RU2434015C1 - Method of producing oligoorganocarbodiimido silanes - Google Patents

Abstract

FIELD: chemistry. ^ SUBSTANCE: invention relates to synthesis of organosilicon oligomers with a carbodiimide structure, which are common precursors during production of porous ceramic materials. Disclosed is a method for synthesis of oligoorganosilyl carbodiimides via polycondensation of 2.5-3.0-fold excess N,N'-bis(trimethylsilyl)-carbodiimide with organochlorosilanes in the presence of a catalyst. ^ EFFECT: thorough binding of terminal chlorine atoms into removable products at the pyrolysate devolatilisation step in a vacuum. ^ 1 cl, 1 tbl, 2 ex

Description

The present invention relates to the field of obtaining silicofunctional organic compounds of General formula (I)

- продукты финишной керамизации (кальцинирования) до безоксидной пористой керамики, сохраняющей в структуре композита карбодиимидные

и изомерные цианамидные

группировки [Riedel, R. Non-oxide silicon-based ceramics from novel silicon polymers / R. Riedel, A. Kienzle, M. Frieb in book Applications of organometallic chemistry in the preparation and processing of advanced materials [Ed. J.F. Harrod, R.M. Line. - France]. Nato asi Series, Ser.E: Appl.Sci. - Vol.297. - Kluwer Acad. PubL, Dordrecht / Boston / London, 1995. - P.155-171].Carbodiimides (I) are generally accepted precursors in the preparation of porous ceramic materials with a well-defined group of Si-NCN atoms, which provide a controlled process of a stepwise transition of the prepolymer - network polymer - deorganized pyrolyzate

- products of finishing ceramization (calcination) to an oxide-free porous ceramic that retains carbodiimide in the composite structure

and isomeric cyanamide

groupings [Riedel, R. Non-oxide silicon-based ceramics from novel silicon polymers / R. Riedel, A. Kienzle, M. Frieb in book Applications of organometallic chemistry in the preparation and processing of advanced materials [Ed. JF Harrod, RM Line. - France]. Nato asi Series, Ser.E: Appl.Sci. - Vol. 297. - Kluwer Acad. PubL, Dordrecht / Boston / London, 1995. - P.155-171].

The quality of the resulting mixtures of carbide, nitride and carbonitride determines the quality of products based on them. To ensure a high level of technical parameters of oxide-free powders, the process at all stages of the technological redistribution is carried out in an inert gas atmosphere and, no less important, they strive to exclude as much as possible chlorine impurities from the process, which can be introduced from the stage of non-perfect completeness of the catalytic re-alkylation of the initial N, N 'bis (trimethylsilyl) carbodiimide diorganodichlorosilanes.

A known method of producing oligoorganocarbodiimidosilanes by polycondensation of N, N'-bis (trimethylsilyl) carbodiimide with organochlorosilanes in the presence of a catalyst [Riedel, R. The first crystalline solids in the ternary Si-CN system / R. Riedel, A. Greiner, G. Mieche / / Angew. Chem. Int. Ed. Engl. - 1997. - V.36. - No. 6. - P.603-606].

The disadvantage of this method is: the duration and the need to remove terminal chlorine atoms.

The closest in technical essence and the achieved result is a method for producing polyorganosilylcarbodiimides by polycondensation of N, N'-bis (trimethylsilyl) carbodiimide with organosilicon compounds - organochlorosilanes - in the presence of a catalyst and organosilazanes.

[Kolesnikova, A.B. Synthesis and modification of polysilylcarbodiimides / A.B. Kolesnikova, M.Yu. Mitrofanov, E.A. Gruzinova, A.M. Muzafarov // High-molecular compounds. - Series A. - 2007. - T. 49. - No. 9. - S.1628-1634].

The disadvantage of this method is the length of the process and the need to remove terminal chlorine atoms by organosilazanes.

The technical result of the present invention is the reduction of the stages of synthesis and the elimination of the formation of terminal chlorine atoms in the final oligoorganocarbodiimidosilane.

The technical result is achieved by polycondensation of N, N'-bis (trimethylsilyl) carbodiimide with organochlorosilanes when heated in the presence of a catalyst until the release of low molecular weight products is stopped and then evacuated. The process is carried out with a 2.5-3.0-fold excess of N, N'-bis (trimethylsilyl) carbodiimide.

Example 1

57.2 g (0.31 mol) of N, N'-bis (trimethylsilyl) carbodiimide and 15.5 g (0.12 mol) of dimethyldichlorosilane were charged into a flask equipped with a thermometer, a complete condensation head and a continuous supply of nitrogen. The reaction mass was heated until the release of trimethylchlorosilane was stopped, evacuated to completely remove low boiling products, and oligodimethylsilylcarbodiimide was isolated. IR spectrum (ν, cm ^-1 ): 2140-2180 (C = N). ¹ H NMR spectrum, δ, ppm: 0.21 (s, 32H, SiCH ₃ ). Found,%: C 41.13; H 5.21; N, 23.82; Cl 0. M 544. C ₁₉ H ₃₂ N ₁₀ S ₁₆ . Calculated,%: C 40.10; H 5.70; N, 24.62. M 596.

Example 2

A flask equipped with a thermometer, a complete condensation head and a continuous supply of nitrogen was charged with 44.5 g (0.24 mol) of N, N'-bis (trimethylsilyl) carbodiimide and 18.3 g (0.096 mol) of methyl phenyl dichlorosilane. The reaction mass was heated until the release of trimethylchlorosilane was stopped, evacuated to completely remove low boiling products, and oligomethylphenylsilylcarbodiimide was isolated. IR spectrum (ν, cm ^-1 ): 2140-2180 (C = N). ¹ H NMR spectrum, δ, ppm: 0.21 (s, 30H, SiCH ₃ ). Found,%: C 56.94; H 5.71; N, 16.82; Cl 0. M 803. C ₃₉ H ₄₀ N ₁₀ S ₁₆ . Calculated,%: C 56.62; H 6.09; N, 16.93. M 827.3.

The rest of the experiments were carried out similarly (3-5), where methyldichlorosilane, methylvinyl dichlorosilane, diphenyldichlorosilane were used as starting reagents (see table).

Physicochemical properties No pp Source IR spectrum Mn _Compute Gross- Mn _found. organochlorosilane (ν, cm ^-1 ) formula one Me ₂ SiCl ₂ 2140-2180 596 C ₁₉ H ₃₂ N ₁₀ Si ₆ 544 2 MePhSiC ₂ 2140-2180 827.3 C ₃₉ H ₅₀ N ₁₀ Si ₆ 803 3 MeHSiCl ₂ 2140-2180 523 C ₁₅ H ₃₄ N ₁₀ Si ₆ 516 four MeVinSiCl ₂ 2140-2180 627.1 C ₂₃ H ₄₂ N ₁₀ Si ₆ 618 5 Ph ₂ SiCl ₂ 2140-2180 444.6 C ₂₆ H ₂₀ N ₄ Si ₂ 465

This invention will find application in the preparation of chlorine-free organo-carbocarbodiimidosilanes, which, in turn, are used in the manufacture of insulating coatings and components of high-temperature products, and are also used to create nanostructured composite and ceramic materials.

Claims (1)

A method of producing oligoorganosilylcarbodiimides by polycondensation of N, N'-bis (trimethylsilyl) -carbodiimide with organochlorosilanes by heating in the presence of a catalyst until the evolution of low molecular weight products ceases and then evacuating, characterized in that the process is carried out with a 2.5-3.0 fold excess of N, N'-bis (trimethylsilyl) carbodiimide.