ₆ H ₄ CH ₂ Br (2-phenylbenzyl bromide) (1 ² ).

A mixture of 3.20 g (17.37 mmol) of 2- (hydroxymethyl) diphenyl, 5 ml conc. HBg and 1.2 ml conc. H ₂ SO ₄ was refluxed for 6 hours, cooled and poured into 20 ml of ice water. The organic phase (lower layer) was separated, washed with saturated sodium carbonate solution; the aqueous phase was neutralized with sodium carbonate and extracted three times with ether. The combined organic phase was dried with sodium sulfate, the solvent was distilled off, and the remaining oil was distilled under reduced pressure, collecting a fraction of 160-165 ^° C / 7 mm Hg. Art., which gave 3.64 g of pure product. Yield 85%. Caution! Strong lacrimator!
Similarly, 2-alkyl and 2-naphthylbenzyl bromide were obtained.

Synthesis of 2- (2-diphenylmethyl) butanoic acid (Et) (2-PhC ₆ H ₄ CH ₂ ) CHCOOH (2 ² ).

To a sodium ethylate solution prepared from 1.40 g (60.9 mg atom) of sodium and 47 ml of abs. ethanol was added at room temperature with stirring a solution of 11.70 g (62.2 mmol) of ethyl malonic acid diethyl ether in 15 ml of abs. ethanol. To the solution thus prepared, at a slight boil, a solution of 15.60 g (63.1 mmol) of 2- (bromomethyl) diphenyl in 20 ml of abs. Was added dropwise. ethanol, the reaction mixture was boiled for another 3 hours. The reaction mixture was cooled, treated with cooling with a solution of 9 g of KOH in 25 ml of water, again boiled for 4 hours and cooled. The solvents were distilled off in a vacuum of a water-jet pump and the residue was acidified with concentrated hydrochloric acid to pH 1. The precipitated white precipitate was filtered off and heated in a Wood alloy bath for 1 hour at 130 ^° C. A pale yellow oil was used without further purification.

Synthesis of 2- (2-diphenylmethyl) butanoic acid chloride (Et) (2-PhC ₆ H ₄ CH ₂ ) CHC (O) Cl.

 To 7.20 g (28.2 mmol) of 2- (2-diphenylmethyl) butanoic acid was added 20 ml of freshly distilled thionyl chloride and the resulting solution was refluxed for 1 hour. Excess thionyl chloride was distilled off; to complete removal of thionyl chloride, abs. 30 ml of toluene and distilled off in vacuum. The residue was dissolved in 50 ml of abs. toluene and was used without further processing.

Synthesis of 4-phenyl-2-ethylindanone-1 2-Et-4-Ph-C ₉ H ₆ O (3 ² ).

A solution of 2- (2-diphenylmethyl) butanoic acid chloride in 50 ml of abs. toluene was added over 1 hour with stirring and cooling to 10 ^° C. to a suspension of 5.70 g (42.7 mmol) of anhydrous aluminum chloride in 50 ml of absolute toluene. The mixture was stirred at 80 ^o C for 1 hour, poured onto 300 g of crushed ice, acidified with conc. HCl to pH 1, the organic phase was separated, and the aqueous was extracted three times with ether. The combined organic phases were washed with water, a soda solution and dried over sodium sulfate and the solvents removed in vacuo. The crude product was purified by preparative column chromatography (silica gel, petroleum ether - ether 2: 1). Light yellow crystals. Yield 4.65 g (70% based on 2- (2-diphenylmethyl) butanoic acid). 4-phenyl-2-methylindanone, 4-phenylindanone, 4-alkyl-2-alkylindanone and 4-naphthyl-2-R ¹ -indanone (R ¹ = H, CH ₃ , C ₂ H ₅ ) were similarly prepared.

Synthesis of 4-phenyl-2-ethylindene 2-Et-4-PhlndH (4 ² ).

To a solution of 7.10 g (30.0 mmol) of 4-phenyl-2-ethylindanone-1 in a mixture of 30 ml of abs. tetrahydrofuran and 15 ml abs. Under stirring and cooling to 0 ^° C, methanol was added slowly in small portions of 1.70 g (44.9 mmol) of ground sodium borohydride. The mixture was stirred for another 16 hours, poured onto 100 g of crushed ice, acidified with conc. HCl to pH 1, was extracted three times with ether. The organic extracts were washed with saturated sodium chloride solution and dried with magnesium sulfate. The solvents were distilled off in vacuo and the remaining oil was dissolved in 100 ml of dry toluene containing 0.3 g of n-toluenesulfonic acid monohydrate and boiled for 2 hours. The cooled solution was washed with saturated aqueous sodium bicarbonate, dried with sodium sulfate, the solvent was removed in vacuo, and the residue was purified by preparative silica gel column chromatography using a 9: 1 petroleum ether-dichloromethane mixture as eluent. Colorless oil. 3.70 g (56% based on 4-phenyl-2-ethylindanone-1).

¹ H NMR (400 MHz, CDCl ₃ , 25 ^° C.) δ ppm: 7.63-7.17 (m, 8H, aromatic protons of indene and phenyl groups); 6.59 (i.e., ⁴ J = 1.6 Hz, 1H, indene olefin proton); 3.43 (s, 2H, allylic indene protons); 2.52 (br.s., ³ J = 7.6 Hz, 2H, CH2 - protons of the ethyl group); 1.24 (i.e., ³ J = 7.6 Hz, 3H, CH3-protons of the ethyl group);
¹³ C { ¹ H} (100 MHz, CDCl ₃ , 25) δ ppm: 152.72, 146.24, 141.37, 140.56, 137.46 (quaternary aromatic and olefinic carbons of indene and phenyl group); 128.44, 128.35, 126.98, 125.22, 125.19, 124.28, 119.09 (tertiary aromatic and olefin carbons of indene and phenyl group); 41.00 (allyl carbon of indene); 24.26 (methylene carbon ethyl group); 13.28 (methyl carbon of the ethyl group).

Other substituted indenes (4 ² ) with R ¹ and R ² indicated in Scheme 2 were similarly prepared.

 II. Synthesis of CC with unsaturated cyclosilane bridge.

 Synthesis of 4-phenyl-2-ethylindenyl lithium 2-Et-4-PhlndLi.

 The synthesis was carried out in vacuum-soldered apparatus such as Schlenk vessels.

To a solution of 11.00 g (49.93 mmol) of 4-phenyl-2-ethylindene (4 ² ) in 70 ml of diethyl ether was added, while cooling to -20 ^° C and vigorous stirring, 23.8 ml (49.98 mmol) of a 2.1 M solution of n-butyllithium in light petroleum ether, allowed the mixture to warm to room temperature and left overnight. About half of the total solvent volume was distilled off, the yellow volume precipitate was separated by filtration from the intense red mother liquor, washed three times with pentane on the filter (70 ml each), dried in high vacuum, and the resulting snow-white solid was dissolved in 100 ml of diethyl ether. The clear yellow solution was separated from the fine precipitate by double decantation, titrated and used as a 0.35 M solution. Received 105 ml of a 0.35 M solution, yield 73.5% of theory. Similarly, lithium salts with other substituted indenes were obtained.

Synthesis of 1,1 '- (butene-2-diyl-1,4) silylidenebis (4-phenyl-2-ethylindene) (1,4-CH ₂ CH = CHCH ₂ ) Si (2-Et-4-PhlndH) ₂ (5 ² ).

To a solution of 1.14 g (7.44 mmol) of 1,1-dichloro-2,5-dihydrosilol in 30 ml of diethyl ether, while cooling to -30 - -40 ^o C and vigorous stirring for 30 minutes was added 42.5 ml of a 0.35 M ether solution (4 -phenyl-2-ethylindenyl lithium) (14.86 mmol), allowed the mixture to gradually warm to room temperature and left overnight. The solution was filtered from the precipitated lithium chloride, the solvent was distilled off, 50 ml of pentane were added, and after repeated filtering and distillation of the solvent, the remaining slightly yellow glassy oil was dried under high vacuum. The output is almost quantitative. The bidentate ligand (5 ² ) was completely purified in the form of its dilithium derivative.

 Similarly, 1,1-dichloro-2,5-dihydrosilol was reacted with the Li salts of other substituted indenes.

1,1 '- (butene-2-diyl-1,4) silylidenebis (4-phenyl-2-ethylindenyl) dilithium adduct with diethyl ether (1,4-CH ₂ CH = CHCH ₂ ) Si (2-Et-4 -Phlnd) ₂ Li ₂ • Et ₂ O (add). To a solution of the ligand (5 ² ) obtained in the previous step in a mixture of 10 ml of diethyl ether and 40 ml of pentane was added 6.54 ml of a 2.16 M solution of n-butyllithium in hexane (14.12 mmol) while cooling to -20 ^° C and the mixture was allowed to warm to room temperature. The initially separated yellow oil gradually crystallized. The precipitate was filtered off, washed three times on the filter with the same solvent mixture, and the resulting snow-white powdery substance was dried under high vacuum. Obtained 3.19 g (5.26 mmol) of dilithium salt (add). Yield 70.7% based on the initially taken 4-phenyl-2-ethylindenyl lithium.

NMR (THF-d ₈ , 30 ^o C) d ppm ¹ H: 1.31 (t, CH ₂ CH ₃ ); 2.18 (s, CH ₂ Si); 3.04 (q, CH ₂ CH ₃ ); 6.03 (s, CH = CH); 6.32 (s, H ³ ); 6.52 (m, H ⁵ , H ⁶ ); 7.12 (t, para-H); 7.30 (t, meta-H); 7.69 (m, H ⁷ ); 7.79 (d, ortho-H).

¹³ C: 17.58 (CH ₂ CH ₃ ); 22.63 (CH ₂ Si); 25.89 (CH ₂ CH ₃ ); 95.97 (C ³ ); 96.54 (C ¹ ); 113.82, 114.14, 119.86 (C ⁵ , C ⁶ , C ⁷ ); 125.02 (para-C); 128.22 (meta-C); 129.24 (ortho-C); 132.60 (CH = CH); 130.34, 131.16, 137.77, 145.22, 147.36 (C ^3a , C ^7a , ² , C ⁴ , ipso-C).

 Similarly, diethyl ether adducts of dilithium salts of other bidentate ligands with unsaturated cyclosilane bridge were obtained.

Synthesis of {η ⁵ , η ⁵ ′ - [1,1 '- (Butene-2-diyl-1,4) silylidenebis (4-phenyl-2-ethylindenyl)]} dichlorocirconium (1,4-CH ₂ CH = CHCH ₂ ) Si (2-Et-4-Phlnd) ₂ ZrCl ₂ , mixture of rac and meso forms (2: 1).

A suspension of 3.19 g (5.26 mmol) of dilithium salt ether (add) and 1.24 g (5.26 mmol) of ZrCl ₄ in 100 ml of toluene was stirred overnight at room temperature, another 500 ml of toluene was added, the orange mother liquor was separated from the very finely divided precipitate by decantation ( 3 weeks), toluene was distilled off and the residue was recrystallized from the minimum volume of methylene chloride, which gave 2.40 g (3.53 mmol) of the target complex, which is a mixture of the rac and meso forms in a 2: 1 ratio. Yield 67.1%.

NMR ¹ H (CD ₂ Cl ₂ , 30 ^° C) d ppm: 1.11 (t, CH ₂ CH ₃ , rac); 1.21 (t, CH ₂ CH ₃ , meso); 2.41 (m), 2.74 (m) (CH ₂ CH ₃ , rac); 2.76 (m, CH ₂ CH ₃ , meso); 2.55 (broad s), 2.89 (broad s) (CH ₂ Si, meso); 2.61 (AB system), 2.78 (AB system, ² J (AB) = 18 Hz) (CH ₂ Si, rac); 6.33 (s, HC = CH, rac); 6.33 (m), 6.36 (m) (HC = CH, meso); 6.86 (s, H ³ , meso); 6.97 (s, H ³ , rac); 6.93 (m), 7.10 - 7.65 (m) (H ⁵ , H ⁶ , H ⁷ , Ph).

C ₃₈ H ₃₄ Cl ₂ Si ₁ Zr ₁ , M = 680.96. Found: Cl = 9.80% ,. Calculated: Cl = 10.43%.

 Similarly, CCs with unsaturated cyclosilane bridge with other substituted bisindenyl ligands were obtained.

Synthesis of {η ⁵ , η ⁵ ′ - [1,1 '- (Butene-2-diyl-1,4) silylidenebisindenyl]} dichloro zirconium (1,4-CH ₂ CH = CHCH ₂ ) Silnd ₂ ZrCl ₂ , a mixture of rac- and meso forms (1: 1).

 Synthesis of Inddenyllithium IndLi.

To a solution of 11.62 g (100.00 mmol) of Aldrich manufactured indene in 50 ml of diethyl ether was added, while cooling to -20 ^° C and vigorous stirring, 53.2 ml (100.01 mmol) of a 1.88 M solution of n-butyllithium in light petroleum ether, and the mixture was allowed to warm to room temperature and left overnight. About two thirds of the total solvent volume was distilled off, the white crystalline precipitate formed was separated by filtration from the intense red mother liquor, washed three times with pentane on the filter (70 ml each), and dried in high vacuum. Snow-white crystalline substance. Yield 10.90 g (89.27 mmol, 89.3% of theory).

Synthesis of 1,1 '- (butene-2-diyl-1,4) silylidenebisindene (1,4-CH ₂ CH = CHCH ₂ ) Si (IndH) ₂ (5 ² ), R ¹ = R ² = H.

A solution of 4.58 g (37.51 mmol) of indenyl lithium was added to a solution of 2.86 g (37.51 mmol) of 1,1-dichloro-2,5-dihydrosilol in 30 ml of diethyl ether while cooling to -30 - -40 ^° C and vigorous stirring for 30 minutes. in diethyl ether, allowed the mixture to gradually warm to room temperature and left overnight. The solution was filtered from the precipitated lithium chloride, the solvent was distilled off, 50 ml of pentane were added, and after repeated filtering and distillation of the solvent, the remaining slightly yellowish oil was dried under high vacuum. The output is almost quantitative. Complete purification of the ligand (5 ² ) (R ¹ = R ² = N) was carried out in the form of its dilithium derivative.

Synthesis of [1,1 '- (butene-2-diyl-1,4) silylidene bisindenyl] dilithium (adduct with diethyl ether) (1,4-CH ₂ CH = CHCH ₂ ) Silnd ₂ Li ₂ • Et ₂ O (add, R ¹ = R ² = H).

To a solution of 5.14 g (16.45 mmol) of the ligand obtained in the previous step (5 ² ) in 50 ml of diethyl ether while cooling to -20 ^° C and vigorous stirring was added 15.2 ml of a 2.16 M solution of n-butyllithium in hexane (16.45 mmol), warm to room temperature and left overnight. The precipitated white precipitate was filtered off, washed three times on the filter with the same solvent mixture, and the obtained snow-white powdery substance was dried in high vacuum. Received 4.91 g (12.32 mmol) of dilithium salt (add). Yield 74.9% calculated on the initial taken indenyl lithium.

NMR (THF-d ₈ , 30 ^o C) d ppm ¹ H: 1.91 (s, CH ₂ Si); 6.01 (s, CH = CH); 6.04 (d, ³ J (H ² -H ³ ) = 3.2 Hz, H ² ); 6.47 (m, H ⁵ , H ⁶ ); 6.88 (d, H ³ ); 7.32 (m, H ⁷ ); 7.64 (m, H ⁴ ).

¹³ C: 20.50 (CH ₂ Si); 95.14 (C ³ ); 98.26 (C ¹ ); 114.33, 114.63, 119.40, 121.67, 125.99 (C ² , C ⁴ , C ⁵ , C ⁶ , C ⁷ ); 132.78 (CH = CH); 133.89, 136.28 (C ^3a , C ^7a ).

Synthesis of {η ⁵ , η ⁵ ′ - [1,1 '- (Butene-2-diyl-1,4) silylidene bisindenyl]} dichloro-zirconium (1,4-CH ₂ CH = CHCH ₂ ) SiInd ₂ ZrCl ₂ , a mixture of rac- and meso forms (1: 1).

A suspension of 1.34 g (3.36 mmol) of dilithium salt ether (add) and 0.78 g (3.36 mmol) of ZrCl ₄ in 70 ml of toluene was stirred during the day, the dry residue was repeatedly extracted with toluene, the toluene extract was concentrated, the crystalline yellow precipitate was filtered off from the mother liquor, washed with toluene , pentane and dried in high vacuum, which gave 1.02 g (2.17 mmol) of the metal complex, which is a mixture of the rac and meso forms in a 1: 1 ratio. Yield 64.5%.

NMR (CD ₂ Cl ₂ , 30 ^o C) d ppm: ¹ H (CD ₂ Cl ₂ , 30 ^o C) 2.29 (broad s), 2.64 (broad s) (CH ₂ Si, meso) 2.37 (AB system), 2.56 (AB system, ² J (AB) = 17 Hz) (CH ₂ Si, rac); 6.11 (d, ³ J (H ² -H ³ ) = 3.5 Hz, H ² , rac); 6.17 (d, ³ J (H ² -H ³ ) = 3.5 Hz, H ² , meso); 6.29 (s, CH = CH, rac); 6.29 (m), 6.30 (m) (CH = CH, meso); 6.90 (d, H ³ , rac); 6.95 (d, H ³ , meso); 6.93 (m), 7.22 (m) (H ⁵ , H ⁶ , meso); 7.10 (m), 7.39 (m) (H ⁵ , H ⁶ rats); 7.51 (m), 7.60 (m) (H ⁴ , H ⁷ , rac, meso).

¹³ C: 16.45, 16.86 (CH ₂ Si, meso); 16.99 (CH ₂ Si, rac); 87.94 (C ¹ , rac); 89.08 (C ¹ , meso); 117.95, 118.14, 124.38, 126.34, 127.18, 128.00 (C ² , C ³ , C ⁴ , C ⁵ , C ⁶ , C ⁷ , rat); 119.62, 119.85, 125.75, 126.06, 126.34, 127.54 (C ² , C ³ , C ⁴ , C ⁵ , C ⁶ , C ⁷ , meso); 130.65, 130.88 (CH = CH, meso); 130.70 (CH = CH, rac); 125.89, 133.79 (C ^3a , C ^7a , rac); 128.13, 134.93 (C ^3a , C ^7a , meso). C ₂₂ H ₁₈ Cl ₂ Si ₁ Zr ₁ , M = 472.67. Found: Cl = 14.38%. Calculated: Cl = 15.02%.

 III. Synthesis of functionalized on a silicon bridge CC of the formula IV.

Synthesis of boron ansa-zirconocene with unsubstituted bisindenyl ligands IVa (η ⁵ : η ⁵ -1.1 '(3- (9-borabicyclononanil-9) silolanediyl-1,1) bisindenyl] dichlorocirconium).

A solution of 125 mg (264.5 mmol) of ansa-zirconocene -1,1 '[(But-2-diyl-1,4) silylidene] -bisindenyl-dichloro-zirconium (a mixture of the rac and meso forms) and 9-borabicyclo [3 , 3, 1] nonane (32 mg, 132.3 mmol) in THF was mixed at room temperature, heated at 70 - 80 ^o C in a sealed vessel, cooled, the solvent was removed, and the residue was dried in vacuo. Received a crystalline substance of yellow-orange color. The output is quantitative. C ₃₀ H ₃₃ B ₁ Cl ₂ Si ₁ Zr ₁ . M = 594.69.

 Found: Zr = 15.88; Cl = 11.38. Calculated: Zr = 15.34; Cl = 11.92.

Synthesis of stannylated ansa-zirconocene with unsubstituted bisindenyl ligands IV b ([η ⁵ : η ⁵ -1.1 '(3- (trimethylstanyl) silolanediyl-1,1) bisindenyl] dichlorocirconium).

A mixture of 125 mg (264.5 mmol) of ansa-zirconocene 7 (a mixture of rac and meso forms) and 43 mg (264.5 mmol) of trimethylstannan in 30 ml of THF was heated at 70 - 80 ^° C in a sealed vessel for 5 hours . The mixture was cooled and the solvent was removed in vacuo. The resulting yellow-orange oil was washed with pentane (2 times 30 ml). The resulting dry residue was dissolved in ether, the solution was filtered and the ether removed. Received 155 mg (92% of theory.) Complex IVb. C ₂₅ H ₂₈ Cl ₂ Si ₁ Sn ₁ Zr ₁ , M = 637.49.

 Found: Zr = 14.90; Cl = 10.85. Calculated: Zr = 14.31; Cl = 11.12.

Synthesis of boron ansa-zirconocene with substituted bisindenyl ligands IVc ([η ⁵ : η ⁵ -1.1 '(3- (9-borabicyclononanil-9) silolanediyl-1,1) bis-4-phenyl-2-ethylindenyl] dichlorocirconium) .

The synthesis of complex IVc was carried out by the method of synthesis of zirconocene IVa. The main difference and the main difficulty is that the product is formed in the form of poorly crystallizing oil. The solid product is obtained by repeatedly washing the products with pentane at -20 (-30) ^o C. IVc yield 85% (of theoretical). C ₄₆ H ₄₉ B ₁ Cl ₂ Si ₁ Zr ₁ , M = 802.98.

 Found: Zr = 11.80; Cl = 8.25. Calculated: Zr = 11.36; Cl = 8.83.

 IV. Polymerization of propylene.

 Methodology

A pre-evacuated 0.25 L reactor is filled with liquid propylene, 2-3 ml of a 10% toluene MAO solution and zirconocene pre-dissolved in a 10% MAO toluene solution in an amount of 0.1-110 ^-6 mol are added. Heated to 50-70 ^o C and conduct polymerization for 20-30 minutes.

The output of the IPP is determined by weighing. The molecular weight characteristics of polypropylene were obtained by gel permeation chromatography on a Waters 150-C high-temperature gel chromatograph. The stereoregularity parameters are determined from the ratio of the absorption bands in the IR spectra of D ₉₉₈ / D ₉₇₃ . The melting points ( _Tm ) of the obtained polymers were determined by differential scanning calorimetry on a DSC-910 calorimeter (DuPont Instrument). The results of the experiments and the properties of the obtained polymers are shown in table 2.

 The data presented show that the proposed CCs with a functionalized cyclosilane bridge have high catalytic activity and stereoselectivity.

 The method for their preparation is characterized by high yields of intermediate and target products, an improved procedure for the isolation of dilithium derivatives of bridge ligands and allows to double the content of the active racemic form in the metal complex.

Claims (3)

1. Ansa-zirconocenes functionalized on a cyclosilane bridge, of general formula IV

R ¹ = H, CH ₃ , C ₂ H ₅ ;
R ² = H, C ₁ to C ₄ alkyl, straight or branched, aryl;
A = BC ₈ H ₁₄ , MR ₃ , where M is tin or silicon, R is C ₁ to C ₄ alkyl, straight or branched, aryl.  2. The method of producing ansa-zirconocenes functionalized by the cyclosilane bridge of formula IV according to claim 1, characterized in that the lithium salt of indene is reacted with 1,1-dichloro-2,5-dihydrosilol in diethyl ether, followed by the interaction of the obtained dilithium salt of the corresponding bisindenyl ligand with a silicon bridge with zirconium tetrachloride to obtain the corresponding zirconocene and heating it in tetrahydrofuran with an alkyl (aryl) derivative of boron, tin or silicon monohydride.  3. The method according to claim 2, characterized in that the preparation of the dilithium salt of the bisindenyl ligand with a silicon bridge is carried out in the form of a crystalline adduct with diethyl ether, which is then reacted with zirconium tetrachloride.

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