Enantioselective (3+2)-Annulation of β-Keto Esters with Azoalkenes towards Bicyclic Dihydropyrroles via Cooperative Palladium and Brønsted Acid Catalysis
作者:Christoph Schneider、Till Friedmann、Daniel A. Mireles-Chávez、Frederik L. Walter
DOI:10.1055/a-2210-0973
日期:——
A cooperative catalytic process through palladium and Brønsted acid activation is developed for the conjugate addition of cyclic β-keto esters to azoalkenes directly followed by hemiaminal formation upon cyclization. This transformation is enabled by utilizing chiral Pd-aqua complexes as combined Brønsted acid–base catalysts. Thus, bicyclic and highly functionalized dihydropyrroles with two contiguous
开发了一种通过钯和布朗斯台德酸活化的协同催化工艺,用于将环状 β-酮酯共轭加成到偶氮烯烃上,然后在环化时直接形成半缩醛胺。这种转变是通过利用手性钯-水配合物作为组合的布朗斯台德酸碱催化剂来实现的。因此,具有两个连续的四级立构中心的双环和高度官能化的二氢吡咯作为单一非对映异构体以优异的产率形成,并且具有优异的对映选择性。