New mu-oxo octanuclear complexes of 3d elements stabilized by dialkylcarbamato ligands. Synthesis and X-ray crystal and molecular structures

Dell'Amico DB; Bradicich C; Calderazzo F; Guarini A; Labella L; Marchetti F; Tomei A

Inorganic Chemistry, Vol.41, No.11, 2814-2816, 2002

Dell'Amico DB, Bradicich C, Calderazzo F, Guarini A, Labella L, Marchetti F, Tomei A

The octanuclear aggregates M-8(mu(4)-O)(2)((O2CNPr2)-Pr-i)(12) [M = Mn(II) 1, Co(II) 2, Ni(II) 3] have been prepared in good yields by controlled hydrolysis of the corresponding metal carbamate precursors [M((O2CNPr2)-Pr-i)(2)](n). X-ray analysis has shown compounds 1-3 to be isostructural. The core of 2 contains two distorted {M4O} tetrahedra related by an inversion center. The hexanuclear carbamates M-6(O2CNEt2)(12) in toluene undergo a metal redistribution process with formation of the hexanuclear carbamates M-x'M6-x"(O2CNEt2)(12), M' = Co, M" = Mn, as evidenced by mass-spectrometric data. In the presence of moisture, the mixed octanuclear carbamates CoxMn6-x(MnO)(CoO)(O2CNEt2)(12) were promptly formed and detected by DCI/MS measurements. Mass spectral data of Co-8(mu(4)-O)(2)((O2CNPr2)-Pr-i)(12) are also reported.