Cyclization of 1,<i>n</i>-Enynes Initiated by the Addition Reaction of <i>gem</i>-Dichromiomethane Reagents to Alkynes
作者:Masahito Murai、Ryuji Taniguchi、Kazuhiko Takai
DOI:10.1021/acs.orglett.0c01304
日期:2020.5.15
Treatment of 1,n-enynes with gem-dichromiomethane species prepared in situ from 1,1-diiodomethanes and CrCl2 gave alkenylbicycloalkanes. Alkenylcarbene species, which was generated via [2 + 2] cycloaddition with a triple bond, were intercepted by intramolecular cyclopropanation of a pendant double bond, and alkene metathesis did not proceed. This is a very rare example of transformation of alkynyl
Regiodivergent Carbene/Alkyne Metathesis in Chromium-Mediated Coupling and Cyclization with 1,6-Enynes
作者:Masahito Murai、Ryuji Taniguchi、Kazuhiko Takai
DOI:10.1246/bcsj.20210305
日期:2021.12.15
Regiodivergent carbene/alkynemetathesis for the selective synthesis of 2-alkylidenebicyclo[4.1.0]heptanes and 1-alkenylbicyclo[3.1.0]hexanes from common 1,6-enynes precursors was demonstrated. The cyclization mode could be switched by simple addition of diamine ligands to control the relative orientation of the approaching chromium Schrock carbene equivalents generated in situ from gem-dichromiomethanes