Cyano-7-azaindole

Chou PT, Yu WS, Wei CY et al (2001) Water-catalyzed excited-state double proton transfer in 3-cyano-7-azaindole the resolution of the proton-transfer mechanism for 7-azaindoles in pure water. J Am Chem Soc 123 3599-3600... 

Carbonation of the sodium salt of 7-azaindole (105, R = H) gives 7-azaindole-3-carboxylic acid (106, R = OH) in low yield. Robison and Robison also prepared it from 7-azaindole-3-carboxaldehyde (105, R = CHO) either by direct oxidation (28 % yield) or through the oxime, which was dehydrated with acetic anhydride to l-acetyl-3-cyano-7-azaindole. This compound was hydrolyzed in water to give 3-cyano-7-azaindole (105, R = CN) in refluxing hydrochloric acid it... 

Azaindoles are readily acylated on the pyrrole nitrogen by warming on a water bath with acid anhydrides or with acid chlorides in the presence of carbonate or pyridine. Good yields were obtained by this procedure for the following compounds l-acetyl-7-azaindole, 1-benzoyl- and l-benzenesulfonyl-7-azaindole, l-benzoyl-2-methyl-7-azaindole, 1-ethoxycarbonyl- and l-chloroacetyl-7-azaindole, l-acetyl-3-cyano-7-azaindole, 1-benzoyl-4-azindole, and 1-acetyl- and l-benzoyl-2,5-dimethyl-4-azaindole. The only reported failure was with 5-methyl-2-phenyl-4-azaindole, which failed to react with acetic anhydride or benzoyl chloride. 2-Methyl-7-azaindole-3-acetic acid was acylated by treatment of its ierGbutyl ester with sodium hydride in dimethylformamide, followed by p-chlorobenzoyl chloride. ... 

Hsieh CC, Chen KY, Hsieh WT et al (2008) Cyano analogues of 7-azaindole probing excited-state charge-coupled proton transfer reactions in protic solvents. ChemPhyChem 9 2221-2229... 

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