PREPARATION OF OXO-BRIDGED DINUCLEAR IRON(III) COMPLEXES WITH ONE OR 2 O,O'-BRIDGED OPTICALLY-ACTIVE AMINO-ACIDS

Amino-acid bridged diiron complexes, [Fe-2(mu-O)(mu-L)(2)(tacn)(2)](4) (tacn = 1,4,7-triazacyclononane; L = (S)-valine or (S)-proline) and [Fe-2(mu-O)(mu-L)(tpa)(2)]4(+) (tpa = tris(2 pyridylmethyl)amine; L = (S)valine, (S)-proline, or (S)-alanine) have been prepared. Crystal st ructures of the two tacn complexes were determined. Electronic absorpt ion spectra and redox properties of these complexes are similar to the corresponding mu-acetate complexes.