A NEW AND GENERAL-ROUTE TO N-UNSUBSTITUTED AZOMETHINE YLIDES FROM N-(SILYLMETHYL)THIOUREAS - CYCLOADDITION OF SYNTHETIC EQUIVALENTS OF NONSTABILIZED AMINONITRILE YLIDES

The S-methylation of N-(silylmethyl)thioureas followed by the desilyla tion generates N-unsubstituted azomethine ylides having both methylthi o and amino groups at the ylide carbon. These azomethine ylides react with electron-deficient olefins to give formal aminonitrile ylide cycl oadducts, novel 2-aminopyrrolines. Thus, the azomethine ylides can be synthetic equivalents of nonstabilized aminonitrile ylides which are o therwise relatively inaccessible.