Preparation method of adamantyl-containing silane or siloxane

Abstract

The invention discloses a preparation method of silane or siloxane containing adamantyl. According to the invention, adamantane carboxylic acid is taken as a starting raw material, an adamantane compound containing double bonds at the tail end is obtained through an esterification reaction, and then the adamantane compound and hydrogen-containing silane or hydrogen-containing siloxane are subjected to a hydrosilylation reaction to prepare adamantyl-containing silane or siloxane. The method is mild in reaction condition, simple, convenient and easy to operate, capable of achieving preparation of adamantyl silane or siloxane of various structures, wide in application range and capable of providing diversified choices for development of novel adamantyl modified organic silicon materials.

Description

Technical Field

[0001] The present invention relates to a method for preparing a silane or siloxane containing an adamantyl group, and belongs to the technical field of organosilicon synthesis. Background Art

[0002] Silanes and siloxanes are important low-molecular organosilicon compounds. As low-molecular compounds, they can be directly used as coupling agents and water repellents in surface treatment; as precursors for chemical vapor deposition, they are used to manufacture silicon thin films and silicon dioxide layers; as tackifiers, they can improve the adhesion to substrates; they can also be used as defoamers and lubricants in coatings, inks and high-temperature environments. As monomers, silanes and siloxanes are important raw materials for synthesizing organosilicon polymer materials. Organosilicon materials have properties such as insulation, high temperature resistance, anti-aging, chemical corrosion resistance, physiological inertness and ultraviolet radiation resistance, and are widely used in fields such as daily chemicals, aerospace, automobiles, and household appliances. With the development of high-tech, higher requirements are put forward for the properties of organosilicon compounds and organosilicon materials. Therefore, it is necessary to design and synthesize new silane and siloxane compounds to prepare high-performance organosilicon materials.

[0003] Adamantane is a polycyclic cage-like hydrocarbon compound with a cyclic tetrahedral structure and high symmetry. It is one of the hydrocarbons with the highest known melting point, with a melting point of 269 °C and the molecule has diamagnetism. Its basic structure is composed of three fused chair cyclohexane rings, with a unique rigid but strain-free ring system, and the molecule is completely unaffected by angle strain and torsional strain. Introducing an adamantyl group into a polymer material, due to its unique structure, it can improve the properties of the polymer, that is: it can improve the conductivity of polymethylthiophene, the glass transition temperature and thermal stability of polymethyl methacrylate, etc. Due to the reversibility of the host-guest interaction between β-cyclodextrin and adamantane, the adamantyl group has also been applied to self-healing hydrogels and shows self-healing properties in both wet and dry states.

[0004] Feng Yakai et al. used 1-adamantylmethanol and 3-isocyanatopropyltrimethoxysilane as raw materials, introduced the adamantyl group into the silane compound under the catalysis of stannous octoate, and then synthesized an adamantane-modified silicone resin material. With the increase of the adamantane content, the refractive index of the resin increases and it can be used in the field of LED packaging. However, the silane raw material in this synthesis method must contain an isocyanate group, and its synthesis often requires highly toxic phosgene, resulting in a large limitation in the selectivity of silane. This method also requires the use of highly toxic stannous octoate, and it will remain in the polymer material, which is very unfavorable to the material performance, material use and environmental protection (Feng Yakai et al., Preparation and properties of adamantane-modified silicone LED packaging materials [J]. Journal of Tianjin University, 2019, 52: 129). Zhao Xi et al. made 1-bromoadamantane react with benzene, and then brominated it to generate tetra(4-bromophenyl)adamantane. This product reacts with chlorosilane under the action of tert-butyllithium to connect the adamantane and siloxane, and a new type of silicon flame retardant is obtained (Zhao Xi et al., Synthesis of a new type of phosphorus-silicon flame retardant and its flame retardant properties for polycarbonate [J]. Metallurgy and Materials, 2019, 39: 25). This method requires the use of highly toxic benzene and tert-butyllithium that ignites spontaneously when exposed to air, and the synthesis route is long, the process is complex, and it involves experimental conditions such as -78 °C, which is not easy to implement.

[0005] After retrieval, there is currently no report on the preparation of silane or siloxane containing adamantyl group through hydrosilylation reaction. Summary of the Invention

[0006] The object of the present invention is to overcome the above deficiencies and provide a method for preparing silane or siloxane containing adamantyl group. The present invention uses adamantane carboxylic acid as the starting material, obtains an adamantane compound with a double bond at the end through an esterification reaction, and then prepares silane or siloxane containing adamantyl group through a hydrosilylation reaction with hydrosilane or hydrosiloxane. The reaction conditions of the present invention are mild, simple and easy to operate, can realize the preparation of silane or siloxane with various structures of adamantyl group, have a wide application range, and provide a diversified selection for the development of new adamantane-modified silicone materials.

[0007] The technical solution of the present invention is: a method for preparing silane or siloxane containing adamantyl group, characterized in that, using adamantane carboxylic acid as the starting material, obtaining an adamantane compound with a double bond at the end through an esterification reaction, and then preparing silane or siloxane containing adamantyl group through a hydrosilylation reaction with hydrosilane or hydrosiloxane.

[0008] Specifically, it includes the following steps:

[0009] (1) Using adamantane-1-carboxylic acid and 4-penten-1-ol as raw materials, dissolve them together with a catalyst in solvent A, add a dehydrating agent dropwise at room temperature, and react at room temperature for 4 - 10 h after the addition is complete; after the reaction is completed, add solvent B to dilute and promote the precipitation of by-products, filter, and concentrate the filtrate, then separate by column chromatography to obtain tricyclo[3.3.1.1 3,7 decane-1-carboxylic acid pent-4-enyl ester;

[0010]

[0011] In the above steps, the dehydrating agent is N,N'-diisopropylcarbodiimide, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide or N,N'-dicyclohexylcarbodiimide; the catalyst is 4-dimethylaminopyridine; solvent A is a polar solvent such as dichloromethane or chloroform, preferably dichloromethane; solvent B is a non-polar solvent such as petroleum ether, n-hexane or n-heptane, preferably petroleum ether.

[0012] In the above steps, the molar ratio of adamantane-1-carboxylic acid, 4-penten-1-ol, the catalyst and the dehydrating agent is 1:1 - 1.5:0.05 - 0.15:1 - 1.5.

[0013] (2) Add tricyclo[3.3.1.1 3,7 decane-1-carboxylic acid pent-4-enyl ester, hydrosilane or hydrosiloxane and a hydrosilylation catalyst into a reaction vessel (if the hydrosilane or siloxane is a liquid, no solvent needs to be added; if it is a solid, a solvent must be added to dissolve it before reaction), and heat the reactants at 80 - 130 °C for 2 - 7 hours under nitrogen protection; after the reaction is completed, separate by column chromatography to obtain the desired silane or siloxane product containing an adamantyl group.

[0014]

[0015] In the above steps, the molecular formula of the hydrosilane is RR ’ R”SiH, where R, R ’ , R” are the same or different and are alkyl, aryl or alkoxy; the molecular formula of the hydrosiloxane is HMe2SiO(Me2SiO) n SiMe2H or (CH3CH2O)3SiH, where n is an integer from 0 to 10, preferably 1 to 5. The hydrosilylation catalyst used is a platinum catalyst such as Karstedt catalyst or Speier catalyst, preferably Karstedt catalyst. The molar ratio of platinum in tricyclo[3.3.1.1 3,7 decane-1-carboxylic acid pent-4-enyl ester, hydrosilane or hydrosiloxane, and the hydrosilylation catalyst is 1:1 - 3:(1×10 -3 ~5×10 -3 ).

[0016] In the above preparation method, the solvent used in column chromatography is a mixed solvent of petroleum ether and ethyl acetate, and the volume ratio is 100:0 to 10:1 (when the value is 0, only petroleum ether is used).

[0017] The beneficial effects of the present invention are as follows:

[0018] (1) The raw materials are easily available, the reaction conditions are mild, the operation is simple and easy, without involving the use of highly toxic reagents and harsh reaction conditions, and it is suitable for industrial production;

[0019] (2) The preparation of silanes or siloxanes with various structural adamantyl groups can be realized, and the applicable range is wide, providing diversified choices for the development of new adamantane-modified silicone materials, and there is no heavy metal residue in the obtained silicone materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figures 1 to 3 It is the 1 1H NMR (CDCl3) spectrum of the products obtained in Examples 2, 3, and 5 of the present invention;

[0021] Figures 4 to 6 It is the 13 13C NMR (CDCl3) spectrum of the products obtained in Examples 2, 3, and 5 of the present invention;

[0022] Figures 7 to 9 It is the mass spectrum of the products obtained in Examples 2, 3, and 5 of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0023] The present invention will be further described below with reference to the examples.

[0024] Example 1: Preparation of pent-4-en-1-yl tricyclo[3.3.1.1 3,7 decane-1-carboxylate

[0025] Adamantane-1-carboxylic acid (129.4 g), 4-dimethylaminopyridine (8.4 g) and 4-penten-1-ol 89.5 ml were placed in a reaction flask and dissolved in 900 ml of dichloroethane to obtain a light yellow solution. At room temperature, 150 ml of N,N'-diisopropylcarbodiimide was added dropwise to the reaction flask, and the color of the reaction solution gradually became lighter. After the addition was completed, the reaction was stirred at room temperature for 8 h to obtain a light yellow turbid liquid. 500 ml of petroleum ether was added for dilution, and the mixture was filtered. The filtrate was concentrated to obtain a yellow liquid, and column chromatography (petroleum ether / ethyl acetate 100:0 to 50:1) was used to obtain 126 g of a colorless liquid, with a yield of 71% and a purity of ≥98%.

[0026] Example 2: Preparation of silane containing adamantyl group

[0027]

[0028] Tricyclo[3.3.1.1 3,7 decane-1-carboxylic acid pent-4-enyl ester (11.1 g), phenyl dimethylsilane (6.7 g), and 10 ml of xylene were added to a Schlenk reaction tube to obtain a colorless solution. Then, Karstedt catalyst (platinum content 0.11 mmol / ml, 0.4 ml) was added and stirred evenly. The mixture was evacuated and replaced with nitrogen three times, and then reacted in an oil bath at 110 °C for 7 h under nitrogen protection. The mixture after the reaction was separated by column chromatography (petroleum ether / ethyl acetate 15:1) to obtain 13.1 g of a colorless liquid product with a yield of 71% and a purity of ≥98%.

[0029] 1 1H NMR (400 MHz, CDCl3) δ 7.51 - 7.49 (m, 2H), 7.36 - 7.34 (m, 3H), 4.00 (t, J = 6.6 Hz, 2H), 2.00 (brs, 3H), 1.87 (d, J = 3.0 Hz, 6H), 1.74 - 1.67 (m, 6H), 1.61 - 1.55 (m, 2H), 1.36 - 1.33 (m, 4H), 0.77 - 0.73 (m, 2H), 0.25 (s, 6H).

[0030] 13 13C NMR (101 MHz, CDCl3) δ 177.9, 139.6, 133.7, 128.9, 127.9, 64.3, 40.8, 39.0, 36.7, 30.0, 28.5, 28.1, 23.8, 15.9, -2.9.

[0031] IR (KBr pellet) ν max 1725, 1453, 1233, 1077, 834 cm -1 .

[0032] HRMS-ESI calc. for C 24 H 36 NaSiO2 ([M+Na] + ) 407.2377, found 407.2359.

[0033] Example 3: Preparation of adamantyl-containing siloxane

[0034]

[0035] Tricyclo[3.3.1.1 3,7Decane-1-carboxylic acid pent-4-enyl ester (11.1 g) and triethoxysilane (9.9 ml) were added to a Schlenk reaction tube to obtain a colorless solution. Then Karstedt catalyst (platinum content 0.11 mmol / ml, 0.4 ml) was added and stirred evenly. The mixture was evacuated and replaced with nitrogen three times, and then reacted in an oil bath at 130 °C under nitrogen protection for 4 h. The mixture after the reaction was separated by column chromatography (petroleum ether / ethyl acetate 100:1) to obtain 16.8 g of a colorless liquid product with a purity of ≥98% and a yield of 98%.

[0036] 1 H NMR (400 MHz, CDCl3) δ 4.03 (t, J = 6.6 Hz, 2H), 3.81 (q, J = 7.0 Hz, 6H), 2.00 (brs, 3H), 1.88 (d, J = 3.0 Hz, 6H), 1.74 - 1.67 (m, 6H), 1.61 (quint, J = 7.1 Hz, 2H), 1.45 - 1.38 (m, 4H), 1.22 (t, J = 7.0 Hz, 9H), 0.66 - 0.62 (m, 2H).

[0037] 13 C NMR (101 MHz, CDCl3) δ 177.9, 64.2, 58.4, 40.8, 39.0, 36.6, 29.5, 28.4, 28.1, 22.6547, 18.4, 10.5.

[0038] IR (KBr) ν max : 2906, 1726, 1233, 1075, 956, 780 cm -1 。

[0039] HRMS-ESI calcd for C 22 H 40 NaO5Si([M+Na] + ) 435.2537, found: 435.2526.

[0040] Example 4: Preparation of silane containing adamantyl

[0041]

[0042] Tricyclo[3.3.1.1 3,7Decane-1-carboxylic acid pent-4-enyl ester (10.4 g), diphenylsilane (23.2 g), and 20 ml of xylene were added to a Schlenk reaction tube, and then Karstedt catalyst (platinum content 0.11 mmol / ml, 0.4 ml) was added and stirred evenly. It was purged with nitrogen three times, and then reacted in an oil bath at 130 °C for 2.4 h under nitrogen protection. The mixture after the reaction was separated by column chromatography (petroleum ether / ethyl acetate 100:0 to 20:1) to obtain 14.0 g of a colorless liquid. According to NMR calculation, it contained 25% of the unreacted adamantane olefin isomer, and the NMR yield was 44%.

[0043] Example 5: Preparation of Siloxane Containing Adamantyl Group

[0044]

[0045] Tricyclo[3.3.1.1 3,7 Decane-1-carboxylic acid pent-4-enyl ester (9.0 g) and 1,1,3,3-tetramethyldisiloxane (3.5 ml) were added to a Schlenk reaction tube, and then Karstedt catalyst (platinum content 0.11 mmol / ml, 0.3 ml) was added and stirred evenly. It was purged with nitrogen three times, and then reacted in an oil bath at 120 °C for 4 h under nitrogen protection. The mixture after the reaction was separated by column chromatography (petroleum ether / ethyl acetate 30:1) to obtain 6.3 g of a colorless liquid, with a yield of 67% and a purity of ≥98%.

[0046] 1 H NMR (400 MHz, CDCl3) δ 4.03 (t, J = 6.1 Hz, 4H), 2.00 (sept, J = 3.1 Hz, 6H), 1.88 (d, J = 3.0 Hz, 12H), 1.75 - 1.66 (m, 12H), 1.61 (quint, J = 6.9 Hz, 4H), 1.40 - 1.30 (m, 8H), 0.53 - 0.49 (m, 4H), 0.03 (s, 12H).

[0047] 13 C NMR (101 MHz, CDCl3) δ 177.9, 64.3, 40.8, 39.0, 36.6, 29.8, 28.5, 28.1, 23.11, 18.41, 0.5.

[0048] IR (KBr pellet) ν max 2905, 2851, 1726, 1453, 1231, 1103, 837, 782 cm -1 .

[0049] HRMS-ESI calcd for C36 H 62 NaO5Si2([M+Na] + )653.4028, found: 653.4023。

[0050] The above is a description of the preferred implementation of the present invention, but it is not a limitation on the protection scope of the present invention. Based on the technical solution of the present invention, various modifications or deformations that can be made by those skilled in the art without creative labor are still within the protection scope of the present invention.

Claims

1. A method for preparing a silane or siloxane containing an adamantyl group, characterized in that, Using adamantane carboxylic acid as the starting material, an adamantane compound with a double bond at the end is obtained through an esterification reaction, and then a silane or siloxane containing an adamantyl group is prepared through a hydrosilylation reaction with a hydrosilane or a hydrosiloxane.

2. The preparation method of a silane or siloxane containing adamantyl group according to claim 1, characterized in that, Specifically, the steps are as follows: (1) Using adamantane-1-carboxylic acid and 4-penten-1-ol as raw materials, dissolve them together with a catalyst in solvent A, add a dehydrating agent dropwise at room temperature, and react for 4 - 10 h at room temperature after the addition is complete; after the reaction is complete, add solvent B to dilute and promote the precipitation of by-products, filter, concentrate the filtrate, and separate it by column chromatography to obtain tricyclo[3.3.1.1 3,7 decane-1-carboxylic acid pent-4-enyl ester; (2) Add tricyclo[3.3.1.1 3,7 decane-1-carboxylic acid pent-4-enyl ester, hydrosilane or hydrosiloxane, and a hydrosilylation catalyst into a reaction vessel, and heat the reactants at 80-130 °C for 2-7 hours under nitrogen protection; after the reaction is completed, a silane or siloxane product containing an adamantyl group is obtained by column chromatography separation.

3. The preparation method of a silane or siloxane containing adamantyl group as claimed in claim 2, wherein, The molecular formula of the hydrogen-containing silane is RR ’ R”SiH, where R, R ’ , and R” are the same or different and are alkyl, aryl or alkoxy groups; the molecular formula of the hydrogen-containing siloxane is HMe2SiO(Me2SiO) n SiMe2H or (CH3CH2O)3SiH, where n is an integer from 0 to 10.

4. The preparation method of a silane or siloxane containing adamantyl group according to claim 2, characterized in that, The dehydrating agent in step (1) is N,N'-diisopropylcarbodiimide, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide or N,N'-dicyclohexylcarbodiimide; the catalyst is 4-dimethylaminopyridine.

5. The preparation method of a silane or siloxane containing adamantyl group according to claim 2, characterized in that, The solvent A in step (1) is a polar solvent; the solvent B is a non-polar solvent.

6. The preparation method of a silane or siloxane containing adamantyl group according to claim 5, characterized in that, The solvent A in step (1) is dichloromethane or chloroform; the solvent B is petroleum ether, n-hexane or n-heptane.

7. The preparation method of a silane or siloxane containing adamantyl as described in claim 2, characterized in that, The molar ratio of adamantane-1-carboxylic acid, 4-penten-1-ol, the catalyst and the dehydrating agent in step (1) is 1:1 to 1.5:0.05 to 0.15:1 to 1.

5.

8. The preparation method of a silane or siloxane containing an adamantyl group as described in claim 2, characterized in that, In step (2), the hydrosilylation catalyst used is a platinum catalyst.

9. The preparation method of a silane or siloxane containing adamantyl group according to claim 8, characterized in that, In step (2), the platinum catalyst used is Karstedt catalyst or Speier catalyst.

10. The preparation method of a silane or siloxane containing adamantyl as described in claim 2, characterized in that, The molar ratio of the tricyclo[3.3.1.1 3,7 decane-1-carboxylic acid pent-4-enyl ester, hydrosilane or hydrogen-containing siloxane, and platinum in the hydrosilylation catalyst is 1:1 to 3:(1×10 -3 to 5×10 -3 ).

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