Trifluoroacetic acid → 1-(2-(4-((2,3-dihydro-1,4-benzodioxin-6-ylmethyl)amino)piperidin-1-yl)ethyl)-7-fluoroquinoxalin-2(1H)-one

Participants

Reaction Steps

To 3 mL of a chloroform solution containing 631 mg of tert-butyl (2,3-dihydro-1,4-benzodioxin-6-ylmethyl)(1-(2-(7-fluoro-2-oxoquinoxalin-1(2H)-yl)ethyl)piperidin-4-yl)carbamate, 3 mL of trifluoroacetic acid was added and stirred at room temperature for 6 hours. After solvents of the reaction mixture were removed under reduced pressure and the residue was alkalized by aqueous saturated sodium hydrogen carbonate solution, it was extracted with ethyl acetate. The organic layer was washed sequentially with water and aqueous saturated sodium chloride solution, dried over anhydrous magnesium sulfate, and the solvent was removed under reduced pressure. The residue thus obtained was purified by silica gel column chromatography [Silica Gel; Fuji Silysia Chemical Ltd., Chromatorex-NH, eluent; chloroform:methanol=5:1], to give 400 mg of (1-(2-(4-((2,3-dihydro-1,4-benzodioxin-6-ylmethyl)amino)piperidin-1-yl)ethyl)-7-fluoroquinoxalin-2(1H)-one as a brown solid.

Provenance & Evidence