Enantioselective Synthesis of Dihydropyrazoles by Formal [4+1] Cycloaddition of in Situ-Derived Azoalkenes and Sulfur Ylides
作者:Jia-Rong Chen、Wan-Rong Dong、Mathieu Candy、Fang-Fang Pan、Manuel Jörres、Carsten Bolm
DOI:10.1021/ja301196x
日期:2012.4.25
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%).
描述了一种前所未有的获得高度对映体富集的二氢吡唑的策略。它涉及由手性铜/Tol-BINAP配合物催化的原位衍生的偶氮烯烃和硫叶立德的正式[4+1]环加成。已经以高对映选择性(高达 97:3 er)以良好的产率(83-97%)获得了多种合成和生物学上重要的二氢吡唑。