STRUCTURE OF [LFE(MU-MOO4)3FEL].CH2CL2.H2O (L=1,4,7-TRIMETHYL-1,4,7-TRIAZACYCLONONANE)

Tri-mu-molybdato(2-)-bis[(1,4,7-trimethyl-1,4,7-triazacyclononane)iron(III)]-dichloromethane-water (1/1/1), [Fe2(MoO4)3(C9H21N3)2].CH2Cl2.H2O, M(r) = 1037.0, orthorhombic, Pbca, a = 15.239 (2), b = 16.376 (3), c = 28.964 (4) angstrom, V = 7227.9 (17) angstrom 3, D(x) = 1.91 g cm-3, Z = 8, lambda(Mo K-alpha) = 0.71073 angstrom, mu = 19.8 cm-1, F(000) = 4144, T = 293 K, R = 0.047, wR = 0.051 for 2457 observed reflections. The structure consists of a tri-mu-molybdato-diiron(III) molecular cluster, similar to that of [LFe(CrO4)3-FeL].H2O (L = 1,4,7-trimethyl-1,4,7-triazacyclononane) [Chaudhuri, Winter, Wieghardt, Gehring, Haase, Nuber & Weiss (1988). Inorg. Chem. 27, 1564-1569]. The synthesis from acetonitrile affords a convenient preparation of crystalline complex and avoids the use of perchlorate salts. The complex provides an unusual example of an early-transition-metal polyoxoanion which is neutral, rather than anionic as is the case with the vast majority of polyoxometalate species [Pope (1983). Heteropoly and Isopoly Oxometalates. Berlin: Springer-Verlag].