O-Phenylenediamine → 2H-1,5-Benzodiazepin-2-one, 4-ethoxy-1,3-dihydro-

Participants

Reaction Conditions

Reaction Steps

To a solution phenylenediamine (17.2 g, 159.2 mmol) and acetic acid (0.4 mL) in xylenes (225 mL) at 140° C. was added 3,3-diethoxyacrylic acid ethyl ester (30.0 g, 159.2 mmol) in xylenes (80 mL) dropwise over 50 minutes. The reaction was heated at 140° C. for 2 hours, was cooled to room temperature, and was stirred for 24 h. The resulting white precipitate was filtered, was washed with ether (100 mL), and was dried under vacuum to provide 18.37 g of 4-ethoxy-1,3-dihydro-benzo[b][1,4]diazepin-2-one as a white fluffy solid. MS 205 (M+1).

Provenance & Evidence