Enantioselective intramolecular cyclization of alkynyl esters catalyzed by a chiral Brnsted base

An enantioselective intramolecular cyclization reaction of alkynyl esters was developed, which employs a Brnsted base catalyst generated in situ from a chiral Schiff base and t -BuOK. This reaction is a rare example of the enantioselective intramolecular addition of simple ester enolates to alkynes under Brnsted base catalysis. An enantioselective intramolecular cyclization reaction of alkynyl esters was developed, which employs a Brnsted base catalyst generated in situ from a chiral Schiff base and t -BuOK.