Corroles Cannot Ruffle

X-ray structures of CoIII[(CF3)3Cor](PPh3) [(CF3)3Cor = meso-tris(trifluoromethyl)corrolato] and Cu[(CF3)4Por] [(CF3)4Por = meso-tetrakis(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.