Portal de Periódicos da CAPES

Convenient synthesis of 3‐arylazopyrazoles and 2‐arylazo‐1,3,4‐Δ 2 ‐ thiadiazoline derivatives from 3‐nitroformazans

1985; Wiley; Volume: 22; Issue: 3 Linguagem: Inglês

10.1002/jhet.5570220340

1943-5193

Abdou O. Abdelhamid, Ikhlass M. Abbas, Magda A. Abdallah, Abdelgawad A. Fahmi, Ahmad S. Shawali,

Synthesis and Biological Evaluation

Abstract Reactions of 3‐nitro‐1,5‐diarylformazans 1a‐c with carbanions of acetylacetone, dibenzoylmethane, aceto‐acetanilide, benzoylacetonitrile, ω‐benzenesulfonylacetophenone and malononitrile yielded the corresponding 3‐arylazopyrazole derivatives 4‐9 respectively. Reactions of 1 with nucleophiles result in displacement of the nitro group and the formation of the corresponding 3‐substituted formazans 10‐13 . Treatment of 1 with potassium thiocyanate gave, however, 5‐imino‐2‐arylazo‐1,3,4‐Δ 2 ‐thiadiazolines 14. Structural assignments have been made on the basis of spectral and elemental analyses, chemical behaviour and alternate synthesis wherever possible.