Low-coordinate transition-metal complexes of a carbon-substituted hemiporphyrazine

Inorg Chem. 2007 Aug 6;46(16):6239-41. doi: 10.1021/ic7011099. Epub 2007 Jul 4.

Abstract

The metallation of the core-modified phthalocyanine analogue dicarbahemiporphyrazine with manganese, iron, and cobalt results in the formation of low-coordinate metal(II) complexes. All three compounds are produced by the reaction of metal carbonyls with the free base macrocycle. As in many other carbaporphyrinoids, the internal C-H bonds remain intact upon metallation, resulting in the formation of two long-range agostic-type interactions. Each metal can thus be considered as a three-coordinate ion, where two inner isoindolene nitrogens and a single axial pyridine are bound to the metal. The manganese and cobalt complexes, Mn(dchp)py and Co(dchp)py, are nearly isostructural, but the iron complex, Fe(dchpH2)py, exhibits a reduction at an iminic double bond upon metallation.