Synthesis of gem-dihaloenynes and butatrienes from gem-dihalovinyl derivatives
摘要:
gem-Dihaloenynes were synthesized in high yields from 1,1,4,4-tetrahalo-1,3-butadienes through the Fritsch-Buttenberg-Wiechell (FBW) rearrangement mediated by an organolithium compound. Butatriene derivatives could be obtained efficiently via an organolithium-mediated reaction of o-halo-(2,2-dihalovinyl)benzenes. (C) 2012 Elsevier Ltd. All rights reserved.
Elimination of β-Thioalkoxy Alcohols under Mitsunobu Conditions. A New Synthesis of Conjugated Enynes from Propargylic Dithioacetals
作者:Chih-Wei Chen、Tien-Yau Luh
DOI:10.1021/jo8013885
日期:2008.11.7
Treatment of propargylic dithiolanes 1 with (n)BuLi followed by a carbonyl electrophile yields the corresponding homopropargylic alcohol 3. Upon treatment with 2 equiv of PPh3 and DIAD, elimination of SR and OH moieties from 3 affords the corresponding olefins 4 in moderate to good yield. The reaction can be considered an alternative of McMurry coupling of two different carbonyl equivalents.