title: Catalytic Enantioselective Synthesis of 3,4-Unsubstituted Thiochromenes through Sulfa-Michael/Julia-Kocienski Olefination Cascade Reaction.
abstract: A highly enantioselective cascade sulfa-Michael/Julia-Kocienski olefination reaction between 2-mercaptobenzaldehydes and β-substituted vinyl PT-sulfones has been realized for the synthesis of 3,4-unsubstituted 2H-thiochromenes. This reaction, catalyzed by diphenylprolinol TMS ether, proceeds through an aromatic iminium intermediate and furnishes a wide range of 2-substiuted 2H-thiochromenes with excellent enantioselectivities (up to 99:1 er).
authors.affiliation: Department of Organic Chemistry, Indian Institute of Science , Bangalore 560 012, India.
authors.forename: Amit Kumar
authors.identifier: 0000-0002-8792-4825
authors.initials: AK
authors.lastname: Simlandy
authors.affiliation: Department of Organic Chemistry, Indian Institute of Science , Bangalore 560 012, India.
authors.forename: Santanu
authors.identifier: 0000-0001-9651-6228
authors.initials: S
authors.lastname: Mukherjee