Binuclear fluoro-bridged zinc and cadmium complexes of a schiff base expanded porphyrin: fluoride abstraction from the tetrafluoroborate anion.

Reactions of the Schiff base oligopyrrolic octaazamacrocycle 1 with BF4- salts of divalent zinc and cadmium result in fluoride anion abstraction and the formation of difluoride-bridged metal complexes. X-ray diffraction analyses provide support for the notion that hydrogen-bonding interactions, involving the N-H groups of the macrocycle and the coordinated fluoride ions, play an important role in stabilizing these new complexes.