Acetic Anhydride → Ethyl 5-acetoxyindole-2-carboxylate

HRID 1582632Notes

Reaction equation

HRID 1582632 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

Reactant 2

HCID 7918Acetic AnhydrideHCID 90677Ethyl 5-hydroxy-1H-indole-2-carboxylate

Product 1

HCID 11379620Ethyl 5-acetoxyindole-2-carboxylateYield 100%

Reagents, catalysts & solvents 1

HCID 142844-(Dimethylamino)pyridineCatalyst

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: δ 1.20 (t, 3H), 2.10 (s, 3H), 4.19 (q, 2H), 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-0270d477703d45aaadb9a8c1cd2f9e89
Source dataset
uspto-grants-2004_05
Patent number
US06737435B1

Reaction notes

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