Dimethylformamide → Methyl 4-(5-formylthiophen-2-yl)butanoate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

Freshly distilled POCl3 (0.4 MI, 4.12 mmol) was added to a solution of methyl 4-(thiophen-2-yl)butanoate (1.1 g, 5.97 mmol) in dry DMF (0.7 MI) at 0° C. The reaction mixture was further heated to 110° C. for 1.5 h, then cooled to room temperature and quenched with ice water. The Ph of the reaction mixture was adjusted to ˜7 using aqueous Na2CO3 solution. The organic product was extracted with diethyl ether and the combined extracts were washed with water and brine, dried over anhydrous sodium sulfate and concentrated under reduced pressure to get methyl 4-(5-formylthiophen-2-yl)butanoate (1.0 g, yield 83%), which was carried through without further purification. 1H NMR (300 MHz, CDCl3) δ 9.82 (s, 1H), 7.63-7.61 (d, J=3.7 Hz, 1H), 6.94-6.92 (m, 1H), 3.68 (s, 3H), 2.96-2.91 (t, J=7.5 Hz, 2H), 2.42-2.37 (m, 2H), 2.09-1.99 (m, 2H). MS (ESI) m/z: Calculated for C10H12O3S: 212.05. found: 212.9 (M+H)+

Herkunft & Nachweise