Dimethylformamide → 1-tert-butyl 3-methyl (2S,3S,5R)-5-hydroxy-2-[(4-phenyl-3,6-dihydropyridin-1(2H)-yl)carbonyl]piperidine-1,3-dicarboxylate

Participants

Reaction Steps

A mixture of (2S,3S,5R)-5-hydroxy-3-(methoxycarbonyl)piperidine-2-carboxylic acid (1.851 g, 0.009110 mol), 4-phenyl-1,2,3,6-tetrahydropyridine hydrochloride (2.14 g, 0.0109 mol) and benzotriazol-1-yloxytris(dimethylamino)phosphonium hexafluorophosphate (4.83 g, 0.0109 mol) in N,N-dimethylformamide (15.0 mL, 0.194 mol) was stirred at rt for 5 min, then treated with N,N-diisopropylethylamine (3.81 mL, 0.0219 mol) at rt for 2 h. The reaction mixture was diluted with methylene chloride (10.0 mL, 0.156 mol). The resultant mixture was then treated with N,N-diisopropylethylamine (3.17 mL, 0.0182 mol), followed by di-tert-butyldicarbonate (3.98 g, 0.0182 mol) at rt overnight. The reaction was diluted with water, extracted with EtOAc. The combined organic layers were washed with brine, dried, and concentrated to dry in vacuo. The residue was applied on silica gel, eluting with 0 to 80% EtOAc in hexane, to give the titled compound (2.10 g, 51.9%). MS (ESI): (M+H-Boc)+=345.1.

Provenance & Evidence