Regiocontrolled Palladium-Catalyzed Arylative Cyclizations of Alkynols

Tuning the reactivity
of arylpalladium intermediates enables control
of catalytic arylative 5-exo and 6-endo cyclizations of alkynols. The two modes of cyclizations represent
a rare example of controllable, regioselective difunctionalization
of alkynes. The cyclizations are useful in offering a divergent synthesis
of oxygen-containing heterocycles, which is of synthetic use for further
derivatization. Formal synthesis of an hNK-1 receptor antagonist also
showcases the utility of our arylative cyclization.