Benzimidazole-2-acetonitrile. reaction with

A method [116] was developed for determining formate as benzimidazole after reaction with o-phenylenediamine at 130 °C for 2 h in 1M perchloric acid. The benzimidazole was extracted from the reaction mixture with ethyl acetate/ethanol (9 1, v/v). The HPLC system was a Cjg column, isocratic elution with a mixture of phosphate buffer (pH 2.1) and acetonitrile, and detection at 267 nm. This procedure was employed to determine the formate concentration in human urine and rat liver and urine, and to measure the activity of formaldehyde dehydrogenase [116]. 

The reaction of methyl propargylate (propiolate) with benzylimidazole and its 2-alkyl and aryl derivatives in acetonitrile leads to the formation of the methyl esters of 3-fran -(l-benzimidazolyl)acrylic acid 106a and 107a, b, whereas the reaction with benzimidazole in methanol leads exclusively to the corresponding cis isomer 106b in the absence of the solvent, the treatment of benzimidazole with methyl propiolate gives a mixture of compounds 106a, b, and pyrrolo[l,2-a]ben-zimidazole 108 (Fig. 3.5). At the same time, the 2-isopropyl, 2-phenyl, and 2-benzyl derivatives of benzimidazole in reaction with methyl propiolate without a solvent form the pyrrolo[l,2-a]quinoxalines 114 and 115 (Scheme 3.35) (Acheson and Verlander 1973). 

There has been a study of photo-induced intramolecular cyclization of some o-haloarylheterylamines which may lead to pyrido[l,2-a]benzimidazole derivatives. Several studies have been reported of photochemical nucleophile-olefin combination, aromatic substitution (photo-NOCAS) reactions with fluoride, cyanide, or acetonitrile " acting as the nucleophile. In the example illustrated in Scheme 3,... 

One of the processes available to electronically excited enones is isomerization about the carbon-carbon double bond. Cis cycloalkenones with seven or eight atoms can undergo photoisomerization to strained trans cycloalkenones. In turn, the trans double bond can undergo addition reactions with alcohols or amines. For example, irradiation (350 nm) of cyclohept-2-enone (90) in acetonitrile containing benzimidazole led to a 94% conversion to 3-(lH-benzo[d]imidazol-l-yl)cycloheptanone (91, equation 12.68). ... 

When nitroimidazoles and -benzimidazoles are subjected to electrochemical reduction, the initially formed unstable radical anions subsequently decompose with elimination of hydrogen. Thus, in acetonitrile, 2-substituted 5(6)-nitrobenzimidazoles generate hydrogen as a result of bimolecular reaction of two primary radical anions <85CHE688>. 

Reaction of ds-dichloro-oxobis (4-phenylthiosemicarbazide)molybdenum(VI) with pyridine or with benzimidazole, studied in acetonitrile, follows a consecutive first-order kinetic pattern, with replacement of the second chloride 44 and 28 times slower than of the first, respectively. In all cases reaction is first order in the incoming ligand, consistent with the expected associative nature of ligand replacement at this high-charge center. ... 

In 1984, Tsupak and co.[64] synthesized 2-(l-adamantyl)benzimidazole (68) with 45% yield by substitution of sulpho group in benzimidazole-2-sulfonic acid with adamantly radical. The reaction was carried out in aqua acetonitrile solution. The adamantyl radical was obtained by oxidativ decarboxylation of adamantanecarboxylic acid with ammonia persulfate in silver nitrate aqua solution. 

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