Synthesis, Table of Contents Synthesis 2016; 48(08): 1139-1146DOI: 10.1055/s-0035-1561334 paper © Georg Thieme Verlag Stuttgart · New YorkHighly Efficient Synthesis of N 1-Substituted 1H-Indazoles by DBU-Catalyzed Aza-Michael Reaction of Indazole with Enones Jingya Yang* a College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou 730070, P. R. of China Email: yangjy@nwnu.edu.cn , Yunfen Bao a College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou 730070, P. R. of China Email: yangjy@nwnu.edu.cn , Hongyan Zhou b College of Science, Gansu Agricultural University, Lanzhou 730070, P. R. of China , Tianyuan Li a College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou 730070, P. R. of China Email: yangjy@nwnu.edu.cn , Nana Li a College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou 730070, P. R. of China Email: yangjy@nwnu.edu.cn , Zheng Li a College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou 730070, P. R. of China Email: yangjy@nwnu.edu.cn› Author AffiliationsRecommend Article Abstract Buy Article All articles of this category Abstract 1H-Indazoles are important heterocycles as they are a substantial part in many drugs. Here, a DBU-catalyzed aza-Michael reaction of indazole with enones is described. A variety of aromatic and aliphatic enones are well tolerated and afford the corresponding N 1-substituted 1H-indazoles in high to excellent yields with exclusive N 1-regioselectivity. The use of a metal-free catalyst, good substrate tolerance, mild reaction conditions, and high atom economy make this procedure a direct and facile method for the preparation of N 1-substituted 1H-indazoles. 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