Conditions for the Selective Conversion of Quaternary 3‐Anilino‐1,5‐dimethylpyrazolium Salts into 3‐Anilino‐1,5‐dimethylpyrazole.

Abstract

Pyrazole derivatives R 0180Conditions for the Selective Conversion of Quaternary 3-Anilino-1,5-dimethylpyrazolium Salts into 3-Anilino-1,5-dimethylpyrazole. -Selective and highly efficient N-decyanoethylation of the pyrazolium salt (V) furnishing the desired 3-anilino--1,5-dimethylpyrazole (VI) is achieved on boiling in aqueous ammonia. Attempts to obtain the target compound (VI) by N-debenzoylation or N-deethylation of corresponding pyrazolium salts fail or appear to be significantly less regioselective, respectively. -(DZVINCHUK, I. B.; KARTASHOV, S. A.; VYPIRAILENKO, A. V.; DOLLER, U.; LOZINSKII, M. O.; Chem. Heterocycl.