Organosodium compounds coupling

The mechanism of the Wurtz coupling is not well understood, and the currently accepted mechanism involves two steps 1) formation of a carbanionic organosodium compound via metal-halogen exchange and 2) the displacement of the halide ion by the organosodium species in an Sn2 reaction. Alternatively, a radical process can also be envisioned, although to date there has been no experimental evidence to support this assumption. 

Aryl ethers can be cleaved by metallic sodium with the formation of the sodium salt of a phenol. A number of such reactions have been studied qualitatively, but the nature of the other products of these reactions has not been established in a sufficient number of cases to demonstrate the mechanism of the reaction (28). In some cases, the isolation of coupling products has suggested that the displaced group is a free radical in other cases it appears that an organosodium compound was at least a transitory intermediate. 

A variety of organometallic compoundshave been used to couple with alkyl halides. " Organosodium and organopotassium compounds are more reactive than Grignard reagents and couple even with less reactive halides. Organolithium... 

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