Iodine → 5-Iodo-2-methyl-thiazole-4-carboxylic acid ethyl ester

HRID 1984662Notes

Reaction equation

HRID 1984662 reaction equation
[CH3:1][C:2]1[S:3][CH:4]=[C:5]([C:7]([O:9][CH2:10][CH3:11])=[O:8])[N:6]=1.S(=O)(=O)(O)O.II.[I:19](O)(=O)=O.S([O-])([O-])(=O)=S.[Na+].[Na+]>C(O)(=O)C.C(Cl)(Cl)(Cl)Cl>[CH2:10]([O:9][C:7]([C:5]1[N:6]=[C:2]([CH3:1])[S:3][C:4]=1[I:19])=[O:8])[CH3:11]

Participants

8

Conditions

Temperature
80 °C

Procedure

To a solution of ethyl 2-methylthiazole-4-carboxylate (11.2 g, 65.4 mmol) in acetic acid (200 mL) were added sulfuric acid (30%, 20 mL), carbontetrachloride (30 mL), iodine (33.2 g, 131 mmol) and iodic acid (11.5 g, 65.4 mmol) and the resulting reaction mixture was stirred for 19 h at 80° C. After addition of aqueous sodium thiosulfate (1 M, 500 mL) it was extracted with ethyl acetate (1000 mL). The combined organic layers were washed with aqueous sodium carbonate (saturated, 1000 mL), dried over sodium sulfate and concentrated. Purification by chromatography (SiO2, heptane:ethyl acetate=95:5 to 20:80) afforded the title compound (9.00 g, 37%) as a white crystalline solid. MS: m/e=298.1 [M+H]+.

Workup

  1. customthe resulting reaction mixture
  2. extractionwas extracted with ethyl acetate (1000 mL)
  3. washThe combined organic layers were washed with aqueous sodium carbonate (saturated, 1000 mL)
  4. dry with materialdried over sodium sulfate
  5. concentrationconcentrated
  6. customPurification by chromatography (SiO2, heptane:ethyl acetate=95:5 to 20:80)

Sources & evidence

ORD record
ord-2fa0b58ac72f47f0946d6fcad0ebf080
Source dataset
uspto-grants-2009_06
Patent number
US07544704B2

Reaction notes

Loading…