A Novel Method for the Synthesis of Oxazolocoumarin Derivatives

Abstract

Anodic oxidation of 7-hydroxycoumarin derivatives 1a-f in anhyd acetonitrile-lithium perchlorate at constant potential between 1.70-1.80 V (vs. Ag/10^-2 M Ag⁺) using an undivided cell and platinium gauze electrodes leads to the formation of the corresponding oxazolocoumarin derivatives 2 and/or 3 according to the position of the second OH group in the benzene ring of the coumarin derivatives 1e,f. The formation of these oxidation products is discussed.

Key words

oxidations - carbocations - coumarins - electrochemistry - quinones

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