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

HRID 323840Notes

Reaction equation

HRID 323840 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>[CH2:17]([O:16][C:14](=[O:15])[CH2:13][N:1]1[C:9]2[C:4](=[CH:5][CH:6]=[CH:7][CH:8]=2)[CH:3]=[CH:2]1)[CH3:18]

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) δ 7.53 (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-e6c4b964d7ad4f22b3b8eb4ca2f8f132
Source dataset
uspto-grants-2001_04
Patent number
US06214991B1

Reaction notes

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