摘要

A metal-free oxidative cross-dehydrogenative coupling of N-aryl tetrahydroisoquinolines and 2-methylazaarenes in water under mild conditions has been developed. 4-Acetylamino-2,2,6,6-tetramethylpiperidine-1-oxoammonium tetrafluoroborate was employed as a mild oxidant that can be recovered and reused directly. The reaction proceeds through formation of an iminium ion in situ followed by condensation with various nucleophiles, providing the desired products in moderate to good yields.