7-COORDINATION IN SOME MONONUCLEAR AND BINUCLEAR IRON(3) COMPLEXES CONTAINING A PENTADENTATE MACROCYCLIC RING

The preparations and properties of two novel series of seven-coordinate iron(III) complexes are reported. In both series, the stereochemistry involves pentagonal-bipyramidal coordination about the iron atom with the five donor atoms of a pentadentate macrocycle occupying a single plane and monodentate groups above and below that plane. The macrocycle is 2,13-dimethyl-3,6,9,12,18-pentaazabicyclo[12.3.1]octadeca-l(18),2,12,14,16-pentaene (ligand B). Monomeric FeBX2Y compounds are formed for X = Cl, Br, I, or NCS and Y = ClO4, BF4, or NCS. The species are high spin and act as uni-univalent electrolytes in nitromethane. Dimeric [XBFe-O-FeBX] Y2 (X = ClO4 or NCS; Y = ClO4) involves spin-spin coupling across the Fe-O-Fe linkage. © 1969, American Chemical Society. All rights reserved.