One-pot synthesis of manganese(I) and rhenium(I) alkylcarbonato complexes,fac-(CO)(3)(dppp)MOC(O)OR. Possible trapping of intermediate diphosphine dimers, [(CO)(3)(dppp)M](2)

The reactions of Mn-2(CO)(10) and Re-2(CO)(10) With dppp, where, dppp is 1, 3-bis(diphenylphosphino)propane, in primary alcohols, yielded the correspon ding hydrides, fac-(CO)(3)(dppp)MH under argon atmosphere. However. similar reactions of the metal carbonyls with diphosphines in alcohols in the pres ence of air or carbon dioxide afforded one equivalent of the corresponding hydrides, fac-(CO)(3)(dppp)MH and one equivalent of the alkylcarbonato comp lexes, fac-(CO)(3),(dppp)MOC(O)OCH2R. The rhenium propylcarbonato complex, fac-(CO)(3)(dppp)ReOC(O)OCH2CH2CH3 is very stable and has been characterize d by X-ray crystal structure determination. The manganese-analog, fac-(CO)( 3)(dppp)MnOC(O)OCH2CH2CH3 is moisture-sensitive and converted slowly to the known carbonato-bridged complex, (CO)(3)(dppp)MnOC(O)OMn(dppp)(CO)(3). (C) 2001 Elsevier Science B.V. All rights reserved.