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

HRID 41386Notes

Reaction equation

HRID 41386 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

Reactant 3

HCID 14798Sodium HydroxideHCID 24408BromineHCID 247734531-(2,4-Bis-benzyloxy-5-tert-butyl-phenyl)-ethanone

Product 1

HCID 469156392,4-Bis-benzyloxy-5-tert-butyl-benzoic acidYield 79%

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 312751,4-DioxaneSolvent

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-b8b38b34f9f7471c96a6178bf2f84b7e
Source dataset
uspto-grants-2013_09
Patent number
US08530469B2

Reaction notes

Loading…