Dimethylformamide → 5-Bromo-1-methyl-1H-indole

HRID 488534Notes

Reaction equation

HRID 488534 reaction equation
[Br:1][C:2]1[CH:3]=[C:4]2[C:8](=[CH:9][CH:10]=1)[NH:7][CH:6]=[CH:5]2.[CH2:11]1N2CCN(CC2)C1.CN(C=O)C>C(OCC)(=O)C.O>[Br:1][C:2]1[CH:3]=[C:4]2[C:8](=[CH:9][CH:10]=1)[N:7]([CH3:11])[CH:6]=[CH:5]2

Participants

6

Reactant 3

HCID 6228DimethylformamideHCID 9237DabcoHCID 249055-Bromoindole

Product 1

HCID 2857575-Bromo-1-methyl-1H-indoleYield 989.4%

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 8857Ethyl AcetateSolvent

Conditions

Temperature
92.5 °C

Procedure

To a solution of 5-bromoindole (1.0 g, 5.10 mmol) in DMC (10 mL), DABCO (0.057 g, 0.51 mmol) is added followed by DMF (1 mL). The resulting solution is heated to 90-95° C. for 5 h. The reaction is cooled to RT, and diluted with ethyl acetate (EtOAc, 50 mL) and H2O (50 mL). The organic layer is separated and washed in sequence with H2O (50 mL), 10% aqueous citric acid (2×50 mL) and H2O (4×50 mL). The organic layer is dried over anhydrous sodium sulfate (Na2SO4), filtered and concentrated under vacuum to give 5-bromo-1-methylindole (about 1.06 g, 99%) as a golden colored solid: 1H NMR (CDCl3) δ7.72 (d, 1H), 7.26 (dd, 1H), 7.13 (d, 1H), 7.00 (d, 1H), 6.39 (d, 1H), 3.71 (s, 3H); 13C NMR (CDCl3) δ135.3, 130.1, 129.9, 124.2, 123.2, 112.6, 110.6, 100.5, 32.9; MS m/z 209 [M+1]+.

Workup

  1. temperatureThe reaction is cooled to RT
  2. customThe organic layer is separated
  3. washwashed in sequence with H2O (50 mL), 10% aqueous citric acid (2×50 mL) and H2O (4×50 mL)
  4. dry with materialThe organic layer is dried over anhydrous sodium sulfate (Na2SO4)
  5. filtrationfiltered
  6. concentrationconcentrated under vacuum

Sources & evidence

ORD record
ord-fcd99546cab64b19be0a13349eb9b61d
Source dataset
uspto-grants-2005_12
Patent number
US06972336B2

Reaction notes

Loading…