Chiral phosphoric acid-catalyzed reaction between C-alkynyl imine precursor and thiol: Access to highly enantioenriched alkynyl isoindolinones with N,S-ketal framework

An enantioselective reaction of cyclic C-alkynyl imine precursor with thiols catalyzed by (R)-H8-TRIP has been described. A broad range of alkynyl isoindolinones possessing a single chiral quaternary center and an N,S-ketal framework were synthesized in high yields (up to 99%) and excellent enantioselectivity (up to 99% ee). The practicality of the methodology was depicted by a gram scale synthesis and interesting synthetic transformation of products.(c) 2022 Elsevier Ltd. All rights reserved.