Benzyl Bromide → 4-Benzyloxy-3-hydroxybenzaldehyde

HRID 2213568Notes

Reaction equation

HRID 2213568 reaction equation
[CH2:1](Br)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.[OH:9][C:10]1[CH:11]=[C:12]([CH:15]=[CH:16][C:17]=1[OH:18])[CH:13]=[O:14].C(=O)([O-])[O-].[Cs+].[Cs+]>[I-].C([N+](CCCC)(CCCC)CCCC)CCC.CN(C)C=O>[OH:9][C:10]1[CH:11]=[C:12]([CH:15]=[CH:16][C:17]=1[O:18][CH2:1][C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1)[CH:13]=[O:14]

Participants

6

Reactant 3

HCID 7498Benzyl BromideHCID 87683,4-DihydroxybenzaldehydeHCID 10796Cesium carbonate

Product 1

HCID 5613694-Benzyloxy-3-hydroxybenzaldehydeYield 52.6%

Reagents, catalysts & solvents 2

HCID 67553Tetrabutylammonium IodideCatalystHCID 6228DimethylformamideSolvent

Procedure

Benzyl bromide (9 mL, 0.073 mol, 1.05 eq) was added to a stirred solution of 3,4-dihydroxybenzaldehyde (10 g, 0.07 mol, 1 eq), tetra-n-butylammonium iodide (29.4 g, 0.077 mol, 1.1 eq) and cesium carbonate (24.8 g, 0.073 mol, 1.05 eq) in N,N-dimethylformamide (200 mL). The reaction mixture was stirred overnight, and then concentrated in vacuo. The residual solution was diluted with ethyl acetate (200 mL) and washed with water (2×200 mL). The organic solution was then extracted with 0.5M aqueous sodium hydroxide (5×200 mL), and the basic extracts combined and washed with ethyl acetate (400 mL), then acidified to pH 1 with concentrated HCl and back extracted with ethyl acetate (2×300 mL). The organic extracts were combined, washed with brine (200 mL), dried over sodium sulfate and evaporated in vacuo. This gave a gummy solid, which was recrystallized from ethyl acetate and petroleum ether to give the product as a brown powder (8.4 g, 51%). 1H NMR (CDCl3) δ 9.84 (s, 1H, O═C—H), 5.84 (s, 1H, OH), 5.21 (s, 2H, CH2Ph).

Workup

  1. concentrationconcentrated in vacuo
  2. additionThe residual solution was diluted with ethyl acetate (200 mL)
  3. washwashed with water (2×200 mL)
  4. extractionThe organic solution was then extracted with 0.5M aqueous sodium hydroxide (5×200 mL)
  5. washwashed with ethyl acetate (400 mL)
  6. extractionback extracted with ethyl acetate (2×300 mL)
  7. washwashed with brine (200 mL)
  8. dry with materialdried over sodium sulfate
  9. customevaporated in vacuo
  10. customThis gave a gummy solid, which
  11. customwas recrystallized from ethyl acetate and petroleum ether

Sources & evidence

ORD record
ord-42c51cac75734bb5800b6629bc0ebd72
Source dataset
uspto-grants-2006_09
Patent number
US07105554B2

Reaction notes

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