Trifluoroacetic acid → 1-(2-(4-aminopiperidin-1-yl)ethyl)-7-fluoroquinoxalin-2(1H)-one

Participants

Reaction Steps

A solution of tert-butyl{1-[2-(7-fluoro-2-oxoquinoxalin-1(2H)-yl)ethyl]piperidin-4-yl}carbamate (Intermediate 141, 240 mg, 0.62 mmol) in dichloromethane (20 mL) was treated with trifluoroacetic acid (15 mL). After 45 minutes, the reaction was concentrated to dryness, the residue taken up in methanol/chloroform (15:85, 30 mL) and washed with saturated sodium bicarbonate solution. The aqueous layer was re-extracted with methanol/chloroform (15:85, 3×30 mL. The combined organic phases were dried over magnesium sulfate and concentrated to dryness to give 170 mg (quantitative) of the crude product as an oil.

Provenance & Evidence