Kathleen Schmohl, Dirk Wandschneider, H. Reinke
Mar 1, 2002
Citations
0
Influential Citations
3
Citations
Journal
European Journal of Inorganic Chemistry
Abstract
(3-Hydroxy-1-propenyl)tris(trimethylsilyl)silanes (Me3Si)3SiCH=CHCR2OH (8b,c) (b: R = Me; c: R = Ph) undergo a rapid rearrangement involving a 1,2-Si,C migration of one trimethylsilyl group from the central silicon atom to a cationic neighboring carbon atom and a shift of the olefinic double bond, in the presence of acid, to afford (1-trimethylsilyl-2-propenyl)bis(trimethylsilyl)silanols (Me3Si)2Si(OH)CH(SiMe3)CH=CR2 (13b,c). Treatment of 8b,c with sulfuric acid in methanol gives the methoxysilanes (Me3Si)2Si(OMe)CH(SiMe3)CH=CR2 (14b,c). In a related reaction, 8b,c are converted by boron trifluoride into the fluorosilanes (Me3Si)2SiFCH(SiMe3)CH=CR2 (15b,c). A possible mechanism of the isomerization reaction, involving the rearrangement of the silylcarbenium ions [(Me3Si)3SiCH=CHCR2]+ into the silylium ions [(Me3Si)2SiCH(SiMe3)CH=CR2]+, is proposed. This is supported by calculations, which indicate the higher stability of the silylium ion 10b compared with the isomeric silylcarbenium cation 9b. For 14c the results of an X-ray structural analysis are given.