O-Phenylenediamine → 2(1H)-Quinoxalinone, 3,4-dihydro-

Participants

Reaction Conditions

Reaction Steps

To a solution of benzene-1,2-diamine (150 g, 1387 mmol) and triethylamine (193 mL, 1387 mmol) in DMF (Ratio: 20 times, Volume: 3000 mL) was added ethyl bromoacetate (232 g, 1387 mmol). The reaction mixture was heated at 120° C. for 36 h. The reaction mixture was cooled to room temperature and diluted with EtOAc and water. The organic layer was separated and washed with brine, dried over Na2SO4, filtered, and concentrated to give crude material. The crude product was purified via ISCO, eluted with 50% EtOAC/hexane to afford 3,4-dihydroquinoxalin-2(1H)-one, Intermediate E-1A (140 g, 945 mmol, 68.1%). 1H NMR (400 MHz, CDCl3) δ ppm 7.7 (1H, bs), 6.9 (1H, m), 6.75 (1H, m), 6.70 (2H, m), 4.0 (1H, s), 3.85 (1H, bs).

Provenance & Evidence