Alkyl halides Compounds with halogen nucleophilic

A key step in the reaction mechanism appears to be nucleophilic attack on the alkyl halide by the negatively charged copper atom but the details of the mechanism are not well understood Indeed there is probably more than one mechanism by which cuprates react with organic halogen compounds Vinyl halides and aryl halides are known to be very unreactive toward nucleophilic attack yet react with lithium dialkylcuprates... 

The polarity of carbon-halogen bond of alkyl halides is responsible for their nucleophilic substitution, elimination and their reaction with metal atoms to form organometallic compounds. Nucleophilic substitution reactions are categorised into and on the basis of their kinetic properties. Chirality has a profound role in understanding the reaction mechanisms of Sj l and Sj 2 reactions. Sj 2 reactions of chiral all l halides are characterised by the inversion of configuration while Sj l reactions are characterised by racemisation. 

When CH3Li or n-BuLi is used in halogen-metal exchange, a rather electrophilic MeX or n-BuX is obtained as a by-product. The alkyl halide can undergo S 2 substitution with the organolithium compound as nucleophile to give the nucleophilic aromatic substitution product. However, Sn2 reactions of organolithium compounds with alkyl... 

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