Summary Benzoylformanilide condenses in the presence of diethylamine with one mole of acetone and two moles of diethyl malonate to give products analogous to those of isatin. The diethyl malonate product is decomposed by heat, losing a molecule of diethyl malonate and forming a maleinanil derivative through ring closure. Ethyl phenylacetate reacts slowly with benzoylformanilide under similar conditions to yield symmetrical diphenylmaleinanil.
