Cobalt complexes directional nature

Subsequent reactions of the methyl radicals produce the stable organic products ethane and methane. Schrauzer et al. [81] have shown that the ratio of ethane to methane is sensitive to the nature of both the equatorial and axial ligands. In addition, studies of methylcobalt photolyses in DjO showed that methane arises via two competing processes direct abstraction of a hydrogen atom from the equatorial ligand system (Eqn. 46, in which Co (Chelate)L represents the cobalt complex minus one hydrogen atom)... 

The high selectivity of the reaction of cobalt-carbene complexes with alkynes for furan products was taken advantage of in the synthesis of bovolide, a natural flavor constituent of butter. The carbene complex (230) was prepared in two steps from n-pentanal and was treated with 3 equiv. of 2-butyne. The crude reaction mixture, which presumably contained the furan (231), was treated directly with 3 equiv. of trimethylsilyl iodide to give bovolide in - 50% yield from carbene complex (230). 

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