Ethyl Indole-3-carboxylate → 1-tert-Butyl 3-ethyl 1H-indole-1,3-dicarboxylate

HRID 863299Notes

Reaction equation

HRID 863299 reaction equation
[NH:1]1[C:9]2[C:4](=[CH:5][CH:6]=[CH:7][CH:8]=2)[C:3]([C:10]([O:12][CH2:13][CH3:14])=[O:11])=[CH:2]1.[C:15]([O:19][C:20](=O)[O:21]C(C)(C)C)([CH3:18])([CH3:17])[CH3:16]>CN(C1C=CN=CC=1)C.C(#N)C.C(OCC)(=O)C>[C:15]([O:19][C:20]([N:1]1[C:9]2[C:4](=[CH:5][CH:6]=[CH:7][CH:8]=2)[C:3]([C:10]([O:12][CH2:13][CH3:14])=[O:11])=[CH:2]1)=[O:21])([CH3:18])([CH3:17])[CH3:16]

Participants

6

Reactant 2

HCID 247965Ethyl Indole-3-carboxylateHCID 10219638Carbonic acid, bis(1,1-dimethylethyl) ester

Product 1

HCID 539833451-tert-Butyl 3-ethyl 1H-indole-1,3-dicarboxylateYield 105.9%

Reagents, catalysts & solvents 3

HCID 142844-(Dimethylamino)pyridineCatalystHCID 6342AcetonitrileSolventHCID 8857Ethyl AcetateSolvent

Procedure

A solution of 3.15 g of ethyl indole-3-carboxylate, 4.36 g of di-tert-butylcarbonate and 0.02 g of 4-DMAP in 30 ml of acetonitrile is stirred at room temperature for 15 min. The reaction mixture is then diluted with 200 ml of ethyl acetate. The organic phase is washed with dilute hydrochloric acid, water and saturated sodium chloride solution in succession, dried over sodium sulfate and concentrated. Purification by means of FC over 80 g of silica gel with a 15:1 mixture of hexane and ethyl acetate as the mobile phase gives 5.1 g of the title compound: Rf (G)=0.41.

Workup

  1. washThe organic phase is washed with dilute hydrochloric acid, water and saturated sodium chloride solution in succession
  2. dry with materialdried over sodium sulfate
  3. concentrationconcentrated
  4. customPurification by means of FC over 80 g of silica gel
  5. additionwith a 15:1 mixture of hexane and ethyl acetate as the mobile phase

Sources & evidence

ORD record
ord-cefa6350b4114ac1b007557d7d94c5d9
Source dataset
uspto-grants-1998_02
Patent number
US05719141

Reaction notes

Loading…