1,3-Dipolar cycloaddition of diazoalkanes to racemic and optically active α-(diethoxyphosphoryl)vinyl p-tolyl sulfoxides: a new synthesis of 3-phosphorylpyrazoles and asymmetric synthesis of cyclopropanes
作者:Wanda H. Midura、Jerzy A. Krysiak、Marian Mikolajczyk
DOI:10.1016/s0040-4020(99)00943-6
日期:1999.12
Cycloaddition of diazomethane and ethyl diazoacetate to α-(diethoxyphosphoryl)vinyl p-tolyl sulfoxide 1a and its β-substituted analogues (Me, Ph) results in the formation of 3-phosphoryl-pyrazoles in high yield. The reaction ofchiral (S)-(+)-1a with diphenyldiazomethane proceeds fully diastereoselectively to give the corresponding cyclopropane (+)-6a with the (Sc, SS) configuration determined by X-ray