N. P. Kharitonov

Synthesis of triorganylchlorosilanes by catalytic reaction of triorganylsilanes with chlorobenzene

A study was made of the reaction for replacing the hydrogen atom, attached to the silicon in triorganylsilanes, by the chlorine atom when reaction is with chlorobenzene in the presence of colloidal nickel as the catalyst. A probable scheme of the reaction mechanism is given.

Basic characteristics of the Raman lines in the spectra of tripropyl- and ethyldipropylsilanes

1. The frequencies, integral intensities, coefficients of scattering S and R, degrees of depolarization, and half-widths of the lines in the Raman spectra of tripropyl- and ethyldipropylsilanes, containing normal and branched C3H7 groups, were measured. The vibrational spectra were interpreted. The invariants of the tensor of the derivative of the polarizability were calculated. For the Stokes waves, ν(Si-H) the absolute cross sections of spontaneous Raman scattering were determined at exciting frequencies of 22,938 and 14,403 cm−1. 2. The vibrationν(Si-H) (2090–2100 cm−1) is extremely characteristic in frequency, shape, intensity, and other parameters. The coefficient of scattering S varies within the range 6.1–7.0 units of the cyclohexane seals. 3. The origin of the frequencies ν(C-H) is explained on the basis of a consideration of the internal coordinates and the nature of the intrinsic functions of the ≡CH, =CH2, and −CH3 groups.

Protection of compressor coolers from corrosion

This article reports on the introduction of organosilicate compositions for anticorrosion protection of high-pressure compressor coolers and the replacement of stainless steel by carbon steel in the coolers of air and oxygen compressors without lubricant. The tubes of high-pressure coolers (tube-in-tube type) of high-pressure compressors are damaged by pitting and point corrosion from the action of the return water. The investigated high-pressure tubes were produced from 20Kh3MVF steel. It is established that organosilicate-composition protective coatings have satisfactory corrosion resistance in the cooling (return) water of high-pressure compressor coolers and in the gaseous media (air and oxygen) of reciprocating compressors without lubricant.

1-(Triorganylsilyl)-2-(triethoxysilyl)ethanes

The conditions were found for the hydrosilylation of CH2=CHSi(OC2H5)3 with triorganylsilanes in the presence of H2PtCl6 · 6H2O in isopropanol, which assured a high yield (>90%) of the 1-(triorganylsilyl)-2-(tri-ethoxysilyl)ethanes. These conditions were used to synthesize 27 new 1-(triorganylsilyl)-2-(triethoxysilyl)-ethanes.

Composition of products from tribochemical conversions of organosilicon isomers, as studied by mass spectrometry

Summary1.Mass spectrometric analysis has been used in studying the products from tribochemical conversions of two organosilicon fluids, i.e., m- and p-bis(methyl-di-n-decylsiloxy)benzenes.2.It has been established that the p isomer, in comparison with the m isomer, has a longer operating life in the model rolling-friction unit.3.It has been shown that the tribochemical conversions of the test fluids form new substances with molecular weights from 94 to 958. The products from tribochemical reactions of the p isomer, in comparison with the m isomer, are characterized by higher contents of iow-molecular-weight olefinic hydrocarbons and alkylsiloxybenzenes with short alkyl side chains, as well as by a new substance with a molecular weight higher than the original.

Reaction of triethylsi lane with unsaturated mono- and dicarboxylic acids

Two consecutive reactions, dehydrocondensation and hydrogenation, take place when triethylsilane is reacted with the cinnamic and fumaric acids in the presence of colloidal nickel.

Vibrational spectra of trialkysilanes of the series (CH3)n (C2 H5)3−n SiH

1. The vibrational spectra of dimethylethyl-, and methyldiethyl-, and triethylsilane were investigated. The frequencies, integral and standard intensities, degrees of polarization, and half-widths of the lines were measured in the Raman spectra. The qualitative intensities and the positions of the bands for the solid, liquid, and gaseous phases were determined in the IR spectra. 2. The spectrographic peculiarities of the Si-H bond were studied. 3. The potential functions were calculated for the tetrahedral framework of the molecules.

Reaction of pentaerythritol with trialkylsilanes in presence of certain metal halides

1. A study was made of the reaction of trialkylsilanes with pentaerythritol in presence of certain metal halides. The reaction rate depends on the structure of the trialkylsilane and the amount of catalyst. 2. The infrared absorption spectra of the silyl derivatives of pentaerythritol obtained in the region 3600-3100 cm−1 indicate the presence of both inter- and intra-molecular hydrogen bonds, which explains the low reactivities of the unsubstituted hydroxy groups.

Catalytic reaction of trialkyl(aryl)silanes with allyl alcohol

1. A study has been made of the catalytic reaction between trialkyl(aryl)silanes and allyl alcohol in the presence of small additions of alkali metals or of zinc and tin halides. 2. A convenient method has been developed for preparing 3-trialkyl(aryl)siloxypropenes-1 through trialkyl(aryl)silanes, with a yield up to 80% of the theoretical. 3. Confirmation has been obtained for the regularities found earlier in the effect of trialkyl (aryl)silane radicals and the nature of the catalyst on the reaction rate. 4. Eleven trialkyl(aryl)allyloxysilanes have been synthesized for the first time.

Reaction of trialkylsilanes with phenol in the presence of metal halides

We studied the reaction of phenol with trialkylsilanes of various structures, catalyzed by metal halides. The most suitable halides for this reaction are those of Cr, Co, Ni, Ge, Zn, Sn, and Hg. The reaction rate depends on the structure of the trialkylsilane and the amount and nature of the metal halides.