Title:
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Investigation of synthetic routes leading to vinylphenylhydrazines and vinylheterocycles
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With the object of assessing projected syntheses of vinylheterocycles from hydrazinostyrenes, the uses of arylhydrazines in heterocyclic synthesis and methods of preparation of substituted styrenes and arylhydrazines, are reviewed. Possible synthetic routes to a hydrazinostyrene, taking into account the high reactivity of both substituents, and the formation of polymeric vinylheterocycles from the hydrazinostyrene, are then discussed. Attempts to prepare m-hydrazinostyrene are described, in which m-andnocinnamic acid was diazotised, and reduced to m-hydrazinocinnamic acid various procedures were investigated, but the amphoteric nature of the compounds rendered manipulation somewhat difficult. Attention was then turned to the formation of vinylheterocycles by decarboxylation of beta-(heterocyclic)-acrylic acids, and beta-(4-quinolyl)-acrylic acid was subjected to several decarboxylation procedures, but the principal product is inferred to have been a poly-4-vinylqiuinoline. m-Hydrazinostyrene was finally prepared by the following routes m-nitroacetophenone was reduced to a-methyl-m-nitrobenzyl alcohol, and the latter was dehydrated with phosphoric acid to m-nitrostyrene; this was then reduced to m-aminostyrene, diazotisation of which, and reduction with stannous chloride, yielded m-hydrazinostyrene.
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