Ring-chain transformation of 4-aroyl-5-phenylamino-2,3-dihydrothiophene-2,3-diones: Facile and efficient synthesis of novel pyrrolo[2,3-c]pyrazol-3(2H)-ones and 1,2-dihydro-5H,6H-pyridazine-5,6-diones

ABSTRACT

Seven, novel pyrrolo[2,3-c]pyrazol-3(2H)-one and 1,2-dihydro-5H,6H-pyridazine-5,6-dione chromophores were synthesized by the reaction of 4-aroyl-5-phenylamino-2,3-dihydrothiophene-2,3-diones with cyanoacetohydrazide and arylhydrazines such as phenylhydrazine and 4-nitrophenylhydrazine. These derivatives were characterized by elemental analysis, IR, UV-Visible, ¹H, ¹³C NMR and mass spectroscopy. Spectral characteristics of the compounds were studied in four organic solvents of differing polarity.

GRAPHICAL ABSTRACT

KEYWORDS:

• Ring-chain transformation
• 2,3-dihydrothiophene-2,3-dione
• cyanoacetohydrazide
• arylhydrazine
• pyrrolo[2,3-c]pyrazol-3(2H)-one
• 1,2-dihydro-5H,6H-pyridazine-5,6-dione

Disclosure statement

No potential conflict of interest was reported by the authors.

Correction Statement

This article has been republished with minor changes. These changes do not impact the academic content of the article.