Trifluoroacetic acid → Hexahydropyrazino[2,1-c][1,4]thiazin-9(6H)-one 2,2-dioxide

Participants

Reaction Steps

To a solution of methyl 4-[2-({[(1,1-dimethylethyl)oxy]carbonyl}amino)ethyl]-3-thiomorpholinecarboxylate 1,1-dioxide (D17; 295 mg, 0.88 mmol) in 3 ml of anhydrous dichloromethane was added 1 ml of trifluoroacetic acid and the resulting solution was stirred at room temperature under nitrogen for 1 h 30 min. The solvent was removed under reduced pressure and the residue loaded on a SCX column, washed with methanol and eluted with methanolic ammonia. The product was purified further by chromatography (silica cartridge, cyclohexane to ethyl acetate, then dichloromethane to dichloromethane:methanol 70:30) to give 165 mg of the target compound.

Provenance & Evidence