| Popis: |
It has been observed that a convenient route to pure β-anilinoacroleineanil-bases, bearing nucleophilic as well as electrophilic substituents in the p.-position of their phenyl groups, lies through the acid-catalysed condensation of propiolaldehyde acetal with the appropriately para-substituted aniline-compounds, followed by the filtration of the resulting crude anil-salts through a chromatographic column filled with alumina. The absorption data of the new dyestuffs were recorded in neutral and in acid medium. Their knowledge induced a thorough investigation of the peculiar optical properties of substituted anilinovinyl salts of heterocyclic. nuclei (which may be considered as the structural hybrids between the monomethinic cyanines and the β-anilinoacrolein anil-salts). The aberrant behavior of anilinovinyl-salts towards the “deviation” concept is discussed and a tentative interpretation of their abnormal optical comportment is proposed. |
