Open Access

Novel Azo-fused Dipyrazolopyridine Derivatives using Waste Orange Peel-derived C-SO3H Nanopowder as an Efficient and Reusable Catalyst

Nagarajan Nagasundaram, lalitha2531@yahoo.co.in
Department of Chemistry, Periyar University, Salem, TN, India. Sivagiri Sumitha, lalitha2531@yahoo.co.in
Department of Chemistry, Periyar University, Salem, TN, India. Appaswami Lalitha lalitha2531@yahoo.co.in
Department of Chemistry, Periyar University, Salem, TN, India.

---

---

---

Abstract

A new series of structurally diverse azo-fused dipyrazolopyridines has been synthesized via one-pot pseudo-six-component reaction of various substituted aryl azo-salicylaldehydes with ethyl acetoacetate, hydrazine hydrate and ammonium acetate, using waste orange peel-derived carbon modified sulfonic acid (C-SO₃H) as a mild, efficient and inexpensive heterogeneous catalyst. The prepared catalyst was characterized by FT-IR, XRD, SEM, EDX and XPS studies. The catalytically synthesized compounds were characterized by FT-IR, ¹H NMR and ¹³C NMR. The notable advantage was the use of a recyclable powder catalyst (C-SO₃H) for excellent yields and rapid formation of the desired azo-fused dipyrazolopyridines with a simple work-up procedure.

Full Text

Reference

---

Kandepi, V. V. K. M., Narender, Synthesis of N-heterocyclic compounds over zeolite molecular sieve catalysts: an approach towards green chemistry, N. Catal. Sci. Technol., 2, 471–487(2012).

https://dx.doi.org/10.1039/C2CY00162D

Kumar, B. S., hakshinamoorthy, A., Pitchumani, K., K10 montmorillonite clays as environmentally benign catalysts for organic reactions, Catal. Sci. Technol., 4, 2378–2396(2014)

https://dx.doi.org/10.1039/C4CY00112E

Ryoo, R., Joo, S. H., Jun,S., Synthesis of highly ordered carbon molecular sieves via template-mediated structural transformation, J. Phys. Chem. B., 103, 7743–7746(1999).

https://dx.doi.org/10.1021/jp991673a