CRYSTAL-STRUCTURE OF )-OXO-ESAKIS(MU(2)-ACETATE)TRIAQUATRICHROMIUM(III) 2,6-DIHYDROXYBENZOATE DIHYDRATE

The compound [Cr-2(mu(2)-CH3COO)(6)(mu(3)-O)(H2O)(3)]DHB . 2H(2)O (DHB = 2,6-dihydroxybenzoate(-1)), as characterized by single crystal X-ra y analysis and spectroscopy, is described. The compound crystallizes i n the monoclinic space group Cc with a = 14.122(3), b = 15.137(4), c = 14.952(3) Angstrom, beta = 99.70(3)degrees, Z = 4. The structure of t he complex consists of the trimetallic cage common to 'basic' acetates of Cr(III), Fe(III) and Rh(III), where three metal ions lie at the co mers of a nearly equilateral triangle of side similar to 3.3 Angstrom, the center being occupied by a triply-bridging oxygen. The chromium c oordination is compared with those found in related complexes. The DHB anion is anchored to the trichromium moiety through bonding between t he carboxylate group and a metal-bound water molecule.