Synthesis and characterisation of porphyrazinoctamine derivatives: X-ray crystallographic studies of [2,3,7,8,12,13,17,18-octakis(dibenzylamino)- porphyrazinato]magnesium(II) and {2,3,7,8,12,13,17,18-octakis[allyl(benzyl)amino]- porphyrazinato} nickel(II)

2,3-Bis(dibenzylamino)- and 2,3-bis[allyl(benzyl)amino]-2Z-butene-1,4-dinitriles are macrocyclised by reaction with magnesium propoxide in propanol to provide the corresponding (porphyrazinato)magnesium(II) derivatives, the structures of which are confirmed by X-ray crystallographic studies of the title magnesium and nickel(II) complexes; cyclisation of alternative diaminomaleonitrile derivatives gives the corresponding porphyrazinoctamines.