Redox noninnocent nature of acridine-based Pincer complexes of 3d metals and C–C bond formation

Acridine-based PNP pincer complexes have been previously utilized for several environmentally benign catalytic processes. In light of the recent growth in interest in base-metal catalysis, we report here the synthesis of acridine-PNP pincer complexes of Ni, Co, Fe, and Mn. We also report here the noninnocent redox nature of these complexes that results in the dimerization of pincer complexes by forming a C–C bond at the C9 position of the acridine ring.