title: Enantioselective tandem reaction over a site-isolated bifunctional catalyst.
abstract: Construction of a site-isolated heterogeneous catalyst to realize the compatibility of bimetallic complexes for a feasible tandem reaction is a significant challenge in heterogeneous asymmetric catalysis. Herein, taking advantage of yolk-shell-structured mesoporous silica, we assemble an active site-isolated bifunctional catalyst through assembly of organopalladium-functionality into silicate channels as an outer shell and chiral organoruthenium-functionality onto silicate yolk as an inner core, realizing the one-pot enantioselective tandem reaction from Pd-catalyzed Sonogashira coupling to Ru-catalyzed asymmetric transfer hydrogenation. As presented in this study, this tandem Sonogashira coupling-asymmetric transfer hydrogenation of haloacetophenones and arylacetylenes affords various chiral conjugated alkynols with high yields and up to 99% enantioselectivity. Moreover, a catalyst can also be recovered easily and recycled repeatedly, making it an interesting feature in a practical organic transformation.
authors.affiliation: Laboratory of Resource Chemistry of Ministry of Education, Shanghai Normal University, Shanghai 200234, China. ghliu@shnu.edu.cn.
authors.forename: Jianyou
authors.initials: J
authors.lastname: Xu
authors.forename: Tanyu
authors.initials: T
authors.lastname: Cheng
authors.forename: Kun
authors.initials: K
authors.lastname: Zhang
authors.forename: Ziyun
authors.initials: Z
authors.lastname: Wang
authors.forename: Guohua
authors.initials: G
authors.lastname: Liu