1373121-39-1Relevant articles and documents
Enantioselective synthesis of dihydropyrazoles by formal [4+1] cycloaddition of in situ-derived azoalkenes and sulfur ylides
Chen, Jia-Rong,Dong, Wan-Rong,Candy, Mathieu,Pan, Fang-Fang,Joerres, Manuel,Bolm, Carsten
, p. 6924 - 6927 (2012/06/15)
An unprecedented strategy to access highly enantioenriched dihydropyrazoles is described. It involves formal [4+1] cycloadditions of in situ-derived azoalkenes and sulfur ylides catalyzed by a chiral copper/Tol-BINAP complex. A variety of synthetically and biologically important dihydropyrazoles have been obtained with high enantioselectivities (up to 97:3 er) in good yields (83-97%).