Intramolecular Cycloaddition Reactions of N-Sulfonyl Nitrile Imides Bearing Alkenyl Groups

Abstract

Abstract The reaction of the p-tolyl(or phenyl)sulfonylhydrazones of some 2-(alkenyloxy)benzaldehydes with lead tetraacetate leads, via the nitrile imide intermediates, Ar–\overset+C=N–\overset−N–SO2–C6H4–X-p, to intramolecular 1,3-dipolar cycloadducts and 1-acetyl-2-aroyl-1-[p-tolyl(or phenyl)sulfonyl]hydrazines in 20–65% and 7–70% yields respectively, while the intermolecular reactions of the benzaldehyde p-tolylsulfonylhydrazone with a dipolarophile such as acrylonitrile or styrene in the presence of lead tetraacetate gives only 1-acetyl-2-benzoyl-1-(p-tolylsulfonyl)hydrazine. The treatment of the N-(p-tolylsulfonyl)-o-(allyloxy)benzohydrazonoyl chloride (10) with triethylamine or by refluxing a benzene solution of 10 also gives an intramolecular 1,3-dipolar cycloadduct in a good yield.