Heterobimetallic Ir-Sn catalysis: aza-Friedel-Crafts reaction of N-sulfonyl aldimines

The heterobimetallic complex [Ir(COD)(SnCl3)Cl(μ-Cl)]2 catalyzes the aza-Friedel-Crafts reaction of 1,3,5-trimethoxybenzene, as well as substituted indoles with N-sulfonyl aldimines leading to the formation of diarylamines and triarylmethanes in good yields. The symmetrical triarylmethanes were also obtained from diarylamines and suitable nucleophiles via simultaneous cleavage of sp3 C-N bond and elimination of 1,3,5-trimethoxybenzene.