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

HRID 973272Notes

Reaction equation

HRID 973272 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 abrown 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 abrown residue which
  6. customcrystallised from light petroleum (b.p. 40°-60° C)

Sources & evidence

ORD record
ord-8d18eee452f04faf9e16c5d59d3d5b70
Source dataset
uspto-grants-1977_10
Patent number
US04055654

Reaction notes

Loading…