Benzyl chloroformate → 4-Benzyloxycarbonylamino-1-t-butyloxycarbonyl-3,3-dimethylpiperidine

Participants

Reaction Conditions

Reaction Steps

Benzyl chloroformate (50% in toluene, 450 ml, 1.57 mol) was added to a stirred suspension of 4-amino-1-t-butyloxycarbonyl-3,3-dimethylpiperidine (365 g) as prepared above and NaHCO3 (150 g, 1.78 mol) in dry tetrahydrofuran (1.5 L). The reaction mixture was stirred for 20 hr at 35° C. The reaction mixture was diluted with 3.5 L water and was extracted with 2.0 L×2 ethyl acetate. Combined organic extract was washed with water, dried over Na2SO4 and concentrated to dryness. The residue was subjected to chromatography on a silica gel column to give 4-benzyloxycarbonylamino-1-t-butyloxycarbonyl-3,3-dimethylpiperidine in 63% (350 g) yield. m/z 363 (M+1).

Provenance & Evidence