The reaction of samarium(II) with manganese carbonyl:: unexpected conversion of CO to formate.: X-ray crystal structures of [Sm(TpMe2)2]Mn(CO)5 and {[Sm(TpMe2)2]2(μ-HCO2)}Mn(CO)5 (TpMe2 = HB(3,5-dimethylpyrazolyl)

The reaction of [Sm(Tp(Me2))(2)] with Mn2CO10 results in the reductive cleavage of the Mn-Mn bond and the formation of the salt [Sm(Tp(Me2))(2)]Mn(CO)(5) which has been characterized by X-ray diffraction (Tp(Me2) = HB(3,5-dimethylpyrazolyl)(3)). In addition a second product, [(Tp(Me2))(2)Sm(mu-O2CH)Sm(Tp(Me2))(2)]Mn(CO)(5), was isolated and characterized crystallographically. Two mechanisms for the formation of this complex are proposed. (C) 2002 Elsevier Science B.V. All rights reserved.