GREEN, RAPID, SIMPLE, AND AN EFFECTIVE ONE-POT MULTICOMPONENT STRATEGY FOR SYNTHESIS OF NOVEL DIHYDROPYRANO[2,3-C]PYRAZOL-6-AMINES IN AQUEOUS MEDIUM

Sadeq Hamood Saleh Azzam; Aisha Siddekha; MA Pasha

doi:10.22270/ujpr.v5i2.383

Sadeq Hamood Saleh Azzam Department of Chemistry, Sana’a University, Sana’a, Yemen
Aisha Siddekha Department of Studies in Chemistry, Jnana Bharathi Campus, Bangalore University, Bangalore–5 60056, India.Department of Chemistry, Government First Grade College, B.H. Road, Tumkur-572102, Karnataka, India
MA Pasha Department of Studies in Chemistry, Jnana Bharathi Campus, Bangalore University, Bangalore–5 60056, India

10.22270/ujpr.v5i2.383

Keywords:

Araldehydes, ethyl acetoacetate, fluoro phenylacetonitrile, hydrazine hydrate, pyrano[2,3-c]pyrazol-6-amines, water

Abstract

Objectives: A series of new dihydropyrano [2,3-c]pyrazol-6-amines in this investigation study, are synthesized by the strategy of one-pot four component reaction in an aqueous medium.

Methods: After getting optimum conditions the reaction of different substituted aromatic aldehydes, ethyl acetoacetate, hydrazine hydrate, and phenylacetonitrile catalysed by Sodium hydrogen sulphate NaHSO₄ (0.5 m mol) by refluxing in ethanol-water (1:1) (5 ml) and heated at 80 ^oC. The synthesized molecules product was filtered, washed with water to get nearly pure product in excellent yield.

Results: The pure products which were got in a short duration, with excellent yield (80 – 87%). Those new compounds were identified by using spectroscopic techniques FT-IR, ¹H-NMR and ¹³C-NMR.

Conclusion: In conclusion, the usefulness of this one-pot multicomponents protocol include easily available starting materials, facile, simple and environment-friendly procedure, and easier separation of products by filtration.