m-Chloroperbenzoic acid → Ethyl 3-methylisothiazole-4-carboxylate

HRID 1782153Notes

Reaction equation

HRID 1782153 reaction equation
[CH2:1]([O:3][C:4](=[O:11])[C:5]([CH:9]=[S:10])=[C:6]([NH2:8])[CH3:7])[CH3:2].ClC1C=CC=C(C(OO)=O)C=1>C(O)C.CCOCC>[CH2:1]([O:3][C:4]([C:5]1[C:6]([CH3:7])=[N:8][S:10][CH:9]=1)=[O:11])[CH3:2]

Participants

5

Reactant 2

HCID 70297m-Chloroperbenzoic acidHCID 766117413-Amino-2-thioformyl-but-2-enoic acid ethyl ester

Product 1

HCID 12371906Ethyl 3-methylisothiazole-4-carboxylate

Reagents, catalysts & solvents 2

HCID 702EthanolSolvent2×HCID 3283Diethyl EtherSolvent

Procedure

To a solution of 3-amino-2-thioformyl-but-2-enoic acid ethyl ester (method 52) (25.6 g, 147 mmol) in ethanol (300 mL), was added m-chloroperbenzoic acid (33.3 g, 77%, 149 mmol) in ethanol (200 mL) dropwise with stirring at room temperature. After the completion of the addition the reaction mixture was heated at 75° C. for 2 h after which the MS showed the complete disappearance of the starting material. The reaction mixture was diluted with ether (500 mL) and the ethereal solution was washed with 0.1 M NaOH solution (3×500 mL) and once with water (400 mL) dried (Na2SO4) and concentrated to get the pure product as light brown oil. Yield 23.5 g (93%). 1NMR (300 MHz) δ: 1.40 (t, 3H), 2.73 (s, 3H), 5.07 (t, 1H), 4.36 (q, 2H), 9.24 (s, 1H).

Workup

  1. additionAfter the completion of the addition the reaction mixture
  2. temperaturewas heated at 75° C. for 2 h after which the MS
  3. washthe ethereal solution was washed with 0.1 M NaOH solution (3×500 mL) and once with water (400 mL)
  4. dry with materialdried (Na2SO4)
  5. concentrationconcentrated

Sources & evidence

ORD record
ord-727584dd7ec24f73a180017f95f08213
Source dataset
uspto-grants-2009_03
Patent number
US07498333B2

Reaction notes

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