Development of Axially Chiral Styrene-Type Carboxylic Acid Ligands via Palladium-Catalyzed Asymmetric C-H Alkynylation.

A weakly coordinated carboxylate-directed palladium-catalyzed atroposelective C-H alkynylation method for the development of novel axially chiral styrene-type carboxylic acids is disclosed. This transformation exhibits good yields (up to 85%), excellent enantiocontrol (up to 99% ee), and mild conditions. Notably, the synthetic utility of the resulting alkynyl carboxylic acid derivatives was demonstrated by various derivatizations as well as their potential as chiral ligands in asymmetric C-H activations.