Rh(I)-Catalyzed [5 + 1] Cycloaddition of Vinylcyclopropanes and CO for the Synthesis of α,β- and β,γ-Cyclohexenones
摘要:
A cationic Rh(I)-catalyzed [5 + 1] cycloaddition of vinylcyclopropanes and CO has been developed, affording either beta,gamma-cyclohexenones as major products or alpha,beta-cyclohexenones exclusively, under different reaction conditions.
Rh(I)-Catalyzed [5 + 1] Cycloaddition of Vinylcyclopropanes and CO for the Synthesis of α,β- and β,γ-Cyclohexenones
摘要:
A cationic Rh(I)-catalyzed [5 + 1] cycloaddition of vinylcyclopropanes and CO has been developed, affording either beta,gamma-cyclohexenones as major products or alpha,beta-cyclohexenones exclusively, under different reaction conditions.
Convergent Synthesis of Dihydropyrans from Catalytic Three-Component Reactions of Vinylcyclopropanes, Diazoesters, and Diphenyl Sulfoxide
作者:Ya-Lin Zhang、Rui-Ting Guo、Heng Luo、Xin-Shen Liang、Xiao-Chen Wang
DOI:10.1021/acs.orglett.0c01992
日期:2020.7.17
three-component reaction of vinylcyclopropanes, diazoesters, and diphenyl sulfoxide has been developed. The reaction gives polysubstituted dihydropyrans as the reactionproducts. Mechanistic studies indicate that isomerization of vinylcyclopropanes gives conjugated dienes, which then undergo [4 + 2]-cycloaddition with vicinaltricarbonyl compounds generated by oxygen atom transfer from diphenyl sulfoxide
Catalytic [5 + 1]-Cycloadditions of Vinylcyclopropanes and Vinylidenes
作者:Conner M. Farley、Kohei Sasakura、You-Yun Zhou、Vibha V. Kanale、Christopher Uyeda
DOI:10.1021/jacs.0c00356
日期:2020.3.11
1]-cycloaddition between a vinylcyclopropane and a vinylidene to provide methylenecyclohexenes bearing all-meta relationships. Vinylidene equivalents are generated from 1,1-dichloroalkenes using Zn as a stoichiometric reductant. Experimental observations are consistent with a mechanism involving a cobaltacyclobutane formed from a [2 + 2]-cycloaddition between a cobalt vinylidene and a vinylcyclopropane.
A Fe2(CO)9-mediated [5+1] cycloaddition of vinylcyclopropanes (VCPs) and CO to α, β-cyclohexenones has been developed. The reaction can tolerate aryl and aliphatic groups at the α-position of VCPs, while VCP substrates with vinyl or alkynyl substitutions are not suitable ones. In addition, this reaction can also be used to synthesize bicyclic rings if an aryl group is attached to the vinyl moiety of