Directly Pd(II)-Bridged Porphyrin Belts with Remarkable Curvatures

A β,β′-doubly 2,6-pyridylene-bridged porphyrin dimer and trimer were prepared by Suzuki−Miyaura coupling reactions and confirmed to have largely bent structures. These oligoporphyrins were readily metalated via meso-C−H bond activation with the assistance of the pyridyl nitrogen atoms to produce the corresponding Pd(II) complexes, which display even larger bent structures and larger TPA values at 800 nm.