Ketene. Part 24. The reactions of N-(fluoren-9-ylidene)methylamine N-Oxide with dimethvlketene and ketene

Abstract

The principal products of the reaction of the N-methylnitrone (1a) with dimethylketene have been identified as the dioxolane derivative (6) and its hydrolysis product (7). Fluoren-9-yl isocyanide appears to be an intermediate in this reaction. Ketene reacts with nitrone (1a) and its N-ethyl and N-isopropyl analogues to give the cyclobutanedione (15) as the only isolated product. Compound (15) has been synthesized from fluoren-9-ylidenemalonic acid.