Step 1: Borane methyl sulfide complex (6.4 mL, 12.8 mmol) was slowly added to a solution of 3-(2-thienyl)propionic acid (1.0 g, 6.4 mmol) in tetrahydrofuran (THF, 18 mL), keeping the reaction temperature at 0 °C. The reaction mixture was stirred continuously at 0 °C for 2 h, and then brought to room temperature and continued stirring for 3 h. The reaction mixture was then cooled to room temperature. Upon completion of the reaction, the mixture was cooled to 0 °C and saturated potassium carbonate solution (5 mL) was slowly added to quench the reaction. The aqueous layer was separated and the organic phase was extracted with ethyl acetate (2 x 15 mL) and ether (2 x 15 mL), respectively. All organic phases were combined, dried with anhydrous sodium sulfate, filtered and concentrated to dryness under reduced pressure to afford the target product 3-(2-thienyl)-1-propanol as a colorless oil (1.0 g, 100% yield). The product was characterized by 1H NMR (CDCl3, 400 MHz): δ 7.18-7.17 (m, 1H), 6.99-6.96 (m, 1H), 6.87-6.86 (m, 1H), 3.79-3.74 (m, 2H), 3.0 (t, J = 7.6 Hz, 2H), 2.4-1.97 (m, 2H).
