2,5-Dichlorophenol → 2,5-Dichloro-4-hydroxybenzaldehyde

HRID 1159383Notes

Reaction equation

HRID 1159383 reaction equation
[Cl:1][C:2]1[CH:7]=[CH:6][C:5]([Cl:8])=[CH:4][C:3]=1[OH:9].[OH-].[Ca+2].[OH-].[C:13](=O)([O-])[O-:14].[Na+].[Na+].Cl>O.C(Cl)(Cl)Cl>[Cl:8][C:5]1[CH:4]=[C:3]([OH:9])[C:2]([Cl:1])=[CH:7][C:6]=1[CH:13]=[O:14]

Participants

7

Reactant 4

HCID 662,5-DichlorophenolHCID 313Hydrochloric AcidHCID 10340Sodium CarbonateHCID 6093208Calcium Hydroxide

Product 1

HCID 5283812,5-Dichloro-4-hydroxybenzaldehydeYield 8%

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 6212ChloroformSolvent2×

Procedure

2,5-Dichlorophenol (CAS 583-78-8) (10 g, 0.060 mol), calcium hydroxide (19.5 g, 0.260 mol), and sodium carbonate (22.76 g, 0.220 mol) were suspended in water (140 mL). Chloroform (14.6 g, 0.120 mol) was added for 30 min, and the mixture was refluxed under vigorous stirring for 2 h. The reaction mixture was cooled on ice bath. Concentrated HCl (80 mL) and chloroform (200 mL) were added. The aqueous layer was discarded. The organic one was dried with anhydrous Na2SO4 (10 g) and evaporated in vacuo. The residue was purified by chromatography (silica gel 63-100 μm, 150 g, CCl4→CCl4:EtOAc (60:40)). Fractions containing the product were combined, evaporated to give the title compound (0.88 g, 4.60 mmol, 8%) as yellow crystals. 1H NMR data (DMSO-d6): 11.95 (s, 1H, COH); 10.09 (s, 1H, OH); 7.83 (s, 1H, Ar—H); 7.09 (s, 1H, Ar—H).

Workup

  1. temperaturethe mixture was refluxed
  2. temperatureThe reaction mixture was cooled on ice bath
  3. dry with materialThe organic one was dried with anhydrous Na2SO4 (10 g)
  4. customevaporated in vacuo
  5. customThe residue was purified by chromatography (silica gel 63-100 μm, 150 g, CCl4→CCl4:EtOAc (60:40))
  6. additionFractions containing the product
  7. customevaporated

Sources & evidence

ORD record
ord-b29034434dd44d50ab768fe158b26850
Source dataset
uspto-grants-2010_10
Patent number
US07812040B2

Reaction notes

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