Hydrochloric Acid → 1-(3-Chloro-2-methylquinoxalin-5-yl)ethanone

Participants

Reaction Steps

1-(3-Fluoro-2-methylquinoxalin-5-yl)ethanone (126g, 2.00 g, 9.79 mmol) was treated with HCl (4.0 M solution in 1,4-dioxane; 24.49 ml, 98 mmol), and the homogeneous reaction was fitted with a drying tube. After 6 h the reaction was concentrated in vacuo, and the solid was taken up in DCM. Solid NaHCO3 was added cautiously with rapid stirring; and saturated aq. NaHCO3 was sequentially added cautiously with rapid stirring. The mixture was partitioned between saturated NaHCO3 and DCM. The aq. layer was extracted with DCM (2×), and the combined organics were dried over anhydrous Na2SO4, filtered, and concentrated in vacuo to give 1-(3-chloro-2-methylquinoxalin-5-yl)ethanone (254a, 99% yield) as an orange-brown solid. MS (ESI, pos. ion) m/z: 221.0 (M+1).

Provenance & Evidence