Synthesis and X-ray crystal structure of the dimolybdenum acetaldehyde complex [Mo<sub>2</sub>(η-MeCHO)(CO)<sub>4</sub>(η-C<sub>5</sub>H<sub>5</sub>)<sub>2</sub>]
作者:Harry Adams、Neil A. Bailey、J. Trevor Gauntlett、Mark J. Winter、Simon Woodward
DOI:10.1039/dt9910002217
日期:——
The reaction of [Mo(MeCHO)(CO)2(eta-C5H5)]- 1 with [C7H7][BF4] gives the three organometallics [Mo2(mu-eta-2-MeCHO)(CO)4(eta-C5H5)2] 2, [Mo(CO)3(eta-C5H5)}] and [Mo(CO)2(eta-3-C7H7)(eta-C5H5)], the first of which has been characterised by X-ray crystallography [monoclinic, space group P2(1)/c, a = 8.265(4), b = 15.191(3), c = 13.511(9) angstrom, beta = 97.89(5)-degrees, R 0.0362 for 2104 independent reflections for which l/sigma(l) > 3.0]. The molecule consists of two Mo(CO)2(eta-C5H5) groups linked by a Mo-Mo bond [2.9670(8) angstrom] and bridged by an acetaldehyde ligand (eta-2 through both C and O to one metal atom, sigma through the oxygen to the second metal). The same three products arise in the reaction of 1 with [Mo(CO)3(eta-C7H7)][BF4], together with [Mo(CO)3(eta-6-C7H7)}2]. Addition of LiBEt3H to [Mo2(mu-eta-2-MeCO)(CO)4(eta-C5H5)2]BF4 gives a high yield of 2, as does the reaction of HBF4.OEt2 with 1. The reactions of complex 1 with any of (CF3CO)2O, HC = CCH2Br, PhCH2Br, [M(CO)3(eta-C5H5)][BF4] (M = Mo or W), CH2Cl2, [Fe(eta-C5H5)2][PF6] and Fe2(SO4)3 lead to low yields of 2. The tungsten complex [W2(mu-eta-2-MeCHO)(CO)4(eta-C5H5)2] is produced in low yield in the reaction of Li[W(H)(COMe)(CO)2(eta-C5H5)] with HBF4.OEt2.