Stabilization of a monomethyl orthomolybdate in the binding pocket of a dinuclear cobalt complex.
The ability of the dinuclear Co(II) complex [(L(Me))Co(II)2(mu-Cl)]+ [1; (L(Me))2- = 3,6,9,17,20,23-hexamethyl-3,6,9,17,20,23-hexaaza-29,30-dithiol-13,27-di-tert-butyltricyclo[23.3.1(11.15)]triaconta-1(28),11,13,15(30),25,26-hexaene] to bind tetrahedral oxoanions of the transition metal has been investigated. Two new complexes, [(L(Me))Co(II)2(mu-MoO4)] (2) and [(L(Me))Co(II)2(mu-MoO3(OMe))]2[Mo4O10(OMe)6] (3), were prepared by substitution reactions of 1 with (n-Bu4N)2MoO4 in MeCN or with MoO3 x 2 H2O/NEt3 in MeOH. Both compounds were characterized by X-ray crystallography. The dioctahedral complex 2 features a mu(1,3)-bridging MoO4(2-) unit, whereas the cation in 3 hosts an unprecedented mu(1,3)-MoO3(OMe)- motif, demonstrating that four-coordinate molybdate esters can be stabilized in the binding pocket of the bowl-shaped [(L(Me))Co(II)2]2+ complex. The results of IR, UV/vis, and cyclic voltammetry measurements are also reported.
Lozan
Vasile
V
Institut für Anorganische Chemie, Universität Leipzig, Johannisallee 29, 04103 Leipzig, Germany.
Kersting
Berthold
B