General procedure for the synthesis of (1-(4-nitrophenyl)piperidin-3-yl)methanol from 3-hydroxymethylpiperidine and p-fluoronitrobenzene: A mixture of piperidin-3-ylmethanol (2.0 g, 1.0 eq.) with 1-fluoro-4-nitrobenzene (2.94 g, 1.2 eq.) in DMSO (20 mL) was placed in an airtight vial with stirring and the reaction system heated up to 100 °C. The reaction process was monitored by thin layer chromatography (TLC) for 12 hours. Upon completion of the reaction, the reaction mixture was quenched with water and extracted with ethyl acetate (EtOAc). The organic layers were combined, dried over anhydrous sodium sulfate (Na2SO4), filtered and concentrated to afford (1-(4-nitrophenyl)piperidin-3-yl)methanol as a yellow solid (3.0 g, 75% yield). The structure of the product was confirmed by 1H NMR (400 MHz, DMSO-d6): δ 8.08 (d, 1H), 6.805 (d, 1H), 3.98 (m, 1H), 3.81 (d, 1H), 3.64 (m, 1H), 3.53 (m, 1H), 3.041 (m, 1H), 2.878 (m, 1H), 1.838 (m. 3H), 1.621 (m, 2H), 1.294 (d, 1H).
