A new and efficient palladium-catalyzed synthesis of a 2,3,4,5- tetrahydro-1H-2,4-benzodiazepine-1,3-dione derivative

Article abstract of DOI:10.1016/S0040-4039(99)00232-4

The palladium-catalyzed intramolecular cyclization of 1-butyl-1(o- iodobenzyl)-3-phenylurea 1 at 80°C in the presence of carbon monoxide at atmospheric pressure gives the corresponding 2,3,4,5-tetrahydro-1H-2,4- benzodiazepine-1,3-dione derivative 2 in 91% yield. Yield and selectivity are strongly affected by the solvent.