Diastereomeric Control in the Formation of Carbon−Cobalt Bonds in

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Inorg. Chem. 1997, 36, 1764-1771

Diastereomeric Control in the Formation of Carbon-Cobalt Bonds in Organocobalt Corrinoids: Reactions of Cobalt(II) Corrinoids with Organic Hydroperoxides1 Kenneth L. Brown,* Daqing Zhao, Shifa Cheng, and Xiang Zou Department of Chemistry, Ohio University, Athens, Ohio 45701 ReceiVed NoVember 27, 1996X

1,1-Dimethylpropyl hydroperoxide reacts with cobalt(II) cobinamide via a Fenton-like reaction to produce a mixture of the diastereomeric R- and β-ethylcobinamides (CH3CH2Cbi+’s, in which the organic ligand is in the “lower” or “upper” axial ligand position, respectively), the composition of which depends on the ratio of starting materials. When the hydroperoxide reagent is in excess,