Cobalt-Catalyzed Electrophilic Cyanation of Arylzinc Halides with N-Cyano-N-phenyl-p-methylbenzenesulfonamide (NCTS)

The cobalt-catalyzed cross-coupling of organozinc bromides with N-cyano-N-phenyl-p-methylbenzenesulfonamide (NCTS) is described. The same cobalt catalyst, cobalt(II) bromide, was used for both the synthesis of the organozinc species and the cross-coupling reaction. However in this case, a catalytic amount of zinc dust is necessary in the second step to release the low-valent cobalt. Under these mild conditions, moderate to excellent yields of different benzonitriles were obtained.