Anil-Synthese. 21. Mitteilung. Über die Herstellung von stilbenyl-derivaten des pyrazols

Preparation of Stilbenyl Derivatives of Pyrazoles Schiffs bases derived from 1-, 3- and 5-(p-formylphenyl)phenylpyrazoles and p-chloroaniline are reacted with various p-tolyl substituted aromatic heterocycles in the presence of dimethylformamide and potassium hydroxide or potassium t-butoxide to yield the corresponding heterocyclic substituted stilbenes (anil synthesis). Introduction of a chloro substituent in the 4- and 4,5-positions of the pyrazole system causes a decrease in yield and a hypsochromic shift in the absorption and fluorescence maxima of the title compounds.