Selenium Dioxide → 6,8-di-t-butyl-4-oxo-4H-1-benzopyran-2-carboxylic acid, ethyl ester

HRID 1606327Notes

Reaction equation

HRID 1606327 reaction equation
[C:1]([C:5]1[CH:6]=[C:7]([C:21]([CH3:24])([CH3:23])[CH3:22])[C:8]2[O:13][CH:12]([C:14]([O:16][CH2:17][CH3:18])=[O:15])[CH2:11][C:10](=[O:19])[C:9]=2[CH:20]=1)([CH3:4])([CH3:3])[CH3:2].[Se](=O)=O>CCOCC>[C:1]([C:5]1[CH:6]=[C:7]([C:21]([CH3:22])([CH3:24])[CH3:23])[C:8]2[O:13][C:12]([C:14]([O:16][CH2:17][CH3:18])=[O:15])=[CH:11][C:10](=[O:19])[C:9]=2[CH:20]=1)([CH3:4])([CH3:3])[CH3:2]

Participants

4

Reactant 2

HCID 24007Selenium DioxideHCID 867332766,8-di-t-butyl-2,3-dihydro-4-oxo-4H-1-benzopyran-2-carboxylic acid, ethyl ester

Product 1

HCID 538439426,8-di-t-butyl-4-oxo-4H-1-benzopyran-2-carboxylic acid, ethyl ester

Reagents, catalysts & solvents 1

HCID 3283Diethyl EtherSolvent

Procedure

A mixture of 3.32 parts of 6,8-di-t-butyl-2,3-dihydro-4-oxo-4H-1-benzopyran-2-carboxylic acid, ethyl ester and 3.33 parts of selenium dioxide was refluxed in 35 parts of xlene for eight hours. The reaction mixture was cooled, ether was added and the insoluble inorganic products were removed by filtration. Evaporation of the volatile components of the filtrate gave a brown residue which crystallised from light petroleum (b.p. 40°-60°C) to give 1.54 parts of 6,8-di-t-butyl-4-oxo-4H-1-benzopyran-2-carboxylic acid, ethyl ester, m.p. 130°-131.5°C.

Workup

  1. temperaturewas refluxed in 35 parts of xlene for eight hours
  2. temperatureThe reaction mixture was cooled
  3. customthe insoluble inorganic products were removed by filtration
  4. customEvaporation of the volatile components of the filtrate
  5. customgave a brown residue which
  6. customcrystallised from light petroleum (b.p. 40°-60°C)

Sources & evidence

ORD record
ord-ec7c54b1a57140d1aaa4df6e394ae49b
Source dataset
uspto-grants-1976_04
Patent number
US03952104

Reaction notes

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