Title:
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The preparation and reactions of some azaindoles
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A review is gives of the work which has been carried out on the synthesis of some azaindoles and their simple derivatives; the various systems of nomenclature which have been employed are described. The preparation of 2-methyl-6-azaindole starting from 4-hydroxypyridin-2:6-dicarboxylic acid, using a procedure described in the literature has been examined in some detail. Attempts were made to prepare 3-nitno-4-methylpyridine, on intermediate in tills scheme of synthesis, by direct nitration of 4-methylpyridina, but were unsuccessful. Attention was directed to the synthesis of 6-methyl-4-azmindole and its 2-methyl and 2-phenyl derivatives by the application of Madelung's indole synthesis. This was successfully carried out. The chemical behaviour of 2:5-dimethyl-4-azaindole has been examined and a number of derivatives have been prepared. Most of these compounds have been oriented by a method of oxidative degradation; the remainder have been oriented by analogy to the corresponding indole derivative. The structure of the compound obtained on condensation of equimolecular proportions of 2:5-dimethyline 4-arnidolo and benzaldehyde has not been elucidated, although attempts were made to synthesize unambiguously, both the compound itself and its reduction product. The evidence for and against possible structures of the condensation product is described and discussed.
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