A highly enantioselectivearylation of 3-carboxamide oxoindoles with quinone monoimines is described. Various 3-aryl-3-carboxamide oxindoles with an all-carbon quaternary center were obtained in moderate to good yields (up to 99%) with moderate to good enantioselectivities (up to 98%) in the presence of a bifunctional thiourea-tertiary amine catalyst. The absolute configuration of one product was determined
A formal [3 + 3] cyclization reaction of 2-indolylmethanols with quinones was realized to furnish indole-fused scaffolds in moderate to excellent yields. This protocol was proceeded smoothly under acid condition, with high high yields and broad substrate scope.
Catalytic chemoselective [3+3] cycloadditions of azomethine ylides with quinone monoimides leading to the construction of a dihydrobenzoxazine scaffold
作者:Cong-Shuai Wang、Ren-Yi Zhu、Yu-Chen Zhang、Feng Shi
DOI:10.1039/c5cc03341a
日期:——
A chemoselective [3+3] cycloaddition of in situ generated azomethine ylides with quinone monoimides has been established, which efficiently led to the construction of dihydrobenzoxazine frameworks with biological relevance.
The first enantioselective dearomative [3+2] annulation of 5-amino-isoxazoles with quinonemonoimines was realized using a chiralphosphoricacid as catalyst. Various novel (bridged) isoxazoline fused dihydrobenzofurans bearing two continuous quaternary stereocenters were achieved in moderate to good yields (up to 94%) with moderate to good enantioselectivities (up to 98% ee). The absolute configurations
In the presence of a catalytic amount of trityl perchlorate, 1,4-benzoquinone, quinonemonoimides, or imidoquinones react with silyl enol ethers to produce the corresponding benzofuran or indole derivatives in high yields via the corresponding Michael adducts.