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

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

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).

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