SEARCH Articles Figures Tables Chromium complexes porphyrin complex, formation Complex formation porphyrin units Copper complexes porphyrin complex, formation Manganese porphyrins concerted intermediate formation Meso-5- porphyrin formation Nickel complexes with porphyrin, formation Porphyrin complex, formation Porphyrin iron monoxide, formation Porphyrin ring system formation Porphyrin, aromaticity formation from pyrrole Porphyrins Metal complex formation Porphyrins kinetic formation Ring formation porphyrins Synthetic porphyrins, dimer formation