Concepedia

Ultrasonic-accelerated rapid protocol for the improved synthesis of pyrazoles

Nhlanhla Gracious Shabalala, Ramakanth Pagadala, Sreekantha B. Jonnalagadda

Ultrasonics Sonochemistry · 2015 · 88 citations · 42 references

DOIFull text

Open access

Abstract

A simple, catalyst-free, green synthetic protocol is described for the one-pot synthesis of pyrazoles via multicomponent reaction of aromatic aldehydes, hydrazine monohydrate and ethyl acetoacetate and malononitrile/ammonium acetate in water under ultrasound irradiation. This protocol avoids traditional chromatography and purification steps and it affords highly selective conversion with no byproducts.

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