Nitriles with aromatic rings

Double bonds conjugated with aromatic rings and with carbonyl, carboxyl, nitrile and other functions are readily reduced by catalytic hydrogenation and by metals. These reductions are discussed in the appropriate sections aromatics, unsaturated aldehydes and ketones, unsaturated acids, their derivatives, etc. 

Acylation of aromatic rings with nitriles (Hoesch)... 

Interposition of an oxygen atom between the aromatic ring and the imidazoline-bearing side chain leads to a compound reported to show antidepressant activity. Its preparation begins with alkylation of phenol 125 with chloroacetonitrile to afford intermediate 126. Condensation of that nitrile with the... 

Nitrile oxides are widely used as dipoles in cycloaddition reactions for the synthesis of various heterocyclic rings. In order to promote reactions between nitrile oxides and less reactive carbon nucleophiles, Auricchio and coworkers studied the reactivity of nitrile oxides towards Lewis acids. They observed that, in the presence of gaseous BF3, nitrile oxides gave complexes in which the electrophilicity of the carbon atom was so enhanced that it could react with aromatic systems, stereoselectively yielding aryl oximes 65 and 66 (Scheme 35). ... 

Cyclizations with perfluoroacylating agents seem to be quite general for the synthesis of 5(2i7)-oxazolones with aromatic substituents directly bonded to the heterocyclic ring. For example, perfluoroacylation of a solution of an arylgly-cine containing a phosphorus trihalide affords 4-aryl-2-(perfluoroalkyl)-5(2//)-oxazolones (Table 7.1, Fig. 12) Similar results were obtained when amino nitriles were used as starting materials. ... 

Benzothiadiazines (158) are prepared by cyclization of the chlorohydrazones (212) on treatment with triethylamine (81JCS(Pl)2245). The reaction probably involves intramolecular nucleophilic attack by sulfur on a nitrile imine intermediate, since (212) does not cyclize on heating alone. Intramolecular aromatic sulfonation gives 1,2,4-benzothiadiazine 1,1-dioxides (214). Thus treatment of (213) with aluminum trichloride leads to cyclization with bond formation between sulfur and the aromatic ring (79JCS(P1)1043). 

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