Cu-catalyzed asymmetric addition of alcohols to β,γ-alkynyl-α-imino esters for the construction of linear chiral N,O-ketals.

ABSTRACT: N,O-acetals are part of many synthetic intermediates and important skeletons of numerous natural products and pharmaceutical drugs. The most straightforward method of the synthesis of N,O-acetals is the enantioselective addition of O-nucleophiles to imines. However, using this method for the synthesis of linear chiral N,O-ketals still remains challenging due to the instability of raw materials under acidic or basic conditions. Herein, we developed a Cu-catalyzed asymmetric addition of alcohols to β,γ-alkynyl-α-imino esters under mild conditions, providing the corresponding linear chiral N,O-ketals with up to 96% ee. The method tolerates some variation in the β,γ-alkynyl-α-imino ester and alcohol scope, including some glucose and natural amino acid derivatives. Computational results indicat

SUBMITTER: Sheng C 

PROVIDER: S-EPMC8776757 | biostudies-literature | 2022 Jan

REPOSITORIES: biostudies-literature