2,4-Dihydroxybenzaldehyde → 5-chloro-2,4-dihydroxybenzaldehyde

HRID 1797831Notes

Reaction equation

HRID 1797831 reaction equation
[Cl:1][O-].[Na+].N1CCCCC1.[OH:10][C:11]1[CH:18]=[C:17]([OH:19])[CH:16]=[CH:15][C:12]=1[CH:13]=[O:14]>S(=O)(=O)(O)O>[Cl:1][C:16]1[C:17]([OH:19])=[CH:18][C:11]([OH:10])=[C:12]([CH:15]=1)[CH:13]=[O:14]

Participants

5

Reactant 3

HCID 72132,4-DihydroxybenzaldehydeHCID 8082PiperidineHCID 23665760Sodium Hypochlorite

Product 1

HCID 147660725-chloro-2,4-dihydroxybenzaldehyde

Reagents, catalysts & solvents 1

HCID 1118Sulfuric AcidSolvent

Conditions

Temperature
0 °C

Procedure

Sodium hypochlorite (75 mL, 0.055 mol) and piperidine (4.68 g, 0.055 mol) were cooled to 0° C., combined cautiously and added dropwise over 2 h to a solution of 2,4,-dihydroxybenzaldehyde (6.91 g, 0.05 mol) in 50% aqueous sulfuric acid (150 mL) while cooling to 0° C. After three additional hours, the precipitate was collected via filtration in quantitative yield. 1H NMR indicates that it is about 65% 5-chloro-2,4-dihdroxybenzaldehyde, with the balance being 3-chloro-2,4-dihdroxybenzaldehyde. The product can be purified via column chromatography and/or repeated recrystallizations from toluene. However, the 3-chloro-2,4-dihdroxybenzaldehyde does not react in the next reaction, so the product was used without further purification.

Workup

  1. filtrationAfter three additional hours, the precipitate was collected via filtration in quantitative yield
  2. customThe product can be purified via column chromatography
  3. customrecrystallizations from toluene
  4. customHowever, the 3-chloro-2,4-dihdroxybenzaldehyde does not react in the next reaction, so the product
  5. customwas used without further purification

Sources & evidence

ORD record
ord-4cd12ff1a290470ca8ddb4b417eecb09
Source dataset
uspto-grants-2013_01
Patent number
US08343710B1

Reaction notes

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