Water → (Z)-3-(4-bromo-3-methoxy-phenylamino)-but-2-enoic acid ethyl ester

HRID 2415483Notes

Reaction equation

HRID 2415483 reaction equation
[Br:1][C:2]1[CH:7]=[CH:6][C:5]([NH2:8])=[CH:4][C:3]=1[O:9][CH3:10].[C:11]([O:17][CH2:18][CH3:19])(=[O:16])[CH2:12][C:13]([CH3:15])=O.O>C1CCCCC1.O.C1(C)C=CC(S(O)(=O)=O)=CC=1>[CH2:18]([O:17][C:11](=[O:16])/[CH:12]=[C:13](\[NH:8][C:5]1[CH:6]=[CH:7][C:2]([Br:1])=[C:3]([O:9][CH3:10])[CH:4]=1)/[CH3:15])[CH3:19]

Participants

6

Reactant 3

HCID 962WaterHCID 8868Ethyl AcetoacetateHCID 70182544-Bromo-3-methoxyaniline

Product 1

HCID 69287166(Z)-3-(4-bromo-3-methoxy-phenylamino)-but-2-enoic acid ethyl esterYield 68.9%

Reagents, catalysts & solvents 2

HCID 521998p-Toluenesulfonic acid monohydrateCatalystHCID 8078CyclohexaneSolvent

Procedure

7.66 g (37.9 mmol) of 4-bromo-3-methoxy-phenylamine (preparation described in Tetrahedron Lett., 1995, 7583) were dissolved in 80 ml of cyclohexane at 70° C. and subsequently treated under stirring with 72 mg (0.38 mmol) of p-toluenesulfonic acid monohydrate and 4.93 g (37.9 mmol) of ethyl acetoacetate. The solution was then heated at reflux for 3.5 h with a water separator funnel connected. It was then cooled to RT and concentrated in vacuo. The residue was applied to a silica gel column with hexane/diethyl ether (3:1) as eluent. Combinations of the purified fractions and concentration in vacuo gave 8.2 g (68.8%) of the (Z)-3-(4-bromo-3-methoxy-phenylamino)-but-2-enoic acid ethyl ester, as a yellow solid. ISP mass spectrum, m/e: 316.2(M+1 calculated for C13H16BrNO3: 316).

Workup

  1. additionsubsequently treated
  2. temperatureThe solution was then heated
  3. concentrationconcentrated in vacuo
  4. concentrationCombinations of the purified fractions and concentration in vacuo

Sources & evidence

ORD record
ord-e6c9897c8f6d498fb4fa75927f0a7fee
Source dataset
uspto-grants-2004_11
Patent number
US06818767B2

Reaction notes

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