The reaction of Co2(CO)8 and Co4(CO)12 with the dipropargylamine [(HCCCMe2)2NMe].: Synthesis and crystal structure of the complex Co4(CO)10(μ-CO)[H2CCC(Me)2N(Me)C(Me2)C(μ4-C)]

The reaction of Co4(CO)12 with the dipropargylamine [(HCCCMe2)2NMe] (ligand A) leads to moderate yields of the title complex (complex 4). An X-ray analysis has shown that this tetranuclear complex is a ‘spiked’ (or metallo-ligated) triangular cluster containing one molecule of ligand A partially cyclized and coordinated to all four metal atoms. Complex 4 is the first tetracobalt cluster showing this type of structure which was previously found only for two M2Ni2 (M=Fe, Ru) isopropenylacetylene derivatives. Reaction pathways leading to the formation of complex 4 are discussed.