Methane → HCID 353996, compound

HRID 1194465Notes

Reaction equation

HRID 1194465 reaction equation
[OH:1][C:2]1[C:3]([OH:23])=[CH:4][C:5]2[O:10][CH:9]=[C:8]([C:11]3[CH:16]=[CH:15][C:14]([O:17][CH3:18])=[C:13]([O:19][CH3:20])[CH:12]=3)[C:7](=O)[C:6]=2[CH:22]=1.C.OS(O)(=O)=O>O1CCOCC1.C(O)C.[Pd]>[OH:1][C:2]1[C:3]([OH:23])=[CH:4][C:5]2[O:10][CH2:9][CH:8]([C:11]3[CH:16]=[CH:15][C:14]([O:17][CH3:18])=[C:13]([O:19][CH3:20])[CH:12]=3)[CH2:7][C:6]=2[CH:22]=1

Participants

7

Reactant 3

HCID 297MethaneHCID 1118Sulfuric AcidHCID 21270169HCID 21270169, compound

Product 1

HCID 353996HCID 353996, compound

Reagents, catalysts & solvents 3

HCID 23938PalladiumCatalystHCID 702EthanolSolventHCID 312751,4-DioxaneSolvent

Procedure

6,7-Dihydroxy-3-(3,4-dimethoxyphenyl)-4H-1-benzopyran-4-one [Indian J. Chem. Sect. B 19B, 82 (1980) and Indian J. Chem. Sect. B 15B, 1049 (1977)] (25 g) in a mixture of dioxane and ethanol 1:1 (1250 ml) is hydrogenated for 8 days at normal pressure and room temperature over palladium 10% on active charcoal (2.5 g) in the presence of concentrated H2SO4 (2.5 ml). After filtration of the catalyst, the filtrate is evaporated under reduced pressure to a volume of about 50 ml and diluted with water till turbidity appears. After cooling the solution, a solid precipitates. It is filtered off and recrystallized from ethanol. The product is dried in vacuo to constant weight to yield 3,4-dihydro-6,7-dihydroxy-3-(3,4-dimethoxyphenyl)-2H-1-benzopyran, m.p. 153°.

Workup

  1. filtrationAfter filtration of the catalyst
  2. customthe filtrate is evaporated under reduced pressure to a volume of about 50 ml
  3. additiondiluted with water till turbidity
  4. temperatureAfter cooling the solution
  5. customa solid precipitates
  6. filtrationIt is filtered off
  7. customrecrystallized from ethanol
  8. customThe product is dried in vacuo to constant weight

Sources & evidence

ORD record
ord-ef4539e22bb94456b745a2932a664f40
Source dataset
uspto-grants-1989_03
Patent number
US04814346

Reaction notes

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