Routes to N-vinyl-nitroimidazoles and N-vinyl-deazapurines

Article abstract of DOI:10.1002/jhet.5570410508

The preparations of 4- and 5-nitro-1-vinylimidazole (2 and 7) are described. Selective reduction of the nitro group using Fe/dil HCl is achieved for the 4-nitro derivative but this is not effective when ethoxymethylenemalononitrile is used to trap the amine. For 5-nitroimidazole studies the N-vinyl substituent is kept masked as a 2-chloroethyl group, which remains unchanged during catalytic reduction of the nitro function (Pd/C), and is revealed by HCl elimination at a later stage. In this way, the 1-deazapurine 13 and the tricyclic derivative 14 have been prepared.