Reactions of cyclic oxalyl compounds - 32. Photochemical and thermal 2+2-cycloadditions of diphenylketene and diphenylketen-N-methyl-phenyl-imine to five-membered heterocyclic 23-diones

Article abstract of DOI:10.1016/S0040-4020(01)96034-X

The heterocyclic 2,3-diones 1-3 have been found to undergo photochemical and thermal 2+2-cycloaddition reactions via their 3-carbonyl group to diphenylketene and the diphenylketen-N-(4-methylphenyl)-imine. These reactions afford rearranged cycloadducts as well as 2+2-cycloreversion products.