CN103242357B - A kind of synthetic method of polysubstituted Silole derivative - Google Patents

Abstract

The invention provides a method for synthesizing polysubstituted silacyclopentadiene derivatives. Using 2-(trimethylsilyl)aryl trifluoromethanesulfonate derivatives to react with alkynes, under the action of a catalyst, to prepare multi-substituted silacyclopentadiene derivatives, the yield is high, and the synthesis method is scientific and reasonable , and the method has easy-to-obtain raw materials, wide application range, high separation yield, simple experimental equipment and operation, and is convenient for further development and application.

Description

A kind of synthetic method of polysubstituted silacyclopentadiene derivative

technical field

The invention belongs to the field of organic synthesis and relates to a general synthesis method of silacyclopentadiene derivatives with various substituents.

Background technique

Multi-substituted silacyclopentadiene (silole) derivatives have low reduction potential and lowest unoccupied orbital (LUMO), strong electron mobility and electron affinity, and strong ability to accept electrons. This unique electronic structure makes it have great application prospects in the field of optoelectronic materials, such as electroluminescent (EL) materials, light-emitting diode (LED) organic semiconductor materials, electron transport materials, nonlinear optical materials, etc. The currently reported synthetic methods mostly use equivalent metal reagents, the reaction is relatively harsh, and the tolerance of functional groups is low, so that it is impossible to effectively realize multiple substituent groups, and also limits the diversity of substituent groups.

Contents of the invention

The object of the present invention is to provide a general method for the synthesis of silacyclopentadiene derivatives with various substituents. Technical scheme of the present invention is as follows:

A kind of synthesis method of multi-substituted silacyclopentadiene derivatives is to combine 2-(trimethylsilyl) aryl trifluoromethanesulfonate derivatives shown in formula (I) with formula (II) The alkyne reacts with the catalyst represented by formula (III) in a non-polar solvent, and the reaction temperature is between 90°C and the boiling point of the non-polar solvent;

in:

R ¹ is a substituent at any position on the benzene ring, which can be a single substitution, multiple substitution or a ring structure, which means:

Alkyl groups with 1-12 or more carbon atoms, such as: methyl, ethyl, propyl, isopropyl, butyl, isobutyl, ..., undecyl, dodecyl, tridecyl, ..., octadecyl, etc., more preferably C1-6 alkyl, more preferably C1-4 alkyl;

Aryl groups with 6-12 carbon atoms, such as phenyl, biphenyl, naphthyl, etc.;

Or a heterocyclic aryl group with 2-5 carbon atoms, such as thienyl, thiazolyl, pyridyl, etc.

The above-mentioned groups may be substituted by substituents, and the substituents may be common C1-4 alkyl or alkoxy groups, hydrogen atoms, halogen atoms (F, Cl, Br), cyano groups, nitro groups and the like.

R ² and R ³ may be the same or different, and each independently represents:

Silyl groups with 3-12 carbon atoms, such as trimethylsilyl, triethylsilyl, tripropylsilyl, etc.;

Aryl groups with 6-12 carbon atoms, such as phenyl, biphenyl, naphthyl, etc.;

Or a heterocyclic aryl group with 2-5 carbon atoms, such as thienyl, thiazolyl, pyridyl, etc.

The above-mentioned groups may be substituted by substituents, and the substituents may be common C1-4 alkyl or alkoxy groups, hydrogen atoms, halogen atoms (F, Cl, Br), cyano groups, nitro groups and the like.

The catalyst used in the present invention is a mixture of allyl palladium chloride or its dimer, tri-tert-butyl phosphine, lithium ethylate and potassium bromide or tetramethylammonium bromide. All reagents can be used as commercial reagents without special treatment.

The non-polar solvent used in the present invention may be toluene, xylene or 1,4-dioxane or a mixture thereof. The non-polar solvent can be a commercially available reagent, which can be dried with molecular sieves before use. The components of the non-polar solvents may be the same or different, and there is no special requirement.

Various reaction raw materials of the present invention or the preferred scope of the mol ratio of reagent are as shown in table 1:

Table 1. The preferred molar ratios of various reaction raw materials or reagents

In the above table, when the allylpalladium chloride in the catalyst used is replaced by its dimer, the amount is 0.025 molar equivalent.

The method of the present invention has no strict restrictions on the proportion of the non-polar solvent, as long as the reaction solution can be stirred uniformly, preferably 1 mmol of compound (I) is dissolved in a non-polar solvent with a volume of not less than 5 mL.

The reaction time of each step of the method of the present invention is slightly different according to different raw materials, and is generally 6-24 hours based on the detection and disappearance of raw materials.

The present invention adopts oil bath (such as silicone oil, paraffin oil, etc.) or other ways to heat, as long as it is maintained at the reaction temperature.

The present invention can carry out post-treatment to the reaction solution obtained after the reaction, and post-treatment is usually filtering, then washes the filter residue with ethyl acetate, and combines the washing liquid with the filtrate, and then simply concentrates the filtrate, and the process of concentrating the filtrate adopts atmospheric distillation, Distill under reduced pressure or evaporate with a rotary evaporator.

In order to obtain a product with higher purity, it is preferable to purify the post-treated product. In the purification process, a certain polar solvent can be used as an eluent, and the chromatographic column separation is sufficient. The selected eluent varies according to the polarity of the product. In general, the eluent is a mixed solvent of petroleum ether and ethyl acetate, with a volume ratio of 1: (0.001-0.02). The chromatographic column used is such as the silica gel column commonly used in the laboratory or the high performance liquid chromatography column, etc., and the silica gel used is 200-300 mesh.

The present invention utilizes 2-(trimethylsilyl) aryl trifluoromethane sulfonate derivatives to react with alkynes, under the action of a catalyst, to prepare multi-substituted silacyclopentadiene (silole) derivatives, and the yield is relatively high. High, the synthesis method is scientific and reasonable, thus providing a general method for the synthesis of silacyclopentadiene derivatives with various substituents. The method has easy-to-obtain raw materials, wide application range, high separation yield, simple experimental equipment and operation, and is convenient for further development and application.

detailed description

The present invention is further described below in conjunction with embodiment, but does not limit the scope of the present invention in any way.

Example 1 - Preparation of the compound of formula IVa (R ¹ =H, R ² =R ³ =Ph):

Under nitrogen protection, in a 50mL reaction tube, add 1mmol of 2-(trimethylsilyl)phenyltrifluoromethanesulfonate, 1.2mmol of tolan, 0.05mmol of allyl palladium chloride, 0.1mmol of Tri-tert-butylphosphine, 3 mmol of lithium ethoxide, 2 mmol of potassium bromide and 5 mL of toluene solvent. The reaction temperature was kept constant at 120° C. for 24 hours using an oil bath. After cooling and filtering, the filtrate was concentrated to obtain the crude product. The crude product was decolorized and separated on a silica gel column, and petroleum ether was used as the eluent to obtain 250 mg of 1,1-dimethyl-2,3-diphenylbenzosilole (purity>98%, colorless solid). The rate is 80%. The NMR data of the compound are as follows: ¹ HNMR(400MHz, CDCl ₃ )δ:0.47(s,6H,CH ₃ ),6.96-6.99(m,2H,CH),7.04-7.07(m,2H,CH),7.11 -7.14(m,2H,CH),7.18-7.21(m,2H,CH),7.26-7.34(m,5H,CH),7.60-7.62(m,1H,CH); ¹³ CNMR(100MHz,CDCl ₃ )δ: -3.51(2CH ₃ ),123.98,125.66,126.65,127.05,127.93(2CH),128.34(2CH),128.59(2CH),129.66(2CH),129.76,131.62,138.13,138.16,139.999,142 150.71, 153.12.

Example 2—Preparation of the compound of formula IVb (R ¹ =OMe, R ² =Ph, R ³ =TMS):

Under nitrogen protection, add 1mmol of 2-(trimethylsilyl)-3-methoxyphenyltrifluoromethanesulfonate, 1.2mmol of phenylethynyltrimethylsilane, 0.05mmol in a 50mL reaction tube Allylpalladium chloride, 0.1mmol of tri-tert-butylphosphine, 3mmol of lithium ethoxide, 2mmol of potassium bromide and 5mL of xylene solvent. The reaction temperature was kept constant at 120° C. for 24 hours using an oil bath. After cooling and filtering, the filtrate was concentrated to obtain the crude product. The crude product was decolorized and separated on a silica gel column, and petroleum ether was used as the eluent to obtain 220 mg of 1,1-dimethyl-2-(trimethylsilyl)-3-phenyl-7-methoxybenzosilole ( Purity>98%, colorless oily liquid), isolated yield 65%. The NMR data of this compound are as follows: ¹ HNMR(400MHz, CDCl ₃ )δ: 0.49(s,6H,CH ₃ ),3.85(s,3H,CH ₃ ),6.69(d,J=7.5Hz,1H,CH) ,6.76(d,J=8.2Hz,1H,CH),6.96-6.98(m,2H,CH),7.04-7.32(m,9H,CH); ¹³ CNMR(100MHz,CDCl ₃ )δ:-4.03( 2CH ₃ ),55.41,109.03,117.41,123.60,125.57,126.93,127.87(2CH),128.22(2CH),128.57(2CH),129.68(2CH),131.87,138.32,140.07,143.85,152.32

Example 3 - Preparation of the compound of formula IVc (R ¹ =2F, R ² =R ³ =Ph):

Under nitrogen protection, add 1 mmol of 2-(trimethylsilyl)-4,5-difluorophenyltrifluoromethanesulfonate, 2 mmol of tolan, and 0.025 mmol of chlorinated alkenes into a 50 mL reaction tube Propyl palladium dimer, 0.1 mmol of tri-tert-butylphosphine, 2 mmol of lithium ethoxide, 1 mmol of tetramethylammonium bromide and 6 mL of 1,4-dioxane solvent. The reaction temperature was kept constant at 120° C. for 12 hours using an oil bath. After cooling and filtering, the filtrate was concentrated to obtain the crude product. The crude product was decolorized and separated on a silica gel column, and petroleum ether was used as the eluent to obtain 174 mg of 1,1-dimethyl-3,4-diphenyl-5,6-difluorobenzosilole (purity>98% , white solid), isolated in 50% yield. The NMR data of this compound are as follows: ¹ HNMR(CDCl3,399.78MHz)δ:0.47(s,9H),6.85(dd,JH-F=11.8Hz,JH-F=7.6Hz),6.93-6.96(m,2H ),7.06-7.17(m,5H),7.28-7.38(m,4H); ¹³ CNMR(CDCl3,100.53MHz)δ:-3.62,113.4(d,JC-F=18.2Hz),120.2(d,JC -F=16.3Hz),126.0,127.5,128.0,128.5,128.6,129.4,134.5(t,JC-F=3.9Hz),137.4,139.3,143.8(d,JC-F=3.8Hz),147.6(dd ,JC-F=5.3Hz,JC-F=3.8Hz),149.7(dd,JC-F=258Hz,JC-F=13.0Hz),151.3,151.5(dd,JC-F=248Hz,JC-F= 13.0Hz).

Example 4—Preparation of the compound of formula IVd (R ¹ =OMe, R ² =R ³ =2-Thenyl):

Under nitrogen protection, 1 mmol of 2-(trimethylsilyl)-3-methoxyphenyl trifluoromethanesulfonate, 1.2 mmol of bis(2-thiophene)acetylene, 0.025 mmol of Allyl palladium chloride dimer, 0.1 mmol of tri-tert-butylphosphine, 1 mmol of lithium ethoxide, 1 mmol of tetramethylammonium bromide and 8 mL of toluene solvent. The reaction temperature was kept constant at 120° C. for 24 hours using an oil bath. After cooling and filtering, the filtrate was concentrated to obtain the crude product. The crude product was decolorized and separated on a silica gel column, and petroleum ether was used as the eluent to obtain 258 mg of 1,1-dimethyl-3,4-bis(2-thiophene)-7-methoxybenzosilole (purity>98 %, white solid), the isolated yield was 73%. The NMR data of this compound are as follows: ¹ HNMR(400MHz, CDCl ₃ )δ: 0.57(s,6H,CH ₃ ),3.85(s,3H,CH ₃ ),6.63(d,J=7.5Hz,1H,CH) ,6.75(d,J=8.2Hz,1H,CH),6.93-7.02(m,3H,CH),7.16-7.22(m,2H,CH),7.28(t,J=7.9Hz,1H,CH) ,7.54(dd,J=5.1,0.9Hz,1H,CH); ¹³ CNMR(100MHz,CDCl ₃ )δ:-3.30(2CH ₃ ),55.43,109.01,117.07,121.78,126.14,127.07(2CH),127.87 ,127.93,128.06,132.36,138.10,139.90,141.57,142.54,153.06,162.85.

Example 5——Preparation of the compound of formula IVe (R ¹ =Naph, R ² =R ³ =Ph):

Under nitrogen protection, in 50mL reaction tube, add 1mmol of 2-(trimethylsilyl)-naphthyltrifluoromethanesulfonate, 1mmol of tolan, 0.025mmol of allyl palladium chloride dimer, 0.1 mmol of tri-tert-butylphosphine, 3 mmol of lithium ethoxide, 1 mmol of potassium bromide and 7 mL of toluene solvent. The reaction temperature was kept constant at 120° C. for 24 hours using an oil bath. After cooling and filtering, the filtrate was concentrated to obtain the crude product. The crude product was decolorized and separated on a silica gel column, and petroleum ether was used as the eluent to obtain 210 mg of 1,1-dimethyl-3,4-diphenylnaphthosilole (purity>98%, white solid), and the isolated yield was 58%. The NMR data of this compound are as follows: ¹ HNMR(400MHz, CDCl ₃ )δ:0.52(s,6H,CH ₃ ),7.00-7.16(m,6H,CH),7.23-7.27(m,1H,CH),7.33 -7.42(m,6H,CH),7.64-7.67(m,1H,CH),7.81-7.83(m,1H,CH),8.06(m,1H,CH); ¹³ CNMR(100MHz,CDCl ₃ )δ :-2.87(2CH ₃ ),122.43,125.75,125.79,126.47,127.15,127.82,127.95(2CH),128.39(2CH),128.45,128.58(2CH),129.77(2CH),132.37,132.649,134.5 138.20, 140.07, 144.72, 147.55, 153.65.

Example 6——Preparation of the compound of formula IVf (R ¹ =OMe, R ² =R ³ =1-Naph):

Under nitrogen protection, add 1mmol of 2-(trimethylsilyl)-3-methoxyphenyltrifluoromethanesulfonate, 1.2mmol of dinaphthyne, and 0.025mmol of allyl chloride in a 50mL reaction tube based palladium dimer, 0.1 mmol of tri-tert-butylphosphine, 3 mmol of lithium ethoxide, 2 mmol of potassium bromide and 10 mL of toluene solvent. The reaction temperature was kept constant at 120° C. for 24 hours using an oil bath. After cooling and filtering, the filtrate was concentrated to obtain the crude product. The crude product was decolorized and separated on a silica gel column, and petroleum ether was used as the eluent to obtain 296 mg of 1,1-dimethyl-3,4-dinaphthyl-7-methoxybenzosilole (purity>98%, white solid), with an isolated yield of 67%. The NMR data of the compound are as follows: ¹ HNMR (400MHz, CDCl ₃ ) δ: 0.46(s,3H,CH ₃ ),0.49(s,3H,CH ₃ ),3.88(s,3H,CH ₃ ),6.27(d ,J=7.5Hz,1H,CH),6.77(d,J=8.2Hz,1H,CH),6.92(br,1H,CH),7.11-7.17(m,4H,CH),7.31-7.36(m ,4H,CH),7.45(d,J=8.2Hz,1H,CH),7.54(dd,J=7.6,1.3Hz,1H,CH),7.65-7.70(m,2H,CH),7.88(d ,J=7.6Hz,1H,CH),8.01(d,J=7.3Hz,1H,CH); ¹³ CNMR(100MHz,CDCl ₃ )δ:-4.13,-3.69,55.43,109.11,117.97,123.72,124.86 ,125.23,125.27,125.35(2CH),125.42(3CH),125.63,126.58,126.67,127.26,127.94,128.05,131.58,131.84,132.09,133.20,133.35,135.93,138.56,146.97,152.40,153.34,162.99.

Example 7—Preparation of the compound of formula IVg (R ¹ =OMe, R ² =R ³ =4-FPh):

Under nitrogen protection, add 1mmol of 2-(trimethylsilyl)-3-methoxyphenyltrifluoromethanesulfonate, 2mmol of bis(4-fluorophenyl)acetylene, 0.025mmol in a 50mL reaction tube Allylpalladium chloride dimer, 0.1mmol of tri-tert-butylphosphine, 2mmol of lithium ethoxide, 1.5mmol of tetramethylammonium bromide and 5mL of toluene solvent. The reaction temperature was kept constant at 120° C. for 24 hours using an oil bath. After cooling and filtering, the filtrate was concentrated to obtain the crude product. The crude product was decolorized and separated on a silica gel column, and petroleum ether was used as an eluent to obtain 223 mg of 1,1-dimethyl-3,4-bis(4-fluorophenyl)-7-methoxybenzosilole (purity >98%, white solid), isolated yield 59%. The NMR data of this compound are as follows: ¹ HNMR(400MHz, CDCl ₃ )δ: 0.47(s,6H,CH ₃ ),3.86(s,3H,CH ₃ ),6.66(d,J=7.5Hz,1H,CH) ,6.77-6.91(m,5H,CH),7.01(t,J=8.8Hz,2H,CH),7.11-7.15(m,2H,CH),7.28(t,J=7.9Hz,H,CH) ; ¹³ CNMR(100MHz,CDCl ₃ )δ:-4.18(2CH ₃ ),55.43,109.22,114.96(d,J=21.0Hz,2CH),115.37(d,J=21.1Hz,2CH),117.19,123.38, 129.93(d,J _CF =7.8Hz,2CH),131.35(d,J _CF =7.8Hz,2CH),132.02,133.85(d,J _CF =3.4Hz),135.88(d,J _CF =3.5Hz), 143.41,151.39,151.95,160.24(d,J _CF =88.1Hz),162.69(d,J _CF =88.9Hz),163.05.

Example 8——Preparation of the compound of formula IVh (R ¹ =Me, R ² =R ³ =Ph):

Under nitrogen protection, 1 mmol of 2-(trimethylsilyl)-4-methylphenyltrifluoromethanesulfonate, 1.5 mmol of tolan, 0.025 mmol of allyl chloride were added to a 50 mL reaction tube Palladium dimer, 0.1 mmol of tri-tert-butylphosphine, 1 mmol of lithium ethoxide, 1 mmol of tetramethylammonium bromide and 5 mL of toluene solvent. The reaction temperature was kept constant at 120° C. for 24 hours using an oil bath. After cooling and filtering, the filtrate was concentrated to obtain the crude product. The crude product was decolorized and separated on a silica gel column, and petroleum ether was used as the eluent to obtain 183 mg of 1,1-dimethyl-3,4-diphenyl-6-methylbenzosilole (purity>98%, pale yellow solid), with an isolated yield of 56%. The NMR data of this compound are as follows: ¹ HNMR (400MHz, CDCl ₃ )δ: 0.46(s,6H,CH ₃ ),2.37(s,3H,CH ₃ ),6.93-6.98(m,3H,CH),7.03- 7.13(m,4H,CH),7.18-7.20(m,2H,CH),7.26-7.33(m,3H,CH),7.44(s,1H,CH); ¹³ CNMR(100MHz,CDCl ₃ )δ: -3.42(2CH ₃ ),21.21,123.80,125.51,126.96,127.89(2CH),128.29(2CH),128.59(2CH),129.59(2CH),130.26,132.60,136.30,138.21,138.32,11441.04,1 ,153.02.

Claims (9)

1. the synthetic method of a polysubstituted Silole derivative, it is characterized in that, that the alkynes shown in 2-(trimethyl silicane) the aryl trifluoro-methanyl sulfonate derivative shown in formula (I) and formula (II) is common and the catalyzer shown in formula (III) reacts in non-polar solvent, temperature of reaction is between 90 DEG C and the boiling point of described non-polar solvent, and described catalyzer is the mixture of chlorination Allylpalladium or its dipolymer, tri-tert phosphorus, lithium ethoxide and Potassium Bromide or 4 bromide;

Wherein, R ¹, R ²and R ³represent substituted or non-substituted C independently of one another _1-12alkyl, C _3-12silylation, C _6-12aryl or C _2-5heterocyclic aryl.

2. synthetic method as claimed in claim 1, it is characterized in that, described non-polar solvent is selected from one or more in toluene, dimethylbenzene or Isosorbide-5-Nitrae-dioxane.

3. synthetic method as claimed in claim 1, is characterized in that, the molar equivalent of described 2-(trimethyl silicane) aryl trifluoro-methanyl sulfonate derivative (I) and alkynes (II) is than being 1:1-2.

4. synthetic method as claimed in claim 1, is characterized in that, chlorination Allylpalladium in described catalyzer (III), tri-tert phosphorus, lithium ethoxide, and the molar equivalent of Potassium Bromide is than being 0.05:0.1:1-3:1-2.

5. synthetic method as claimed in claim 1, is characterized in that, the reaction solution also comprised obtaining after reaction carries out aftertreatment, and described aftertreatment comprises to be filtered and filtrate and washings are merged after use ethyl acetate washing filter residue.

6. synthetic method as claimed in claim 5, is characterized in that, described aftertreatment also comprises the filtrate after by merging and concentrates, and concentration process adopts air distillation, underpressure distillation or evaporates with Rotary Evaporators.

7. synthetic method as claimed in claim 5, it is characterized in that, by chromatographic column separation and purification after-treatment products, purifying eluent is the mixed solvent of sherwood oil and ethyl acetate, and described chromatographic column comprises silicagel column or performance liquid chromatographic column.

8. synthetic method as claimed in claim 7, it is characterized in that, the volume ratio of described eluent PetroChina Company Limited. ether and ethyl acetate is 1:0.001-0.02.

9. synthetic method as claimed in claim 7, it is characterized in that, the silica gel in described silicagel column is 200-300 order.