Cross-coupling reaction of cyclic quaternary ammonium salts with arylzinc reagents, arylboron reagents, and silylboronates†

The nickel-catalyzed reaction of benzocyclic quaternary ammonium salts with arylzinc reagents or arylboron reagents affords amino-retentive arylation products in 40%–95% yields. This protocol is suitable for various substituted benzocyclic quaternary ammonium salts and arylzinc or arylboron reagents. The transition-metal-free reaction of benzocyclic quaternary ammonium salts with PhMe₂SiBpin in the presence of LiO^tBu leads to amino-retentive silylation products. 2-, 3-, 4-, 6-, and 7-position substituted 1,1-dimethyl-1,2,3,4-tetrahydroquinolin-1-ium triflates and 1,1-dimethyl-2,3,4,5-tetrahydro-1H-benzo[b]azepin-1-ium triflate can be silylated in 34%–95% yields.