Cycloaddition of 1,4-Dimethyl-2,3-dimethylenehexahydropyrazine to Electron Deficient Alkenes
作者:Carina Sofia Kniep、Roland Boese、Reiner Sustmann
DOI:10.1016/s0040-4020(00)00340-9
日期:2000.6
The mechanism of cycloaddition of 1,4-dimethyl-2,3-dimethylenehexahydropyrazine to moderately and highly electrophilic alkenes is probed by stereochemical studies. Retention of configuration for the E/Z-isomeric alkenes fumaro- and maleonitrile and loss of stereospecificity for dimethyl dicyanofumarate and dimethyl dicyanomaleate show that the mechanism of cycloaddition (concerted or stepwise) depends