Ethylene Glycol → 5-Benzyloxy-2,2-dimethyl-7-(1,1-dimethylheptyl)-3,4-dihydro-2H-benzopyran-4-carboxylic acid

HRID 2118920Notes

Reaction equation

HRID 2118920 reaction equation
[CH2:1]([O:8][C:9]1[C:14]2C(C#N)[CH2:16][C:17]([CH3:20])([CH3:19])[O:18][C:13]=2[CH:12]=[C:11]([C:23]([CH3:31])([CH3:30])[CH2:24][CH2:25][CH2:26][CH2:27][CH2:28][CH3:29])[CH:10]=1)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.[OH-:32].[K+].[CH2:34]([OH:37])[CH2:35]O.Cl>C(OCC)C>[CH2:1]([O:8][C:9]1[C:14]2[CH:35]([C:34]([OH:37])=[O:32])[CH2:16][C:17]([CH3:20])([CH3:19])[O:18][C:13]=2[CH:12]=[C:11]([C:23]([CH3:31])([CH3:30])[CH2:24][CH2:25][CH2:26][CH2:27][CH2:28][CH3:29])[CH:10]=1)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1

Participants

6

Reactant 4

HCID 174Ethylene GlycolHCID 313Hydrochloric AcidHCID 14797Potassium HydroxideHCID 133645735-benzyloxy-4-cyano-2,2-dimethyl-7-(1,1-dimethylheptyl)-3,4-dihydro-2H-benzopyran

Product 1

HCID 133645785-Benzyloxy-2,2-dimethyl-7-(1,1-dimethylheptyl)-3,4-dihydro-2H-benzopyran-4-carboxylic acid

Reagents, catalysts & solvents 1

HCID 3283Diethyl EtherSolvent

Procedure

A mixture of 2.0 g 5-benzyloxy-4-cyano-2,2-dimethyl-7-(1,1-dimethylheptyl)-3,4-dihydro-2H-benzopyran, 20 g potassium hydroxide and 100 ml ethylene glycol are heated under nitrogen at reflux for 18 hours and cooled to ambient temperature. The mixture is acidified to pH 3 with concentrated hydrochloric acid, extracted with ethyl acetate and the extracts dried (MgSO4). Evaporation of solvent gives an oil which is taken up in ethyl ether, washed with water, brine, dried (MgSO4) and the solvent evaporated to give 2.09 g of crude solid. The crude was purified by chromatography on silica gel, eluting with ethyl ether/hexane. The combined product fractions are combined and solvent evaporated to afford 1.69 g of product, m.p. 137°-138° C.

Workup

  1. temperatureare heated under nitrogen
  2. temperatureat reflux for 18 hours
  3. extractionextracted with ethyl acetate
  4. dry with materialthe extracts dried (MgSO4)
  5. customEvaporation of solvent
  6. customgives an oil which
  7. washwashed with water, brine
  8. dry with materialdried (MgSO4)
  9. customthe solvent evaporated
  10. customto give 2.09 g of crude solid
  11. customThe crude was purified by chromatography on silica gel
  12. washeluting with ethyl ether/hexane
  13. customsolvent evaporated

Sources & evidence

ORD record
ord-68868213a62b4bb49989478c0a4e6d77
Source dataset
uspto-grants-1987_07
Patent number
US04680404

Reaction notes

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