Cyclic nitrones. I. Reactions of α-keto nitrones at nitrone carbon

Abstract

The chemistry of 3,4,5,6-tetrahydro-3-oxopyridine 1-oxides has been studied with respect to: reaction with hydrazine-the 6,6-dimethyl compound (IV) gave a hydrazone (VII) by ring contraction following initial attack at C 2; (ii)(ii) 2-arylation with diazonium salts, e.g. conversion of (III) into (XIII); (iii) acid- and base-catalysed deuterium exchange at C 2, C 4, and C 6; (iv)(iv) oxidation of the 5,5-dimethyl compound (III) by chromate ion to a 2,2?-linked dimer (XV).