Photochemical Wolff Rearrangement Initiated Generation and Subsequent α-Chlorination of C1 Ammonium Enolates

Org Lett. 2023 May 5;25(17):3126-3130. doi: 10.1021/acs.orglett.3c00986. Epub 2023 Apr 25.

Abstract

The enantioselective synthesis of α-chlorinated carboxylic acid esters with er up to 99:1 and yields up to 82% was achieved via a one-pot multistep protocol starting from α-diazoketones. This process proceeds via a photochemical Wolff rearrangement, trapping of the generated ketene with a chiral Lewis base catalyst, subsequent enantioselective α-chlorination, and a final nucleophilic displacement of the bound catalyst. The obtained products were successfully utilized for stereospecific nucleophilic displacement reactions with N- and S-nucleophiles.