Methane from methylcobaloximes

The previously mentioned study of the base-catalyzed decomposition of ethyl-cobaloxime by Brown and Hessley [76] represents an interesting example of a base-catalyzed mode II cleavage. While the ethylene product of this reaction is undoubtedly formed via a mode I /8 elimination, the ethane product was originally thought to be formed by a mode III cleavage in analogy with the base-catalyzed formation of methane from methylcobaloxime (see Section 5.2 (c)). However,... 

Methyl radicals from methylcobaloxime and methylcobalamin abstract a hydrogen atom to give methane, or dimerize to form ethane. Often the radical scavenges hydrogen atoms and methyl groups originate from the ligands of the cobalt complexes . 

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