Indole → Indol-1-yl-acetic acid ethyl ester

HRID 2230787Notes

Reaction equation

HRID 2230787 reaction equation
[NH:1]1[C:9]2[C:4](=[CH:5][CH:6]=[CH:7][CH:8]=2)[CH:3]=[CH:2]1.[H-].[Na+].Br[CH2:13][C:14]([O:16][CH2:17][CH3:18])=[O:15]>C(#N)C>[N:1]1([CH2:13][C:14]([O:16][CH2:17][CH3:18])=[O:15])[C:9]2[C:4](=[CH:5][CH:6]=[CH:7][CH:8]=2)[CH:3]=[CH:2]1

Participants

5

Reactant 3

HCID 798IndoleHCID 7748Ethyl bromoacetateHCID 24758Sodium hydride

Product 1

HCID 967684Indol-1-yl-acetic acid ethyl ester

Reagents, catalysts & solvents 1

HCID 6342AcetonitrileSolvent

Procedure

Under an atmosphere of nitrogen, a solution of indole (15.0 g, 128 mmol) in dry acetonitrile (300 mL, 0.4 M) was treated with sodium hydride (95%, 3.69 g, 153 mmol) and stirred for 30 min. Ethyl bromoacetate (17.0 mL, 153 mmol) was added in a dropwise manner over 10 min and the solution was stirred at room temperature for 16 h. After concentrating under reduced pressure, the resulting residue was dissolved in ethyl acetate and washed with sat'd. aq. NaCl. The organic extracts were dried over MgSO4, filtered and concentrated. The crude product was purified by flash column chromatography (50% ethyl acetate in heptane): Rf0.25 (40% ethyl acetate in heptane) 1H NMR (DMSO-d6, 300 MHz) δ7.53 (d, J=6.3 Hz, 1 H), 7.38-7.31 (m, 2 H), 7.11 (br t, J=7.2 Hz, 1 H), 7.02 (br t, J=7.2 Hz, 1 H), 6.45-6.43 (m, 1 H), 5.10 (s, 2 H), 4.12 (q, J=7.2 Hz, 2 H), 1.19 (t, J=7.2 Hz, 3 H)

Workup

  1. stirringthe solution was stirred at room temperature for 16 h
  2. concentrationAfter concentrating under reduced pressure
  3. dissolutionthe resulting residue was dissolved in ethyl acetate
  4. washwashed with sat'd
  5. dry with materialThe organic extracts were dried over MgSO4
  6. filtrationfiltered
  7. concentrationconcentrated
  8. customThe crude product was purified by flash column chromatography (50% ethyl acetate in heptane)

Sources & evidence

ORD record
ord-1d48446fcb0a40e0a48aeb07bc2ae578
Source dataset
uspto-grants-2002_07
Patent number
US06426344B2

Reaction notes

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