Sodium Carbonate → HCID 69095725, compound

Participants

Reaction Conditions

Reaction Steps

A cooled (0° C.) solution of tert-butyl 3-(2,6-dimethoxyphenyl)-2,5-dioxo-4-(4-(trifluoromethoxy)benzyl)piperazine-1-carboxylate (718 mg; 1.36 mmol) in anh. MeOH (15 ml) was treated with NaBH4 (221 mg; 5.47 mmol), and stirring at 0° C., under nitrogen, was continued for 30 min. After concentration to dryness under reduced pressure, the residue was dissolved in AcOEt, and washed successively with 1 M aq. HCl and brine. The separated aq. layer was further extracted with AcOEt (3×10 ml), and the mixed organic layers were dried over anh. MgSO4, filtered, and concentrated to dryness under reduced pressure. Acetic acid (20 ml) was added, and the cooled (0° C.) mixture was then treated portionwise with NaBH3CN (516 mg; 8.21 mmol). The resulting mixture was further stirred at rt, under nitrogen, for 1 h. DCM and aq. sat. Na2CO3 were then added, and the separated aq. layer was further extracted with DCM. The mixed organic layers were then dried over anh. MgSO4, filtered, and concentrated to dryness under reduced pressure. Purification by FC (DCM/MeOH=25/1) afforded tert-butyl 3-(2,6-dimethoxyphenyl)-5-oxo-4-(4-(trifluoromethoxy)benzyl)piperazine-1-carboxylate as an orange oil. LC-MS (conditions D): tR=1.12 min.; [M+H]+: 511.01 g/mol.

Provenance & Evidence