Acetic Anhydride → Ethyl 5-acetoxyindole-2-carboxylate

HRID 1610927Notes

Reaction equation

HRID 1610927 reaction equation
[OH:1][C:2]1[CH:3]=[C:4]2[C:8](=[CH:9][CH:10]=1)[NH:7][C:6]([C:11]([O:13][CH2:14][CH3:15])=[O:12])=[CH:5]2.[C:16](OC(=O)C)(=[O:18])[CH3:17]>CN(C)C1C=CN=CC=1>[C:16]([O:1][C:2]1[CH:3]=[C:4]2[C:8](=[CH:9][CH:10]=1)[NH:7][C:6]([C:11]([O:13][CH2:14][CH3:15])=[O:12])=[CH:5]2)(=[O:18])[CH3:17]

Participants

4

Procedure

A stirred solution of ethyl 5-hydroxyindole-2-carboxylate (7.79 g) and 4-dimethylaminopyridine (20 mg) in acetic anhydride (80 ml) was heated at 80° C. for 4 hours. The reaction was concentrated in vacuo and the residue was dissolved in ethyl acetate. Combined organic extracts were washed with hydrochloric acid (2 M), saturated aqueous sodium hydrogen carbonate solution, water, aqueous saturated sodium chloride solution and dried. The solution was concentrated in vacuo to yield the product as a yellow solid (9.39 g, 100%). NMR: 1.20 (t, 3H), 2.10 (s, 3H), 4.19 (q, 2), 6.86 (dd, 1H), 6.97 (d, 1H), 7.20 (s, 1H), 7.29 (d, 1H); m/z 248 (M+H+).

Workup

  1. concentrationThe reaction was concentrated in vacuo
  2. dissolutionthe residue was dissolved in ethyl acetate
  3. washCombined organic extracts were washed with hydrochloric acid (2 M), saturated aqueous sodium hydrogen carbonate solution, water, aqueous saturated sodium chloride solution
  4. customdried
  5. concentrationThe solution was concentrated in vacuo

Sources & evidence

ORD record
ord-b2c386d3e5854c898642acb47ddd53dc
Source dataset
uspto-grants-2006_01
Patent number
US06984657B1

Reaction notes

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