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On the basis of analysis of product composition in the hydrolytic polycondensation (HPC) of chlorotriorganosilanes, the parameters of the kinetic and the diffusion field, the zone of the reaction, and the region of the conodes of the phase diagrams are determined. It is suggested that the conodes correspond to a phase quasiequilibrium, which defines the composition of the reaction products. The results of this investigation confirm the previously discovered features of HPC of dichloromethylphenylsilanes: the formation of the siloxane bond during the hydrolysis of chloroorganosilanes by water mainly occurs in the organic phase of the system and proceeds as the heterofunctional polycondensation of the reaction products with the starting chloroorganosilanes. The role of the phase quasiequilibrium consists of the creation of a field of reagent concentration, based on which one can control the composition of the reaction products.

-- The physical transitions in PAN-NaSCN-H2O mixtures at weight ratios of NaSCN:H2O=51.5:48.5 and 45:55) have been studied by the DTA method in the temperature range 80–400 K. Physical-state diagrams have been constructed from the results of these studies.

Abstract: Auto-oscillations were discovered by TLC in a study of the condensation of RR'Si(OH)2 (R=R′=Me, Et, Ph; R=Me, R′=CH2=CH, Ph, OH) in aqueous organic solvents in the pH range −1–15 up to large degrees of conversion of the monomer (70–100%). The process is characterized by complicated profiles of the kinetic curves containing sections of acceleration and deceleration of the reaction. The nonequilibrium character of the process was established. It was assumed that the phenomena observed arise as a result of association of the monomer and oligomers during the reaction.

The condensation of the thiuronium salt from 1-vinyl-6-methoxy-1-tetralol with 2-(carbethoxymethyl)-dihydroresorcinol smoothly gives the 18-carbethoxysecosteroid (III), from which, depending on the reaction conditions, the 18-carbethoxy derivatives of D-homoequilenin or D-homoestrone can be obtained by acid cyclization.