Microwave-Assisted Solid-Support Synthesis of Pyrazolino/Iminopyrimidino/Thioxopyrimidino Imidazolines

Abstract

An expeditious solvent-free synthesis of pyrazolino/iminopyrimidino/thioxopyrimidino imidazoline derivatives from readily accessible oxazolones on solid support using microwaves is described. The reaction time has been brought down from hours to minutes with improved yield as compared to conventional heating.

Key words

microwave irradiation - solid-support synthesis - heterocycles

References

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21

Aluminium Oxide Basic, Brockmann I (Aldrich Chem. Co., Cat. No. 19, 944-3, ~150 mesh, 58 Å, Surface area 155 m²/g)was used. Alumium Oxide Neutral, Brockmann I (Aldrich Chem. Co., Cat. No. 19, 997-4, ~150 mesh, 58 Å, Surface area 155 m²/g)was used.