Triphosgene → Hexahydropyrazino[1,2-c][1,3]oxazin-6(2H)-one

Participants

Reaction Steps

3-(2-Hydroxy-ethyl)-piperazine-1-carboxylic acid tert-butyl ester (58 mg, 0.25 mmol) was dissolved in 4 mL of dichloromethane and 1 mL of DIPEA, and then triphosgene (27 mg, 0.09 mmol) was added at room temperature. The reaction mixture was stirred for 30 minutes, and the solvent was removed in vacuo. The residue was dissolved in 3 mL of dichloromethane and 1 mL of TFA. After the reaction mixture was stirred for 1 hour, the solvent was removed in vacuo to give hexahydro-pyrazino[1,2-c][1,3]oxazin-6-one trifluoro acetitic acid salt (Compound D) as a crude product which was used directly without further purification. LC/MS: calc'd 157 (MH+), exp 157 (MH+).

Provenance & Evidence