2-(2-Bromo-6-methyl-4-nitrophenyl)-2-tert-butoxyethyl pivalate → (S)-2-(4-amino-2-bromo-6-methylphenyl)-2-tert-butoxyethyl pivalate
Reaction equation
[C:1]([O:7][CH2:8][CH:9]([C:15]1[C:20]([CH3:21])=[CH:19][C:18]([N+:22]([O-])=O)=[CH:17][C:16]=1[Br:25])[O:10][C:11]([CH3:14])([CH3:13])[CH3:12])(=[O:6])[C:2]([CH3:5])([CH3:4])[CH3:3]>CCO.CCOC(C)=O.[Pt]>[C:1]([O:7][CH2:8][C@H:9]([C:15]1[C:20]([CH3:21])=[CH:19][C:18]([NH2:22])=[CH:17][C:16]=1[Br:25])[O:10][C:11]([CH3:12])([CH3:13])[CH3:14])(=[O:6])[C:2]([CH3:3])([CH3:4])[CH3:5]Participants
Procedure
To a solution of S)-2-(2-bromo-6-methyl-4-nitrophenyl)-2-tert-butoxyethyl pivalate (9 g, 21.63 mmol) in EtOH (50 ml) and EtOAc (50 ml) was added Pt/C (1.5 g), attached with a balloon of H2. More Pt/C (500 mg) was added after 3 h. Then the reaction mixture was stirred at rt for another 2 h. The reaction mixture was filtered over celite, concentrated down to give product (S)-2-(4-amino-2-bromo-6-methylphenyl)-2-tert-butoxyethyl pivalate (65G) and went to next step without purification. To a solution of (S)-2-(4-amino-2-bromo-6-methylphenyl)-2-tert-butoxyethyl pivalate (65G) (21.63 mmol) in HOAc/THF (80 ml, 1:1) was added KSCN at 0° C. The reaction mixture was stirred at 0° C. for 0.5 h. Then Br2 was added slowly, reacted at 0° C. The reaction was quenched by adding sat. NaHSO3, extracted by EtOAc, dried over MgSO4, purified by silica gel column, eluting by 0-40% EtOAc in Hexanes to give 65H (2.3 g, 24% over 2 steps).
Workup
- filtrationThe reaction mixture was filtered over celite
- concentrationconcentrated down
Sources & evidence
- ORD record
- ord-444b0125156d406ea04ce50cf7bed721
- Source dataset
- uspto-grants-2015_04
- Patent number
- US09006229B2
Reaction notes
Loading…