Dual Roles of Sulfonyl Hydrazides: A Three-Component Reaction To Construct Fully Substituted Pyrazoles Using TBAI/TBHP
† Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, P. R. China
‡ Key Laboratory of Advanced Catalytic Materials and Technology, Changzhou University, Changzhou 213164, P. R. China
Org. Lett. 2014, 16, 3312–3315
A mild and rapid approach has been developed for the construction of fully substituted pyrazoles using TBAI as a catalyst and TBHP as an oxidant, in which tosylhydrazide functions as the ring component and sulfonyl precursor. This protocol features a wide substrate scope with a broad range of functional group tolerance, utilizes easily available starting materials, can be scaled-up, and is operationally simple.