Sodium Hydroxide → 4-(3,4-Dimethoxyphenyl)-1H-indole

HRID 982997Notes

Reaction equation

HRID 982997 reaction equation
CC1(C)C(C)(C)OB([C:9]2[CH:17]=[CH:16][CH:15]=[C:14]3[C:10]=2[CH:11]=[CH:12][NH:13]3)O1.Br[C:20]1[CH:21]=[C:22]([O:28][CH3:29])[C:23]([O:26][CH3:27])=[CH:24][CH:25]=1.[OH-].[Na+]>C1COCC1.[Pd].C(OCC)(=O)C>[CH3:27][O:26][C:23]1[CH:24]=[C:25]([C:9]2[CH:17]=[CH:16][CH:15]=[C:14]3[C:10]=2[CH:11]=[CH:12][NH:13]3)[CH:20]=[CH:21][C:22]=1[O:28][CH3:29]

Participants

7

Reactant 3

HCID 14798Sodium HydroxideHCID 76114Benzene, 4-bromo-1,2-dimethoxy-HCID 113224711H-Indole-4-boronic acid, pinacol ester

Product 1

HCID 225616844-(3,4-Dimethoxyphenyl)-1H-indoleYield 72%

Reagents, catalysts & solvents 3

HCID 23938PalladiumCatalystHCID 8028TetrahydrofuranSolventHCID 8857Ethyl AcetateSolvent

Conditions

Temperature
80 °C

Procedure

To a mixture of 4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-1H-indole (10 g, 41.1 mmol), and 4-bromoveratrole (8.93 g, 41.1 mmol) in THF (140 mL) were added Palladium catalyst Pd(PPh3)4 (1.43 g, 1.23 mmol) and the freshly prepared sodium hydroxide solution (5.08 g in 58 mL of water). The system was degassed and then charged with nitrogen. The degas procedure was repeated for three times. The mixture was stirred under nitrogen at 80° C. oil bath for overnight. TLC showed the completion of the coupling reaction. The mixture was cooled to room temperature, diluted with ethyl acetate, and separated from water layer. The ethyl acetate solution was washed with brine, and dried over Na2SO4. After filtration, the solvents were evaporated, and the crude product was purified by a silica gel column to give 7.47 g (72%) of 4-(3,4-dimethoxy-phenyl)1H-indole.

Workup

  1. customThe system was degassed
  2. additioncharged with nitrogen
  3. customthe completion of the coupling reaction
  4. temperatureThe mixture was cooled to room temperature
  5. customseparated from water layer
  6. washThe ethyl acetate solution was washed with brine
  7. dry with materialdried over Na2SO4
  8. filtrationAfter filtration
  9. customthe solvents were evaporated
  10. customthe crude product was purified by a silica gel column

Sources & evidence

ORD record
ord-1ed216a4ada04410b3f664af3a72b230
Source dataset
uspto-grants-2005_03
Patent number
US06861418B2

Reaction notes

Loading…