Premium
NbCl 5 ‐Catalyzed One‐Pot Four Component Synthesis of Spiro Pyrazole and Benzo[7, 8]chromene Derivatives
Author(s) -
Veeramani Vairaperumal,
Muthuraja Perumal,
Prakash Sengodu,
Senthil Kumar Muthiah,
Susaimanickam Antony,
Manisankar Paramasivam
Publication year - 2018
Publication title -
chemistryselect
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.437
H-Index - 34
ISSN - 2365-6549
DOI - 10.1002/slct.201802036
Subject(s) - catalysis , phenylhydrazine , pyrazole , chemistry , yield (engineering) , solvent , lewis acids and bases , organic chemistry , ethanol , combinatorial chemistry , materials science , metallurgy
In this work, we have designed a novel green method for synthesis of a set pharmaceutically important spiro pyrazole and benzo[7, 8]chromene derivatives. These derivatives have been synthesized from various substituted isatins in turns with ethylacetoacetate, 2‐hydroxy‐1,4‐naphthaquionone/malonitrile and hydrazines or phenylhydrazine in presence of different catalysts in one‐pot four component method. We have optimized the synthetic conditions such as catalyst, solvent and time of reaction to get the maximum yield. Various lewis acids as catalyst and polar solvents as reaction medium were used in the multicomponent reactions (MCRs). Among the different catalysts and solvents tried NbCl 5 and ethanol have been identified as most effective catalyst and solvent respectively. The synthesized compounds are confirmed by FT‐IR, 1D and 2D NMR spectroscopic techniques.