Methanol → 4-(2-Thienyl)butanoic acid methyl ester

HRID 874987

Reaction equation

HRID 874987 reaction equation
OS(O)(=O)=O.[S:6]1[CH:10]=[CH:9][CH:8]=[C:7]1[CH2:11][CH2:12][CH2:13][C:14]([OH:16])=[O:15].[CH3:17]O>>[S:6]1[CH:10]=[CH:9][CH:8]=[C:7]1[CH2:11][CH2:12][CH2:13][C:14]([O:16][CH3:17])=[O:15]

Participants

4

Reactant 3

HCID 887MethanolHCID 1118Sulfuric AcidHCID 783864-(2-Thienyl)Butyric Acid

Product 1

HCID 1407664-(2-Thienyl)butanoic acid methyl esterYield 89%

Conditions

Temperature
70 °C

Procedure

A catalytic amount of conc. H2SO4 (1 MI) was added to a solution of 4-(thiophen-2-yl)butanoic acid (1.2 g, 7.05 mmol) in dry MeOH (30 MI) at 0° C. The resulting reaction mixture was heated to 70° C. for 4 h, cooled to room temperature, and concentrated under reduced pressure. The mixture was then diluted with water and extracted with EtOAc. The combined extracts were washed with water and brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The crude product was purified by column chromatography (silica 60-120 mesh, eluant 5-10% EtOAc in petroleum ether) to get methyl 4-(thiophen-2-yl)butanoate (1.1 g, yield 89%). 1H NMR (300 MHz, CDCl3) δ 7.14-7.12 (m, 1H), 6.94-6.91 (m, 1H), 6.81-6.80 (m, 1H), 3.68 (s, 3H), 2.91-2.86 (t, J=7.5 Hz, 2H), 2.41-2.36 (m, 2H), 2.07-1.97 (m, 2H).

Workup

  1. customThe resulting reaction mixture
  2. temperaturecooled to room temperature
  3. concentrationconcentrated under reduced pressure
  4. additionThe mixture was then diluted with water
  5. extractionextracted with EtOAc
  6. washThe combined extracts were washed with water and brine
  7. dry with materialdried over anhydrous sodium sulfate
  8. concentrationconcentrated under reduced pressure
  9. customThe crude product was purified by column chromatography (silica 60-120 mesh, eluant 5-10% EtOAc in petroleum ether)

Sources & evidence

ORD record
ord-9da23b75684849b89d77e5ea8ddd1d1a
Source dataset
uspto-grants-2015_03
Patent number
US08981084B2

Linked notes

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