Electronic and vibrational spectra of chalcone analogs derived from 4- and 5-nitropyrroles

The electronic absorption spectra of ten chalcone analogs derived from 4- and 5-nitropyrroles have been measured in solution in ethanol, dioxane, concentrated sulfuric acid, and 20% ethanolic caustic potash and interpreted. The IR spectra of these compounds and also of 4- and 5-nitro-2-acetylpyrroles and 5-nitropyrrole-2-aldehyde have been measured in the 3700-500 cm^–1 region, an assignment of frequencies has been carried out, and considerations have been put forward on the connection between the characteristic features of the absorption and the chemical structure.