Ammonium formate → t-butyl (2S)-2-(n-butylsulphonylamino)-3-(4-aminophenyl)propionate

HRID 1900885Notes

Reaction equation

HRID 1900885 reaction equation
[CH2:1]([S:5]([NH:8][C@@H:9]([CH2:17][C:18]1[CH:23]=[CH:22][C:21]([N+:24]([O-])=O)=[CH:20][CH:19]=1)[C:10]([O:12][C:13]([CH3:16])([CH3:15])[CH3:14])=[O:11])(=[O:7])=[O:6])[CH2:2][CH2:3][CH3:4].C([O-])=O.[NH4+]>CO.[Pd]>[CH2:1]([S:5]([NH:8][C@@H:9]([CH2:17][C:18]1[CH:19]=[CH:20][C:21]([NH2:24])=[CH:22][CH:23]=1)[C:10]([O:12][C:13]([CH3:15])([CH3:16])[CH3:14])=[O:11])(=[O:6])=[O:7])[CH2:2][CH2:3][CH3:4]

Participants

5

Reactant 2

HCID 2723923Ammonium formateHCID 57310062t-butyl (2S)-2-(n-butylsulphonylamino)-3-(4-nitrophenyl)propionate

Product 1

HCID 57133224t-butyl (2S)-2-(n-butylsulphonylamino)-3-(4-aminophenyl)propionateYield 96.8%

Reagents, catalysts & solvents 2

HCID 23938PalladiumCatalystHCID 887MethanolSolvent

Procedure

To a solution of the product of step (b) (2.9 g) and ammonium formate (1.90 g) in methanol (30 ml) under argon was added 10% Pd on C (450 mg). The reaction mixture was stirred at ambient temperature for 6 hours then the catalyst was filtered off using a pad of diatomaceous earth which was washed with methanol (30 ml). The combined filtrate and washings were evaporated to dryness and the residue was partitioned between ethyl acetate (50 ml) and dilute NaHCO3 (aq.) (50 ml). The organic layer was separated, washed with water, dried (MgSO4) and evaporated to yield a residue which slowly solidified to give t-butyl (2S)-2-(n-butylsulphonylamino)-3-(4-aminophenyl)propionate (2.59 g) as an off-white solid: NMR Spectrum (CDCl3) 0.90 (3H, t), 1.36 (2H, m), 1.45 (9H, s), 1.67 (2H, m), 2.77 (2H, m), 2.93 (2H, m), 3.62 (2H, br s), 4.16 (1H, m), 4.68 (1H, d), 6.61 (2H, d), 6.99 (2H, d); Mass Spectrum m/Z 379 (M+Na)+.

Workup

  1. filtrationthe catalyst was filtered off
  2. washwas washed with methanol (30 ml)
  3. customThe combined filtrate and washings were evaporated to dryness
  4. customthe residue was partitioned between ethyl acetate (50 ml) and dilute NaHCO3 (aq.) (50 ml)
  5. customThe organic layer was separated
  6. washwashed with water
  7. dry with materialdried (MgSO4)
  8. customevaporated
  9. customto yield a residue which

Sources & evidence

ORD record
ord-0e415301884f450d920e3f506085f951
Source dataset
uspto-grants-1996_11
Patent number
US05576334

Reaction notes

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