Iminyls. Part 5. Intramolecular hydrogen abstraction by alkyl(aryl)iminyls. A new tetralone synthesis

Abstract

Tetralones can be synthesised by oxidation of phenylalkylideneamino-oxyacetic acids with persulphate. The iminyls formed initially abstract a γ-hydrogen from the alkyl chain and the resulting carbon radicals then cyclise onto the benzene ring. The same iminyls, when generated in benzene solution by thermolysis of imino-oxyperacetates, do not abstract γ-hydrogen unless trifluoroacetic acid is present. Hence, the hydrogen abstracting species in both cases is thought to be the protonated iminyl (RArC[graphic omitted]).