Sodium Hydroxide → 2,4-Bis-benzyloxy-5-tert-butyl-benzoic acid

HRID 334885Notes

Reaction equation

HRID 334885 reaction equation
[CH2:1]([O:8][C:9]1[CH:14]=[C:13]([O:15][CH2:16][C:17]2[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=2)[C:12]([C:23]([CH3:26])([CH3:25])[CH3:24])=[CH:11][C:10]=1[C:27](=[O:29])C)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.[OH-:30].[Na+].BrBr>O1CCOCC1.O>[CH2:1]([O:8][C:9]1[CH:14]=[C:13]([O:15][CH2:16][C:17]2[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=2)[C:12]([C:23]([CH3:24])([CH3:26])[CH3:25])=[CH:11][C:10]=1[C:27]([OH:29])=[O:30])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1

Participants

6

Procedure

1-(2,4-Bis-benzyloxy-5-tert-butyl-phenyl)-ethanone [prepared as per WO 2004/072051] (2.02 g, 5.2 mmol) was dissolved in 1,4-dioxane (30 ml), a solution of sodium hydroxide (2.08 g, 52.0 mmol) in water (30 ml) was added and the mixture was stirred and treated dropwise with bromine (0.8 ml, 15.6 mmol). The resulting mixture was stirred at room temperature for 16 hours. The 1,4-dioxane was removed in vacuo and the mixture acidified to pH 2 or below by the addition of 2M hydrochloric acid. The mixture was extracted with ethyl acetate, the organic layer was separated, the solvent removed in vacuo and the residue subjected to column chromatography on silica. Elution with 30% ethyl acetate in petroleum ether afforded 2,4-bis-benzyloxy-5-tert-butyl-benzoic acid (1.6 g, 79%) as a pale yellow oil. 1H NMR (DMSO-d6) 12.18 (1H, br s), 7.69 (1H, s), 7.52 (4H, t), 7.45-7.33 (6H, m), 6.93 (1H, s), 5.24 (2H, s), 5.23 (2H, s), 1.32 (9H, s). MS: [M+H]+ 391.

Workup

  1. stirringThe resulting mixture was stirred at room temperature for 16 hours
  2. customThe 1,4-dioxane was removed in vacuo
  3. additionthe mixture acidified to pH 2 or below by the addition of 2M hydrochloric acid
  4. extractionThe mixture was extracted with ethyl acetate
  5. customthe organic layer was separated
  6. customthe solvent removed in vacuo
  7. washElution with 30% ethyl acetate in petroleum ether

Sources & evidence

ORD record
ord-fe0e836fdcec4b80ab7481d515e5d6ef
Source dataset
uspto-grants-2014_11
Patent number
US08883790B2

Reaction notes

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