Corroles Cannot Ruffle

X-ray structures of Co-III[(CF3)(3)Cor](PPh3) [(CF3)(3)Cor = meso-tris(trifluoromethyl)corrolato] and Cu[(CF3)(4)Por] [(CF3)(4)Por = meso-tetralcis(trifluoromethyl)porphyrinato] revealed planar and highly ruffled macrocycle conformations, respectively, in line with analogous observations for a handful of other meso-perfluoroalkylated porphyrins and corroles reported in the literature. To gain insights into the difference in conformational behavior, we evaluated DFT (BP86-D/TZP) ruffling potentials for a variety of corrole complexes, as well as their porphyrin analogues. The calculations led us to conclude that corrole derivatives, in essence, cannot ruffle.