Synthesen von Heterocyclen, 177. Synthesen von 4‐Chromanon‐2‐carbonsäuren

Abstract

Die Fumarsaure-monophenylester 1 a-d liefern bci dcr Fricsschen Vcrschiebung die Bcnzoylacrylsaurcn 2ad, welchc unter dcr Einwirkung von Na2COyLosung zu den 4-Chromanon-2-carbonsauren 3ad wcitcrreagieren. Syntheses of Heterocycles, 1771). -Syntheses of 4-Chromanone-2-carboxylic AcidsUnder the conditions of the Fries reaction the phenyl hydrogen fumarates l ad give the benzoylacrylic acids 2a-d, which, on further reaction with sodium carbonate solution yield the 4-chromanone-2-carboxylic acids 3ad.