2,2-dimethyl-4-(2-pyridyl)-2H-1-benzopyran → 3,4-dihydro-2,2-dimethyl-4-(2-pyridyl)-2H-1-benzopyran

HRID 892504Notes

Reaction equation

HRID 892504 reaction equation
[CH3:1][C:2]1([CH3:18])[CH:7]=[C:6]([C:8]2[CH:13]=[CH:12][CH:11]=[CH:10][N:9]=2)[C:5]2[CH:14]=[CH:15][CH:16]=[CH:17][C:4]=2[O:3]1.[H][H]>C(O)C.[Pd]>[CH3:1][C:2]1([CH3:18])[CH2:7][CH:6]([C:8]2[CH:13]=[CH:12][CH:11]=[CH:10][N:9]=2)[C:5]2[CH:14]=[CH:15][CH:16]=[CH:17][C:4]=2[O:3]1

Participants

5

Reactant 2

HCID 187551522,2-dimethyl-4-(2-pyridyl)-2H-1-benzopyranHCID 178418361HCID 178418361, compound

Product 1

HCID 198956113,4-dihydro-2,2-dimethyl-4-(2-pyridyl)-2H-1-benzopyranYield 72.3%

Reagents, catalysts & solvents 2

HCID 23938PalladiumCatalystHCID 702EthanolSolvent

Procedure

6.95 g of 2,2-dimethyl-4-(2-pyridyl)-2H-1-benzopyran were dissolved in 100 ml of ethanol and shaken at room temperature with 10% palladium-on-charcoal under a hydrogen atmosphere. After the required volume of hydrogen had been taken up the catalyst was filtered off, the filtrate was evaporated and the residue was recrystallized from n-hexane to give 5.07 g of 3,4-dihydro-2,2-dimethyl-4-(2-pyridyl)-2H-1-benzopyran of melting point 99°-101° C.

Workup

  1. filtrationwas filtered off
  2. customthe filtrate was evaporated
  3. customthe residue was recrystallized from n-hexane

Sources & evidence

ORD record
ord-b50302337b7d45c28953d17a540f89b9
Source dataset
uspto-grants-1992_06
Patent number
US05118694

Reaction notes

Loading…