The relative nucleophilicities of fluoride and aryloxy ions towards acyl and nitroaryl groups

Abstract

Fluoride ion as potassium fluoride–18-crown-6 reacted with p-nitrophenyl sulphonates exclusively at the sulphonyl group with phenoxide displacement. The 2,4-dinitrophenyl sulphonates showed, in addition, minor attack at aryl group with sulphonate displacement. The aryloxy anions generated reacted further with aryl sulphonate to generate the diaryl ether. This distinction between the nucleophilicities of fluoride and aryloxy anions was shown to apply also to carboxy and phosphoryl centres.