A convenient method for the synthesis of 2-amino substituted aza-heterocycles from N,N′-disubstituted thioureas using TsCl/NaOH

p-Toluenesulfonyl chloride (TsCl)/NaOH has been introduced as reagent combination for the synthesis of 2-amino-oxa- or 2-amino-thiazolidines from N-(2-hydroxyethyl)-thioureas, but its general application in heterocycle synthesis has not been investigated. In this paper the convenient and efficient synthesis of a variety of 2-amino-substituted 1-aza 3-(aza, oxo or thio) heterocycles of different substitution and ring sizes is described. The application of polymer-supported TsCl facilitates work-up and renders the reaction conditions very suitable for parallel or robot synthesis.