Chiral Indoline‐2‐carboxylic Acid Enables Highly Enantioselective Catellani‐type Annulation with 4‐(Bromomethyl)cyclohexanone

Abstract

Chiral indoline-2-carboxylic acid has been identified to enable a highly enantioselective Catellani-type annulation of (hetero)aryl, alkenyl triflate and conjugated vinyl iodides with 4-(bromomethyl)cyclohexanone, directly assembling a diverse range of chiral all-carbon bridged ring systems. Control experiments and DFT calculations suggest that the coordinating orientation of the chiral amino acid to the arylpalladium-(II) center allows for high levels of stereochemical control.Scheme 1. Asymmetric Catellani-type reactions.