Absence of the Thorpe-Ingold effect by gem-diphenyl groups in ring-closing enyne metathesis

[摘要] In tandem ring-closing metathesis of alkynyl silaketals containing two different tethered olefins, the gem-dimethyl group showed the expected Thorpe-Ingold effect, thereby giving good level of group selectivity. Unexpectedly, however, the corresponding gem-diphenyl group did not show any Thorpe-Ingold effect for the ring-closure reaction. (c) 2007 Elsevier Ltd. All rights reserved.

[发布日期] 2007-11-05

[关键词] thorpe;ingold effect;cyclization;enyne metathesis;ring-closing metathesis;silicon