Brønsted Acid-Catalyzed Enantioselective and Para-Selective Addition of Phenols to 1-Alkynylnaphth-2-Ols

A chiral Br & oslash;nsted acid-catalyzed synthesis of axially chiral alkenes was developed via an enantioselective and para-selective Friedel-Crafts reaction between phenols and 1-alkynylnaphth-2-ols. This methodology features an efficient hydroarylation with high functional group tolerance, complete para-selectivity, excellent yields (up to 99%), and enantioselectivities (up to 94% ee) in the presence of a N-triflylphosphoramide catalyst. DFT calculations were performed to investigate para-selectivity and results indicate that both kinetics and thermodynamics parameters are more favorable compared to ortho-selectivity.