Sodium borohydride → (3R,4R)-benzyl 3-amino-4-(tosyloxy)piperidine-1-carboxylate
Reaction equation
[BH4-].[Na+].[N:3]([C@H:6]1[C@H:11]([O:12][S:13]([C:16]2[CH:22]=[CH:21][C:19]([CH3:20])=[CH:18][CH:17]=2)(=[O:15])=[O:14])[CH2:10][CH2:9][N:8]([C:23]([O:25][CH2:26][C:27]2[CH:32]=[CH:31][CH:30]=[CH:29][CH:28]=2)=[O:24])[CH2:7]1)=[N+]=[N-]>CO>[NH2:3][C@H:6]1[C@H:11]([O:12][S:13]([C:16]2[CH:17]=[CH:18][C:19]([CH3:20])=[CH:21][CH:22]=2)(=[O:14])=[O:15])[CH2:10][CH2:9][N:8]([C:23]([O:25][CH2:26][C:27]2[CH:28]=[CH:29][CH:30]=[CH:31][CH:32]=2)=[O:24])[CH2:7]1Participants
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
To a cooled (0° C., ice/water bath) solution of CuSO4.5H2O (642 mg, 0.5 equiv) in methanol (30 mL) was added slowly NaBH4 (200 mg, 1.05 equiv). To the stirred black suspension was added a solution of (3R,4R)-benzyl 3-azido-4-(tosyloxy)piperidine-1-carboxylate (2.21 g, 5.14 mmol) in methanol (20 mL). Additional NaBH4 (578 mg, 3 equiv) was introduced into the reaction in four portions over the course of 1 h. LC-MS showed the reaction was complete. The reaction mixture was filtered through a pad of Celite, and concentrated. The residue was diluted with CH2Cl2 (70 mL), washed with water (15 mL), satd aq NH4Cl solution (2×10 mL) and brine (15 mL), and dried over Na2SO4. Concentration afforded (3R,4R)-benzyl 3-amino-4-(tosyloxy)piperidine-1-carboxylate (1.34 g, 64%). LC-MS (3 min) tR=1.26 min., m/z 405 (M+1). The product was used for the next step without further purification.
Workup
- filtrationThe reaction mixture was filtered through a pad of Celite
- concentrationconcentrated
- additionThe residue was diluted with CH2Cl2 (70 mL)
- washwashed with water (15 mL)
- dry with materialdried over Na2SO4
- concentrationConcentration
Sources & evidence
- ORD record
- ord-c6b6921da89043ee8178665c387f45f6
- Source dataset
- uspto-grants-2013_06
- Patent number
- US08455521B2
Reaction notes
Loading…