61777-06-8Relevant academic research and scientific papers
Carbonium Ion Rearrangements Controlled by the Presence of a Silyl Group
Fleming, Ian,Patel, Shailesh K.,Urch, Christopher J.
, p. 115 - 124 (2007/10/02)
γ-Silyl tertiary alcohols rearrange in protic acid with 1,2-shift of hydride, phenyl, or alkyl groups, and loss of the silyl group to give alkenes.The placing of the silyl group thus controls the carbonium ion rearrangement in a preparatively useful way.Methoxycarbonyl groups do not migrate; instead, cyclopropanes are formed, except when the conformation suitable for cyclopropane formation is unattainable.When the alkene product is 2,2-disubstituted, it can be reprotonated under the reaction conditions and does not therefore always survive.This can be avoided by carrying out the reaction using a Lewis acid on the silyl ether.The starting γ-silyl alcohols are prepared by a variety of versatile methods.
CARBONIUM ION REARRANGEMENTS CONTROLLED BY THE PRESENCE OF A SILYL GROUP
Fleming, Ian,Patel, Shailesh K.
, p. 2321 - 2324 (2007/10/02)
Tertiary alcohols with a γ-silyl group (3) generally undergo a simple carbonium ion rearrangement in acid giving a single alkene product (4) with loss of the silyl group.
