摘要
Transition metal-catalyzed asymmetric transfer hydrogenation has been proven to be a powerful approach for the synthesis of chiral alcohols.Herein,a highly efficient and enantioselective transfer hydrogenation of dibenzoheptaheterocyclic ketones catalyzed by an arene-tethered TsDPEN-based Rh(ll)catalyst has been successfully developed,and a variety of dibenzoheptaheterocyclic ketones were reduced by a 1/1 mixture of formic acid and DBU(1,8-diazabicyclo[5.4.0]undec-7-ene)with high yields and enantioselectivities.With this method,the asymmetric reduction of 7,8-difluorodibenzo[b,e]thiepin-11(6H)-one has been realized,providing the key intermediate of baloxavir marboxil with>99% yield and>99% ee at a substrate/catalyst molar ratio of 1000.
基金
the Southern University of Science and Technology(start-up fund),Shenzhen Science and Technology Innovation Committee(No.KQTD20150717103157174)
Stable Support Plan Program of Shenzhen Natural Science Fund(Program Contract No.20200925161222002)
Key-Area Research and DevelopmentPt rogramofGuangdong Province((No.2020B010188001)
Innovative Team of Universities in Guangdong Province(No.2020KCXTD016)
National Natural Science Foundation of China(No.21991113)
the National Natural Science Foundation of China(No.22171129)
Shenzhen Science and Technology Innovation Committee(JCYJ20210324104202007)for financial support.