Bismuth porphyrin complexes: syntheses and structural studies

The synthesis of several new bismuth porphyrin complexes Bi(por)(X) containing the tpp or tpClpp (tpClpp = 5,10,15,20-tetra-pchlorophenylporphyrin) porphyrin ligand and anions X = NO3, Cl, Br, I are described. Molecular structures reported for Bi(tpClpp)(X) for X = Cl, Br show that the complexes crystallise as centrosymmetric dimers doubly bridged through Cl or Br. Bi(tpClpp)(NO3) crystallises as a less symmetric dimer in which one NO3 ligand bridges the two bismuth centres and the second NO3 ligand interacts with only one bismuth atom. In all three structures the bismuth atoms are significantly displaced from the porphyrin N4 planes and the Bi–halide or Bi–O distances are very long.