Photochemical Wolff Rearrangement Initiated Generation and Subsequent α-Chlorination of C1 Ammonium Enolates
David Weinzierl, Magdalena Piringer, Paul Zebrowski, Lotte Stockhammer, Mario Waser
Abstract
High Resolution Image Download MS PowerPoint Slide 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.
Topics & Concepts
ChemistryWolff rearrangementNucleophileKeteneEnantioselective synthesisLewis acids and basesCatalysisStereospecificityMedicinal chemistryPhotochemistryOrganic chemistryCombinatorial chemistryCyclopropane Reaction MechanismsCatalytic C–H Functionalization MethodsOxidative Organic Chemistry Reactions