Ethyl 7-bromo-1H-indole-2-carboxylate → (r)-7-Bromo-1-(2-tert-butoxycarbonylamino-1-methyl-ethyl)-1h-indole-2-carboxylic acid ethyl ester

HRID 1760599Notes

Reaction equation

HRID 1760599 reaction equation
[CH2:1]([O:3][C:4]([C:6]1[NH:7][C:8]2[C:13]([CH:14]=1)=[CH:12][CH:11]=[CH:10][C:9]=2[Br:15])=[O:5])[CH3:2].CC(C)([O-])C.[K+].[C:22]([O:26][C:27]([N:29]1[CH2:33][C@H:32]([CH3:34])OS1(=O)=O)=[O:28])([CH3:25])([CH3:24])[CH3:23]>CN(C)C=O>[CH2:1]([O:3][C:4]([C:6]1[N:7]([C@H:32]([CH3:34])[CH2:33][NH:29][C:27]([O:26][C:22]([CH3:25])([CH3:24])[CH3:23])=[O:28])[C:8]2[C:13]([CH:14]=1)=[CH:12][CH:11]=[CH:10][C:9]=2[Br:15])=[O:5])[CH3:2]

Participants

5

Reactant 3

HCID 7017885Ethyl 7-bromo-1H-indole-2-carboxylateHCID 11195739(s)-Tert-butyl 5-methyl-1,2,3-oxathiazolidine-3-carboxylate 2,2-dioxideHCID 23665647Potassium tert-butoxide

Product 1

HCID 68887802(r)-7-Bromo-1-(2-tert-butoxycarbonylamino-1-methyl-ethyl)-1h-indole-2-carboxylic acid ethyl ester

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

A solution of 8.1 g (30.1 mmol) 7-bromo-1H-indole-2-carboxylic acid ethyl ester in 120 ml N,N-dimethylformamide was cooled to 0° C. and 3.55 g (31.6 mmol) potassium tert-butoxide was added. After 30 min., 7.86 g (33.1 mmol) (S)-5-methyl-2,2-dioxo-[1,2,3]oxathiazolidine-3-carboxylic acid tert-butyl ester were added and the cooling bath was removed. After 20 h the reaction mixture was poured on 10% aqueous citric acid solution and ethyl acetate. The organic layer was dried over magnesium sulfate, filtered and evaporated. The resulting yellow oil was chromatographed on silica gel (0.032-0.063 mm) with tert-butyl methyl ether: n-hexane (1:8) as eluant to give the desired compound as a yellow oil. ISP-MS: m/e=427.3 ([M+H+]).

Workup

  1. customthe cooling bath was removed
  2. additionAfter 20 h the reaction mixture was poured on 10% aqueous citric acid solution and ethyl acetate
  3. dry with materialThe organic layer was dried over magnesium sulfate
  4. filtrationfiltered
  5. customevaporated
  6. customThe resulting yellow oil was chromatographed on silica gel (0.032-0.063 mm) with tert-butyl methyl ether: n-hexane (1:8) as eluant

Sources & evidence

ORD record
ord-1486662615d64122a6df75de1cc7a961
Source dataset
uspto-grants-2005_01
Patent number
US06844345B2

Reaction notes

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