Reactions of β‐Azolylenamines with Sulfonyl Azides as an Approach to N‐Unsubstituted 1,2,3‐Triazoles and Ethene‐1,2‐diamines

Abstract

AbstractThe reactions of β‐azolylenamines 1 with sulfonyl azides 2 in acetonitrile furnished 1H‐4‐(azol‐5‐yl)‐1,2,3‐triazoles 3 in yields of 52–93 %. β‐Benzoylenaminones and β‐nitroenamine of type 1 also reacted with tosyl azide to form the same type of products 3, proving the generality and efficiency of the method for the synthesis of N‐unsubstituted 1,2,3‐triazoles. On the other hand, the reactions of 3‐(1‐aryl‐1,2,3‐triazol‐5‐yl)enamines with tosyl azide in the absence of a solvent afforded a mixture of (E)‐1‐dimethylamino‐2‐tosylaminoethenes 5 and N,N‐dimethyl‐N′‐tosylformamidine 6 in yields of 40–50 and 20 %, respectively. The formation of a variety of compounds from the reactions of enamines 1 with sulfonyl azides 2 is rationalized by the various possible transformations of the intermediate 5‐dimethylamino‐1,2,3‐triazolines 7.