Formamide → 5-Oxazol-4-yl-thiophene-3-carboxylic acid methyl ester

HRID 1914593

Reaction equation

HRID 1914593 reaction equation
[CH3:1][O:2][C:3]([C:5]1[CH:9]=[C:8]([C:10](=O)[CH2:11]Br)[S:7][CH:6]=1)=[O:4].S(=O)(=O)(O)O.[CH:19]([NH2:21])=[O:20]>>[CH3:1][O:2][C:3]([C:5]1[CH:9]=[C:8]([C:10]2[N:21]=[CH:19][O:20][CH:11]=2)[S:7][CH:6]=1)=[O:4]

Participants

4

Conditions

Temperature
150 °C

Procedure

5-(2-Bromo-acetyl)-thiophene-3-carboxylic acid methyl ester (0.60 g, 2.28 mmol) was suspended in formamide (10 mL) then sulfuric acid (1 mL) was added and the tube purged with nitrogen then sealed. The mixture was heated at 150° C. by microwave irradiation for 15 minutes. The resultant solution was diluted with HCl (1 N) and water and extracted with ethyl acetate (×3). The organic phase was dried over sodium sulfate and evaporated then purified by chromatography on a silica II cartridge, eluting with 1:1 DCM:cyclohexane to afford 5-oxazol-4-yl-thiophene-3-carboxylic acid methyl ester as a pale yellow solid (0.197 g). LCMS m/z 210.14 [M+H]+ R. T.=3.64 min (Analytical Method 9).

Workup

  1. customthe tube purged with nitrogen
  2. customthen sealed
  3. additionThe resultant solution was diluted with HCl (1 N) and water
  4. extractionextracted with ethyl acetate (×3)
  5. dry with materialThe organic phase was dried over sodium sulfate
  6. customevaporated
  7. customthen purified by chromatography on a silica II cartridge
  8. washeluting with 1:1 DCM

Sources & evidence

ORD record
ord-81f9109593554d81b4f5f8e543e1fb83
Source dataset
uspto-grants-2013_12
Patent number
US08614209B2

Linked notes

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