Methoxylation of the Re-Re bond in [Re2(CO)10] by methanol under ambient conditions

Abstract

Addition of 1,1′-bis(diphenylphosphino)ferrocene (dppf) to an 'activated mixture' containing [Re2(CO)10] and Me3NO·2H2O in thf-MeOH (2:1) in the molar ration 1.0:1.0:2.4 at 25 °C gives [Re2(μ-OMe)2(CO)6(μ-dppf)] in 34% yield. The molecular structure was determined by X-ray diffraction analysis: monoclinic, space group P21/n, a = 13.646(1), b = 18.440(2), c = 17.850(4) Å, β = 97.69(1) °, final R 0.030 for 3992 observations. It contains two tricarbonylrhenium(I) moieties bridged by dppf and two methoxo ligands. The cp-Fe-cp (cp = η-C5H5) axis of dppf makes a projection of 53.5° onto the Re-Re axis.