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

Participants

Reaction Steps

To a solution of lithium aluminum hydride (28.2 g, 742 mmol) in THF (1500 mL) at 0° C. was added 3,4-dihydroquinoxalin-2(1H)-one (50 g, 337 mmol) portion wise. The reaction mixture was warmed up to room temperature and heated at 80° C. for 4 h. The reaction mixture was cooled to 0° C. and quenched with water (20 mL) dropwise. The insoluble inorganics was filtered through CELITE®. The filtrate was dried over Na2SO4, filtered, concentrated to afford 1,2,3,4-tetrahydroquinoxaline (36 g, 268 mmol, 80% yield). NMR: 1H NMR (400 MHz, CDCl3) δ ppm 6.6 (2H, m), 6.5 (2H, m), 3.65 (2H, bs), 3.40 (4H, s).

Provenance & Evidence