Alkyl halides, from alcohols nitrile alkylation with

Leadbeater NE, Torenius HM, Tye H (2003) Ionic liquids as reagents and solvents in conjunction with microwave heating rapid synthesis of alkyl halides from alcohols and nitriles from aryl halides. Tetrahedron 59 2253-2258... 

Moreover, the theories of the authors do not account for certain important features of their results that when the ratio [additive]/[AlCl3] is small, both the DP and the conductivity increase with increasing concentration of additive (alcohol, aldehyde, nitrile) and that with butyraldehyde the rate is markedly lower near the equivalence point where the DP is at a maximum, whereas in the alkyl halide-ethane mixtures both the rate and the DP went through a maximum at the same point. In our opinion the major part of these interesting results can be explained in the following terms, which coincide in part with the explanations given by the authors, but differ from theirs in two important respects. 

An ester is formed when a nitrile is heated with an alcohol in the presence of concentrated sulphuric acid, thus providing a two-step synthesis of an ester from an alkyl halide. Examples are to be found in Expt 5.152. The reaction proceeds by way of an intermediate imino-ester (7) which is not usually isolated, but may be if so required.163... 

From a historical perspective, the a-(dialkylamino)nitrile anions were the first acyl anion equivalents to undergo systematic investigation. More recent studies indicate that anions of a-(dialkylamino)nitriles derived from aliphatic, aromatic or heteroaromatic aldehydes intercept an array of electrophiles including alkyl halides, alkyl sulfonates, epoxides, aldehydes, ketones, acyl chlorides, chloroformates, unsaturated ketones, unsaturated esters and unsaturated nitriles. Aminonitriles are readily prepared and their anions are formed with a variety of bases such as sodium methoxide, KOH in alcohol, NaH, LDA, PhLi, sodium amide, 70% NaOH and potassium amide. Regeneration of the carbonyl group can be achieved... 

Various sulfuric and phosphoric acid esters have sometimes been used instead of alcohols as starting materials for the preparation of nitriles. Of more general importance are sulfonates, particularly from methane- or p-toluene-sulfonic acid, which react in an 5N2-type substitution with cyanide ions. The most common starting materials are, as described in Section 1.8.1.2.1, alkyl halides, and if their preparation creates problems, the use of sulfonates may be advantageous. The addition of crown ethers or the... 

Sodium superoxide in DMSO is a useful reagent for converting nitriles into amides. Isolated yields are above 70% for this reaction, which was unexpected as nitriles are inert to Na02 in other solvents. The mechanism is not completely understood. The Ritter-type synthesis of N-alkyl-amides from nitriles and alcohols can be improved by the addition of metal carbonyls to help stabilize the intermediate carbonium ions, and an alternative approach is to treat a nitrile with an alkyl halide and nitrosonium hexafluorophosphate. ... 

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