2,3-Dichloro-5,6-dicyano-1,4-benzoquinone → HCID 22010257, compound

HRID 322873Notes

Reaction equation

HRID 322873 reaction equation
[CH2:1]([O:8][C:9]1[CH:10]=[C:11]([C:25](=[O:40])[CH:26]([C:33]2[CH:38]=[CH:37][CH:36]=[CH:35][C:34]=2[CH3:39])[CH2:27][CH2:28][C:29]([O:31]C)=[O:30])[CH:12]=[C:13]([O:15]CC2C=CC(OC)=CC=2)[CH:14]=1)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.ClC1C(=O)C(C#N)=C(C#N)C(=O)C=1Cl>ClCCl.P([O-])([O-])([O-])=O.C(O)(C)(C)C.O>[CH2:1]([O:8][C:9]1[CH:10]=[C:11]([C:25](=[O:40])[CH:26]([C:33]2[CH:38]=[CH:37][CH:36]=[CH:35][C:34]=2[CH3:39])[CH2:27][CH2:28][C:29]([OH:31])=[O:30])[CH:12]=[C:13]([OH:15])[CH:14]=1)[C:2]1[CH:3]=[CH:4][CH:5]=[CH:6][CH:7]=1

Participants

7

Reactant 2

HCID 67752,3-Dichloro-5,6-dicyano-1,4-benzoquinoneHCID 86756582HCID 86756582, compound

Product 1

HCID 22010257HCID 22010257, compound

Reagents, catalysts & solvents 4

HCID 962WaterSolventHCID 1061PhosphateSolventHCID 6344DichloromethaneSolventHCID 6386tert-ButanolSolvent

Procedure

A solution of methyl (RS)-5-[3-benzyloxy-5-(4-methoxybenzyloxy)phenyl]-4-(2-methylphenyl)-5-oxopentanoate (0.54 g) in dichloromethane (10 mL), pH 7.3 phosphate buffer and tert-butanol (0.1 mL) is treated at 0° C. with 2,3-dichloro-5,6-dicyanobenzoquinone (0.34 g) and stirred at ambient temperature for 48 hours. It is then diluted with water (100 mL) and extracted with dichloromethane (3×30 mL). The combined organic extracts are washed with brine (50 mL), dried over magnesium sulphate and concentrated. The resulting oil (0.4 g) is dissolved in a solution of potassium hydroxide in methanol (20 mL; 15% w/v) and heated at reflux for 5 hours and is then allowed to cool. The mixture is concentrated, diluted with water (30 mL) and acidified to pH1 by treatment with concentrated hydrochloric acid. The mixture is extracted with ethyl acetate (3×50 mL) and the combined organic extracts are washed with brine and dried over magnesium sulphate, and concentrated. The resulting residue is chromatographed on silica gel, eluting with a mixture of ethyl acetate and pentane (1:1 v/v). The resulting oil is triturated with a mixture of diisopropyl ether and pentane, to give (RS)-5-(3-benzyloxy-5-hydroxyphenyl)-4-(2-methylphenyl)-5-oxopentanoic acid in the form of a white solid (80 mg), m.p. 116-117° C. [Elemental analysis:- C,73.80; H,5.90%; Calculated:- C,74.24;H,5.98%].

Workup

  1. extractionextracted with dichloromethane (3×30 mL)
  2. washThe combined organic extracts are washed with brine (50 mL)
  3. dry with materialdried over magnesium sulphate
  4. concentrationconcentrated
  5. dissolutionThe resulting oil (0.4 g) is dissolved in a solution of potassium hydroxide in methanol (20 mL; 15% w/v)
  6. temperatureheated
  7. temperatureat reflux for 5 hours
  8. temperatureto cool
  9. concentrationThe mixture is concentrated
  10. additiondiluted with water (30 mL)
  11. extractionThe mixture is extracted with ethyl acetate (3×50 mL)
  12. washthe combined organic extracts are washed with brine
  13. dry with materialdried over magnesium sulphate
  14. concentrationconcentrated
  15. customThe resulting residue is chromatographed on silica gel
  16. washeluting with a mixture of ethyl acetate and pentane (1:1 v/v)
  17. customThe resulting oil is triturated with a mixture of diisopropyl ether and pentane

Sources & evidence

ORD record
ord-8639d02a4ce64bc68df3ca85754c29ae
Source dataset
uspto-grants-2001_04
Patent number
US06211234B1

Reaction notes

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