Sulfuric Acid → 2-(4-Tert-butyl-benzoylamino)-4-hydroxy-benzoic acid methyl ester

HRID 1392261Notes

Reaction equation

HRID 1392261 reaction equation
[CH3:1][O:2][C:3](=[O:24])[C:4]1[CH:9]=[CH:8][C:7](N)=[CH:6][C:5]=1[NH:11][C:12](=[O:23])[C:13]1[CH:18]=[CH:17][C:16]([C:19]([CH3:22])([CH3:21])[CH3:20])=[CH:15][CH:14]=1.N([O-])=[O:26].[Na+].OS(O)(=O)=O>FC(F)(F)C(O)=O.O>[CH3:1][O:2][C:3](=[O:24])[C:4]1[CH:9]=[CH:8][C:7]([OH:26])=[CH:6][C:5]=1[NH:11][C:12](=[O:23])[C:13]1[CH:18]=[CH:17][C:16]([C:19]([CH3:22])([CH3:21])[CH3:20])=[CH:15][CH:14]=1

Participants

6

Reactant 3

HCID 1118Sulfuric AcidHCID 23668193Sodium NitriteHCID 691966714-Amino-2-(4-tert-butyl-benzoylamino)-benzoic acid methyl ester

Product 1

HCID 691962732-(4-Tert-butyl-benzoylamino)-4-hydroxy-benzoic acid methyl esterYield 71%

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 6422Trifluoroacetic acidSolvent

Procedure

To a solution of afford 4-amino-2-(4-tert-butyl-benzoylamino)-benzoic acid methyl ester (0.711 g, 2.18 mmol) in trifluoroacetic acid cooled to 0° C. was added NaNO2 (0.182 g, 2.64 mmol, 1.21 eq) as a solution in water (4 mL) and the reaction was stirred 5 minutes. It was then added dropwise to 30% solution of H2SO4 (50 mL) at 65° C. and stirred for 15 minutes. It was extracted with ethyl acetate, dried over MgSO4 and concentrated in vacuo. The residue was purified by flash chromatography using ethyl acetate/hexanes (20/80) to afford 2-(4-tert-butyl-benzoylamino)-4-hydroxy-benzoic acid methyl ester (0.508, 71%) as a white solid. mp=146.0-148.4° C.; mass spectrum (−ES, M−H) m/z 326. 1H NMR (400 MHz, DMSO-d6); δ 11.95 (bs, 1H), 10.60 (bs, 1H), 8.26 (d, 1H), 7.88 (m, 3H), 7.62 (d, 2H), 6.58 (dd, 1H), 3.85 (s, 3H), 1.32 (s, 9H). Elemental analysis: Calcd. for C19H21NO4: C, 69.71; H, 6.47; N, 4.28. Found: C, 69.20; H, 6.54; N, 4.17.

Workup

  1. stirringstirred for 15 minutes
  2. extractionIt was extracted with ethyl acetate
  3. dry with materialdried over MgSO4
  4. concentrationconcentrated in vacuo
  5. customThe residue was purified by flash chromatography

Sources & evidence

ORD record
ord-9ffa27713b6c4f3c880427eb8b965121
Source dataset
uspto-grants-2008_03
Patent number
US07342039B2

Reaction notes

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