ANIL SYNTHESE .21. PREPARATION OF STILBENYL DERIVATIVES OF PYRAZOLES

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. Copyright © 1979 Verlag GmbH & Co. KGaA, Weinheim