with exclusive regioselectivity and stereoselectivity. Functional application of such a resultant product by oxidative addition and epoxidation is also explored. Notably, the treatment of a pyrroline-fused N-glycoside (3a) with TMSOTf efficiently leads to an interesting unexpected C-nucleoside (9) via a TMSOTf-inducing ring opening/acetyl migration/ringclosingreaction sequence.
catalysis strategy for substituted 3-aminofurans synthesis has been developed. This transformation involves a tandem reaction sequence through aza-vinyl-rhodium(II) carbene O–H bond insertion, thermal propargyl-Claisen rearrangement and gold(I)-catalyzed intramolecular cyclization. More importantly, the current strategy employs simple feedstocks as starting materials, providing substituted 3-aminofurans in
Synthesis of 1-arylsulfonyl-1,2,3-triazoles from (Z)-arylvinyl bromides by sequential elimination–cycloaddition reaction
作者:Wensheng Zhang、Wenjing Xu
DOI:10.1007/s10593-016-1859-x
日期:2016.3
Efficient synthesis of 1-arylsulfonyl-1,2,3-triazoles from easily available (Z)-arylvinyl bromides is described. The sequential reaction involves elimination of HBr from (Z)-arylvinyl bromides promoted by KOH and copper-catalyzed (3+2) cycloaddition reaction between the alkyne intermediates and sulfonylazides.
A novel Rh(II)-catalyzed transannulation of 1-tosyl-1,2,3-triazoles with silyl or alkyl enolethers has been developed, which enables the facile synthesis of substituted pyrroles in a regiocontrollable manner. Moreover, the methodology could be extended to access 3-pyrrolin-2-one derivatives with silyl ketene acetals used as the reaction partner.