Background: Pyrazoles are useful intermediates in pharmaceutical, agrochemical,
photographic and other fields. Pyrazole nucleus has been reported to possess a wide
spectrum of biological properties such as anti-inflammatory, anti-depressant, anti-bacterial,
anti-tumor, anti-microbial, anti-viral, anti-fungal and anti-filarial agent. The aims of this paper
to introduce readers the polyvinylsulfonic acid (PVSA) as a new catalytic system for the
synthesis of pyrazoles. The PVSA was found to be an inexpensive, stable, easy to handle
and biodegradable catalyst.
Methods: The catalyst is well characterized using various techniques such as IR, XRD and DSC. All products
were characterised using melting point, GC-MS, 1H and 13C NMR techniques.
Results: The various acidic catalysts were compared with PVSA under optimized reaction condition and it
was found that PVSA giving better yield of desired product. Different reaction parameters such as solvent,
temperature, time, and substrate were studied to achieve optimal catalyst performance using PVSA as a catalytic
Conclusion: We have described PVSA as a novel Bronsted acid catalyst for the synthesis of pyrazoles. The
catalyst was isolated by simple filtration process and recycled up to four cycles providing the excellent yield
of the pyrazole derivatives.