Cyanopyridines alkali

Similar to last year s reported reaction <94H(37)1489> between 4-cyanopyridine, benzophenone, and metals to give diphenyl(4-pyridyl)carbinol, this year the reaction between 4-cyanopyridine, alkali metal, and ketones or aldehydes was reported to give 4-pyridinemethanols in good yield <95TL(36)7275>. 

Heterocyclic N-oxides such as pyridine, quinoline, or isoquinoline N-oxides can be converted into a mixture of 2- and some 4-cyanopyridines, 2- or 4-cyanoquino-lines, or 1-cyanoisoquinolines, in 40-70% yield, in a Reissert-Henze reaction, by activation of the N-oxide function by O-acylation [1] or O-alkylation [2, 3] followed by treatment with aqueous alkali metal cyanide in H2O or dioxane. 

The equilibrium between radical-anion and dimer for pyridine and quinoline has been examined in a number of aprotic solvents. Radical-anions of pyridine dimer-ise rapidly in liquid ammonia in tire presence of alkali metal ions [15] In hex-amethylphosphoramide with alkali metal counter ions, the monomer is detectable in an equlibrium concentration [16], The monomeric species can be stabilised by substituents and 2- or 4-cyanopyridines give radical-anions which persist in liquid ammonia while 3-cyanopyridine radical-anion dimerises with a rate constant of 2 x 10 [17], Quinoline radical-anion is stable in hexamelhylphosphoramide [16] but in liquid ammonia it dimerises irreversibly [18]. 

The fusion of alkali arylsulfonates with potassium cyanide forms aromatic nitriles by a replacement of the sulfo group. For the most part, the yields are low, although the reaction has been applied successfully in the preparation of naphthonitriles and cyanopyridines. Sometimes potassium ferrocyanide is substituted for the alkali cyanide with better results. Ten isomeric cyanonaphthalenesulfonates have been converted to the dinitriles by fusion with this reagent in yields ranging from 8% to 75%. Migration of the cyano group from the beta to the alpha position has been observed in the formation of these Compounds. ... 

Reaction of quaternary salt 226 with 4-melhylpiperidine gives rise to 4-(4-methylpiperidino)pyridine (277), which is a liquid, in contrast to the crystalline DMAP (228) and PPY (184) (83EUP74837). The reaction of 4-cyanopyridine (274) with acrylamide in the presence of HCI furnishes the crystalline quaternary salt 278, in quantitative yield, which is readily aminated with dimethylamine. Subsequent cleavage of the aminated quaternary salt by heating with strong alkali solution gives monomeric or... 

Benzonitrile acts in a similar way to form benzoic acid but requires sulfuric acid in the reacting mixture. Nicotinic acid amide (nicotinamide) has been prepared by the mild hydrolysis of 3-cyanopyridine, and acrylamide by the partial hydrolysis of acrylonitrile. Acrylonitrile may also be hydrolyzed to acrylic acid with mineral acids or with alkalies. Polyacrylonitrile is partially converted to the amide by nitric acid, and the nitrile oups of a number of polymers and copolymers have been hydrolyzed to amide and carboxylic acid groups to produce water-soluble polyelectrolytes. Isooyanides are stable toward alkalies but hydrolyze in the presence of acids to form an acid and an amine ... 

Replacement of the cyano group rather than its hydrolysis to carboxyl occurs when 4-cyanopyridine methiodide is treated with alkali, giving l-methylpyrid-4-one . Similarly, 2-cyanopyridine methiodide gives 1-methylpyrid-2-one and is the intermediate in the conversion of pyridine-2-aldehyde oxime methiodide into l-methylpyrid-2-one in the range pH 7-13. 

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