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

HRID 2068663Notes

Reaction equation

HRID 2068663 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

Reactant 3

HCID 713FormamideHCID 1118Sulfuric AcidHCID 539045465-(2-Bromo-acetyl)-thiophene-3-carboxylic acid methyl ester

Product 1

HCID 581102445-Oxazol-4-yl-thiophene-3-carboxylic acid methyl ester

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-86a16e5b593a4773ba165b03cd688d61
Source dataset
uspto-grants-2012_10
Patent number
US08299063B2

Reaction notes

Loading…