Citric Acid → (2R,4S)-2-methyl-4-((2-methylpropan-2-yl)oxycarbonylamino)-5-(4-phenylphenyl)pentanoic acid

HRID 1021060Notes

Reaction equation

HRID 1021060 reaction equation
[C:1]1([C:23]2[CH:28]=[CH:27][CH:26]=[CH:25][CH:24]=2)[CH:6]=[CH:5][C:4]([CH2:7][C@@H:8]([NH:15][C:16]([O:18][C:19]([CH3:22])([CH3:21])[CH3:20])=[O:17])[CH2:9][C@@H:10]([CH3:14])[C:11]([OH:13])=[O:12])=[CH:3][CH:2]=1.[C:29](Cl)(=O)[C:30]([CH3:33])(C)[CH3:31].[CH2:36](N(CC)CC)[CH3:37].C(O)(=O)CC(CC(O)=O)(C(O)=O)O>C(OC(C)C)(=O)C.O>[CH2:36]([O:13][C:11](=[O:12])[C@H:10]([CH3:14])[CH2:9][C@H:8]([NH:15][C:16](=[O:18])[C:30]([CH3:33])([CH3:31])[CH3:29])[CH2:7][C:4]1[CH:5]=[CH:6][C:1]([C:23]2[CH:28]=[CH:27][CH:26]=[CH:25][CH:24]=2)=[CH:2][CH:3]=1)[CH3:37].[C:1]1([C:23]2[CH:24]=[CH:25][CH:26]=[CH:27][CH:28]=2)[CH:2]=[CH:3][C:4]([CH2:7][C@@H:8]([NH:15][C:16]([O:18][C:19]([CH3:22])([CH3:20])[CH3:21])=[O:17])[CH2:9][C@@H:10]([CH3:14])[C:11]([OH:13])=[O:12])=[CH:5][CH:6]=1

Participants

8

Reactant 4

HCID 311Citric AcidHCID 8471TriethylamineHCID 62493Pivaloyl chlorideHCID 46193546(2R,4S)-2-methyl-4-((2-methylpropan-2-yl)oxycarbonylamino)-5-(4-phenylphenyl)pentanoic acid

Product 2

HCID 46193546(2R,4S)-2-methyl-4-((2-methylpropan-2-yl)oxycarbonylamino)-5-(4-phenylphenyl)pentanoic acidHCID 66739227HCID 66739227, compound

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 7915Isopropyl AcetateSolvent3×

Procedure

10 g (2S,4S)-4-amino-5-biphenyl-4-yl-2-methylpentanoic acid ethyl ester hydrochloride (3-a, R1=R2=1-1, R3=Et) in isopropyl acetate (50 ml) is added to a mixture of pivaloyl chloride (4.1 ml) in isopropyl acetate (50 ml). The mixture is then stirred for 40 min at room temperature. Triethylamine (10.3 ml) in isopropyl acetate (30 ml) is then added over a period of 1 h. The resulting mixture is stirred for 16 h. Citric acid (7.5 g) dissolved in water (30 ml) is added and the phases are separated. The organic phase is washed twice with water (30 ml) and concentrated in vacuo to give (2R,4S)-5-Biphenyl-4-yl-4-(2,2-dimethylpropionylamino)-2-methylpentanoic acid ethyl ester (3-a, R1=Piv, R2=H, R3=Et). 1H NMR (DMSO): 1.05 (9H), 1.09 (3H), 1.15 (3H), 1.54 (1H), 1.78 (1H), 2.48 (1H), 2.72 (2H), 3.97 (1H), 4.00 (2H), 7.15 (1H), 7.25 (2H), 7.34 (1H), 7.45 (2H), 7.55 (2H), 7.62 (2H).

Workup

  1. stirringThe resulting mixture is stirred for 16 h
  2. additionis added
  3. customthe phases are separated
  4. washThe organic phase is washed twice with water (30 ml)
  5. concentrationconcentrated in vacuo

Sources & evidence

ORD record
ord-832ba240f8d343969fd493c3a799856d
Source dataset
uspto-grants-2014_05
Patent number
US08716495B2

Reaction notes

Loading…