Crystal and molecular structure of di(pyridine)magnesium(II) octaethylporphyrinate

Abstract

The title compound crystallises in the triclinic space group P with unit-cell dimensions a= 10.607(3), b= 10.423(4), c= 9.957(4)A, α= 114.69(4), β= 90.56(3), and γ= 99.27(3)°. The structure was solved and refined by standard methods to R 0.036 for 2115 significant intensities measured by diffractometer. The unit cell contains one centrosymmetric molecule in which the magnesium atom is six-co-ordinated by the four nitrogen atoms from the porphyrinate ligand [Mg–N 2.064(2) and 2.072(2)A] and two pyridine nitrogen atoms with a unique distance of 2.389(2)A. This contrasts with most other Mg (tetrapyrrole) complexes which are either four- or five-co-ordinate species. The macrocycle shows small but significant deviations from planarity and has bond lengths and angles comparable with those of other metal loporphyrins.