Synthesis
General procedure for the synthesis of (2-bromo-3-thiophene) methanol from 3-thiophene methanol: 3-hydroxymethylthiophene (12, 4.06 g, 35.6 mmol) was dissolved in 18 mL of acetic acid at room temperature, followed by the addition of N-bromosuccinimide (6.34 g, 35.6 mmol), and the reaction was stirred for 45 min. After completion of the reaction, the reaction was quenched with 1 mL of water and the mixture was poured into 250 mL of ether and washed sequentially with 100 mL of water and 100 mL of 10% aqueous NaHCO3. The organic layer was separated, dried with anhydrous Na2SO4 and the solvent was concentrated. Finally, 6.25 g of crude product 13 was obtained in 91% yield, which was directly used in the next reaction without further purification.
References
[1] Organic Letters, 2008, vol. 10, # 17, p. 3665 - 3668
[2] Patent: WO2004/65384, 2004, A1. Location in patent: Page 36; 16/19
[3] Chemistry Letters, 2013, vol. 42, # 10, p. 1170 - 1172
[4] Patent: WO2008/17164, 2008, A1. Location in patent: Page/Page column 34
[5] Journal of Medicinal Chemistry, 2010, vol. 53, # 5, p. 2227 - 2238
