Studies on Tertiary Amine Oxides. XXXI. Reactions of Aromatic N-Oxides with Antipyrine in the Presence of Acylating Agents.

Abstract

Antipyrine (I) was shown to react smoothly with quinoline 1-oxide (II), 4-chloroquinoline 1-oxide (VII) and isoquinoline 2-oxide (IX) in the presence of benzoyl chloride, producing 4-(2-quinolyl) antipyrine (III) (63.4%) together with 4-(4-quinolyl) antipyrine (IV) (16.4%), 4-(4-chloro-2-quinolyl) antipyrine (VIII) (88%) and 4-(1-isoquinolyl) antipyrine (X) (79%), respectively. Although tosyl chloride was not effective as an acylating agent for these reactions, methosulfate of II could enter into reaction with I to give III in 38.4% yield. Nucleophilic reactivity of I was considerably lower compared with that of cyclohexanone enamine, and no satisfactory result was obtained from similay treatment of pyridine 1-oxide.