Ultrasound-Assisted Conjugate Addition of Organometallic Reagents to 3-Diethylphosphonocoumarin

Abstract

A comparative investigation on the 1,4-conjugate addition of various nucleophiles to diethyl ester of 2-oxo-2H-1-benzopyran-3-phosphonic acid under thermal and ultrasound promoted conditions is presented. The approach enables the usage of a simpler experimental setup and mild reaction conditions as well as excellent yield reproducibility. The trans isomers isolated showed high diastereoselectivity and the absolute structure of one of the products was confirmed by X-ray diffraction analysis.

Key words

1,4-conjugate addition - coumarins - organometallic reagents - phosphonates - ultrasound

• References and Notes

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