Co5C and Co4C carbido carbonyl clusters stabilized by [AuPPh3]+ fragments

The synthesis and structural characterization of [Co5C(CO)(11)(AuPPh3)(3)], 1-A and 1-B, [Co5C(CO)(11) (AuPPh3)(2)], 2, [Co5C(CO)(10)(PPh3)(2)(AuPPh3)], 3, [Co5C(CO)(12)(AuPPh3)], 4, [Co5C(CO)(11)(PPh3)(AuPPh3)], 5, and [Co4C(CO)(10)(AuPPh3)(2)], 6, is herein reported. Compounds 1-6 have been obtained whilst studying the reactivity of [Co6C(CO)(15)](2-) with [Au(PPh3)Cl] under different experimental conditions, even if better alternative syntheses have been, then, found for some of these new clusters. 1-6 contain the electron precise [Co5C(CO)(12)](-), [Co5C(CO)(11)](3-) and [Co4C(CO)(10)](2) clusters, or their PPh3 derivatives, stabilized by [AuPPh3](+) fragments. Two different isomers of 1, i.e., 1-A and 1-B, have been found in the solid state due to solvation effects and weak d(10)-d(10) Au(I)...Au(I) aurophilic interactions. 1-A and 4 have been previously described in the literature.