5,10,15,20-Tetra-2-furylporphyrin

Abstract

Molecules of the title macrocycle, C36H22N4O4, are located on an inversion center. The porphyrin ring shows a wave-like conformation with adjacent pyrrole rings tilted above the porphyrin plane and the interporphyrin distance is 3.584 (3) Å. The dihedral angles between the meso-furyl groups and the porphyrin plane are 38.87 (7) and 48.29 (7)°; these are much smaller than those observed for meso-tetraphenylporphyrin, indicating that the meso-furyl groups are more inclined towards the porphyrin plane. The decrease in the dihedral angle is due to the presence of intramolecular hydroden bonding between the meso-fury O atom and the β-pyrrole CH group. Intramolecular N—H...N hydrogen bonds are also present.