Acetyl chloride → 4-Acetyl-3,4-dihydroquinoxalin-2(1H)-one

Participants

Reaction Steps

Acetyl chloride (0.36 ml) is added to 1,2,3,4-tetrahydroquinoxalin-2-one (IV, EXAMPLE 1, 0.676 g) and triethylamine (0.76 ml) in THF (8 ml) at 0°. After stirring for 1 hr, the solvent is removed under reduced pressure and the residue is partitioned between dichloro-methane and aq. sodium bicarbonate. The layers are separated, the organic phase is filtered through sodium sulfate and concentrated. The concentrate is crystallized from methanol/methylene chloride/hexane to give the title compound, mp 164°-165°; NMR (CDCl3) 2.28, 4.54, 7.00, 7.11, 7.21 and 9.19 δ.

Provenance & Evidence