The question of whether the title compounds could be decarboxylated to cyclopropanone derivatives was answered in the affirmative by the following observations.(1) Compound 1 la was decarboxylated by 1, 2, 3-indantrione in acetonitrile, benzene, or methanol. The initially formed intermediate could be trapped by N-phenylmaleimide (to form 31, by diethyl azodicarboxylate (to form an unstable adduct), by ninhydrin itself (to form 5) or by a proton ...
