Alkyl cyanides preparation

Aliphatic nitriles (or alkyl cyanides) can be prepared by the following methods ... 

The large rate enhancements observed for bimolecular nucleophilic substitutions m polai aprotic solvents are used to advantage m synthetic applications An example can be seen m the preparation of alkyl cyanides (mtiiles) by the reaction of sodium cyanide with alkyl halides... 

Primary and secondary alkyl halides may be converted to the next higher carboxylic acid by a two step synthetic sequence involving the preparation and hydrolysis of nitriles Nitnles also known as alkyl cyanides are prepared by nucleophilic substitution... 

Nitrile groups m cyanohydrins are hydrolyzed under conditions similar to those of alkyl cyanides Cyanohydrin formation followed by hydrolysis provides a route to the preparation of a hydroxy carboxylic acids... 

Hydrocarbon Gngnard reagents give the alkyl cyanides, whereas perfluo-rinated Grignard reagents produce the sulfides This reaction is useful for the preparation of alkyl perfluoroalkyl sulfides to the exclusion of di and polysulfides, which are produced by other methods... 

A common method for the preparation of alkyl cyanide 2 is the treatment of corresponding alkyl halides 1 with cyanide. The corresponding reaction with aromatic substrates is called the Rosenmund-von-Braun reaction. 

Vinylic copper reagents react with CICN to give vinyl cyanides, though BrCN and ICN give the vinylic halide instead." Vinylic cyanides have also been prepared by the reaction between vinylic lithium compounds and phenyl cyanate PhOCN." Alkyl cyanides (RCN) have been prepared, in varying yields, by treatment of sodium trialkylcyanoborates with NaCN and lead tetraacetate." Vinyl bromides reacted with KCN, in the presence of a nickel complex and zinc metal to give the vinyl nitrile. Vinyl triflates react with LiCN, in the presence of a palladium catalyst, to give the vinyl nitrile." ... 

Acetone cyanhydrin has been used as a convenient source of cyanide ion for the preparation of alkyl cyanides (6.1.1.E) [21]. Moderate yields (50-77%) have been achieved using tetra-n-butylammonium cyanide or hydroxide as the base. 

Reaction conditions which are particularly applicable to aromatic nitriles involve the use of an aqueous solution of sodium hydroxide containing hydrogen peroxide, but alkyl cyanides do not always give good results the method is illustrated by the preparation of toluamide (Expt 6.167). 

Alkyl cyanides in general are smoothly reduced to primary amines (giving a product having one carbon atom more than the alkyl halide starting material) by the action of sodium and ethanol (e.g. the preparation of pentylamine, Expt... 

In a variation of the Gatterman reaction an alkyl cyanide RCN is used in place of HCN as a useful way of preparing ketones from reactive aromatic species that do not react well under Friedel-Crafts conditions. The electrophile involved is effectively R—C NH+, although, perhaps, the imino chloride, R(C NH)C1, the analogue of an acyl chloride, RCOCl, is also involved. As in the Gatterman reaction, the imine is an intermediate. 

Complex 376 can be prepared from enantiomerically pure rhenium precursor 381. The former can be deprotonated at low temperatures initiating the [2,3]-sigmatropic rearrangement to diastereomerically pure homoallylic sulfide complex 377. After S-alkylation, cyanide treatment releases the S ligand as product 379. As an extension of this work the authors showed that iron and ruthenium complexes can be used, too [219]. 

Until the 1920s, a-amino acids 5 were synthesized by the hydrolysis of the a-anoino-sub-stituted alkyl cyanides but subsequently the a-amino acids were produced industrially by hydrolyzing the hydantoin derivatives 4 (Scheme 1). The latter can be prepared by the Bucherer-Bergs four-component reaction (BB-4CR),f an MCR of type II that forms 4 from carbon dioxide and the three components of the S-3CR. The a-amino acids thus prepared are obtained in much higher yields than by the S-3CR. 

This is a general method for preparing amines, and affords another proof that carbon is linked to carbon in the alkyl cyanides. 

Alkyl phosphates, preparation, 16, 9 Alkyl sulfates, preparation, 19, 27 Alkyl sulfides, preparation, 15, 72 Alkyl sulfites, preparation, 19, 29 Ai-AlkyW -toluidines, 18,42 Allanioin, 13,1 Allyl alcohol, 10, 107 16, 85 Allylamine, 18, 5 Allyl cyanide, 16, 85 Allyl isothiocyanate, 18, 5 Alumina, 17, 27... 

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