Microwave-Assisted One-Pot Synthesis of α-Fluoro-α,β-Unsaturated Esters under Solvent-Free Conditions

Abstract

A microwave-assisted approach for the synthesis of α-fluoro-α,β-unsaturated esters from ethyl bromofluoroacetate, aldehydes, and triphenylphosphine in the presence of Zn-Cu under solvent-free conditions was achieved. The reaction was accomplished within five minutes with good product yields.

Key words

microwave irradiation - solvent-free - α-fluoro-α,β-unsaturated ester

References and Notes

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19

All reactions were conducted under an XH-100A microwave synthesis/extraction instrument, which was made by Beijing Xiang Hu Science and Technology Development Co. Ltd. Triphenylphosphine (1.2 mmol), ethyl bromofluoroacetate (1.2 mmol), aldehyde (1.0 mmol), and Zn-Cu (0.1 g) were added into an oven-dried round-bottom flask. The mixture was stirred under microwave irradiation, which was set at 1000 W, 150 ˚C for 5 min. The product was purified by chromatography on SiO₂ with EtOAc and PE (60-90 ˚C).