New approach to the synthesis of linear and cyclic vinyl(alkoxy)siloxanes

详细

Main products of the reaction of vinyltrichlorosilane VinSiCl₃ with DMSO in the medium of tetra-(alkoxy)silane are linear siloxanes (RO)₃Si[OSiVin(OR)]OSi(OR)₃, RO[Vin(RO)SiO]_nSi(OR)₃ (R = Me, Et, n = 0–2) and the hitherto unknown cyclic siloxanes [Vin(RO)SiO]_m[(RO)₂SiO]_4–m (m = 1–3) formed in the ratio of 70: 30%. A tentative scheme of their formation is suggested with participation of the products of the alkoxy groups exchange between vinyl(alkoxy)dichloro-, vinyldi(alkoxy)chloro-, trialkoxychloro-, and dialkoxydichlorosilanes.