Hydrochloric Acid → 1-(6-Amino-2H-1,3-benzodioxol-5-yl)-2-chloroethan-1-one

Participants

Reaction Steps

To 2'-acetylamino-4',5'-methylenedioxy-2-chloroacetophenone (0.9 g, 3.53 mmol) or an equivalent amount of 2'-pivoylamino-4',5'-methylenedioxy-2-chloroacetophenone in ethanol (60 mL) at about 5° C. is added, dropwise, conc. HCl (12.5 mL, 149.7 mmol). The reaction mixture is then heated at reflux for about an hour, then poured over 2N NaOH/ice (80 mL/60 g) and washed with ethyl acetate (3×70 mL). The organic portions are combined and washed with brine (50 mL), dried (anhydrous sodium sulfate) and concentrated in vacuo to yield a greenish-yellow solid. This solid is recrystallized from ethyl acetate/isopropanol/hexane, treated with activated charcoal, to yield 2'-amino-4',5'-methylenedioxy-2-chloroacetophenone (0.39 g, 52% of theory).

Provenance & Evidence