Catechol → HCID 15042466, compound

HRID 346398Notes

Reaction equation

HRID 346398 reaction equation
[OH-].[Na+].[C:3]1([C:5](=[CH:7][CH:8]=[CH:9][CH:10]=1)[OH:6])O.[C:11]([OH:15])(=[O:14])[CH:12]=[O:13].Cl.[C:17](=[O:20])([O-])[O-].[I-].[CH2:22](Cl)[C:23]1[CH:28]=[CH:27][CH:26]=[CH:25][CH:24]=1>>[CH2:22]([O:6][C:5]1[CH:3]=[C:10]([CH:9]=[CH:8][C:7]=1[O:20][CH2:17][C:3]1[CH:5]=[CH:7][CH:8]=[CH:9][CH:10]=1)[CH:12]([OH:13])[C:11]([O:15][CH2:22][C:23]1[CH:28]=[CH:27][CH:26]=[CH:25][CH:24]=1)=[O:14])[C:23]1[CH:28]=[CH:27][CH:26]=[CH:25][CH:24]=1

Participants

8

Reactant 7

HCID 289Catechol2×HCID 313Hydrochloric AcidHCID 760Glyoxylic AcidHCID 7503Benzyl ChlorideHCID 14798Sodium HydroxideHCID 19660Carbonate IonHCID 30165Iodide Ion

Product 1

HCID 15042466HCID 15042466, compound

Conditions

Temperature
40 °C

Procedure

500 ml of an aqueous solution containing 48 g (1.2 mol) of sodium hydroxide was dropwise added to a suspension of 88 g (0.8 mol) of catechol and 109.5 g (about 0.5 mol) of a 40% glyoxylic acid aqueous solution under a nitrogen atmosphere under cooling with ice, and heated to 40° C. for 5 hours. The reaction solution was adjusted to pH2.0 with 6N hydrochloric acid under cooling with ice, and unreacted catechol was extracted with ethyl acetate. The water layer was evaporated to dryness under reduced pressure. The residue was dissolved in 700 ml of N,N-dimethylformamide and 276 g (2 mol) of pottasium carbonate, 10 g (60 mmol) of pottasium iodide and 230 ml (2 mol) of benzylchloride were added thereto. The mixture was stirred for 15 hours at room temperature and further stirred for 8 hours at 40° C. The reaction solution was poured into 1.5 liter of ice water and extracted with ethyl acetate, followed by washing with water and a saturated sodium chloride aqueous solution. The extract was dried over anhydrous sodium sulfate and concentrated under reduced pressure to obtain crude benzyl 3,4-dibenzyloxymandelate. 1 liter of methanol and 200 ml of an aqueous solution containing 60 g of sodium hydroxide were added to the residue and stirred for 5 hours at room temperature. The reaction solution was concentrated under reduced pressure, and 1 liter of ice water was added to the residue. The solution was adjusted to pH2.0 with concentrated hydrochloric acid and extracted with ethyl acetate. The extract was dried over anhydrous sodium sulfate and concentrated under reduced pressure. After cooling, the precipitated crystals were collected and washed with isopropyl ether to obtain 83 g (yield: 45.5%) of 3,4-dibenzyloxymandelic acid.

Workup

  1. temperatureunder cooling with ice
  2. extractionwas extracted with ethyl acetate
  3. customThe water layer was evaporated to dryness under reduced pressure
  4. dissolutionThe residue was dissolved in 700 ml of N,N-dimethylformamide
  5. stirringfurther stirred for 8 hours at 40° C
  6. extractionextracted with ethyl acetate
  7. washby washing with water
  8. dry with materialThe extract was dried over anhydrous sodium sulfate
  9. concentrationconcentrated under reduced pressure

Sources & evidence

ORD record
ord-0b9b071cc7734dff952e64c0b7e96632
Source dataset
uspto-grants-1991_10
Patent number
US05061794

Reaction notes

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