Nitriles reaction with organomagnesium compounds

The usual reactions of organomagnesium compounds with esters, amides and nitriles are those described in Sections 5.3, 6.2 and 6.3. However, factors such as steric hindrance and stability of leaving group may lead to reactions resulting in overall nucleophilic displacement. Most of them are of limited applicability (see Ref. [39] for examples involving carbamate), but two warrant coverage. 

The experimental conditions for the syntheses starting from acid chlorides of hydroxamic acids and from nitrile oxides are somewhat different. In the former case the other component of the reaction is organometallic, usually an organomagnesium derivative of an acetylene or, less frequently, a sodium enolate of a /8-diketone. Nitrile oxides condense directly with unsaturated compounds. 

Reactions of organomagnesium and organolithium compounds with nitriles normally proceed via initial addition to the carbon-nitrogen triple bond or via initial a-deprotonation ... 

The reaction of the rhodium(l) complex (CXLV) and organolithium or organomagnesium compounds produces the alkylrhodiums (CXLVI). Oxidative addition of an acid chloride to this intermediate, followed by reductive elimination, leads to unsymmetrical ketones in good yields. The alkyirhodium (CXLVI) does not react with aldehydes, esters, or nitriles. An additional benefit is that the starting rhodium complex (CXLV) is regenerated in reusable form in the last step (Hegedus et al., 1973, 1975a). Reaction of... 

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