[Synthesis]
Example 8. Synthesis of 2-(pyridin-2-yl)propan-2-ol (PyPrOH) and 1-phenyl-1-(pyridin-2-yl)ethanol (PPE). 2-Benzoylpyridine (8.3 mmol) was dissolved in dry ether (100 mL) in a 250 mL Schlenk flask that was pre-oven dried. The reaction system was cooled to -78°C, followed by the slow addition of methyl lithium (12.9 mL, 1.6 M ether solution) over 15 min. The resulting yellow solution was stirred at -78°C for 1 hour and then slowly warmed to room temperature. Upon completion of the reaction, the reaction was quenched by the addition of saturated aqueous ammonium chloride solution (30 mL) and the mixture was extracted with ethyl acetate (3 x 75 mL). The organic phases were combined, dried over anhydrous sodium sulfate and concentrated under reduced pressure to remove the solvent. The crude product was purified by fast column chromatography (silica gel, eluent ratio: 1:1 ethyl acetate/dichloromethane for PyPrOH, 1:3 ethyl acetate/dichloromethane for PPE) to give a light yellow, oily target product. 55% yield of PyPrOH was obtained.PyPrOH NMR Hydrogen spectrum (CDCl3, 300 MHz): δ 8.52 (d, J = 4.8 Hz , 1H), 7.71 (t, J = 7.8 Hz, 1H), 7.38 (d, J = 8.1 Hz, 1H), 7.21 (t, J = 6.2 Hz, 1H), 5.08 (s, 1H), 1.54 (s, 6H). 97% yield of PPE. NMR hydrogen spectrum of PPE (CDCl3, 300 MHz): δ 8.52 (m, 1H), 7.65 (td, J = 4.8 Hz), 1.54 (s, 6H). 7.65 (td, J = 7.8, 1.8 Hz, 1H), 7.48 (m, 2H), 7.31 (m, 3H), 7.17-7.26 (m, 2H), 5.85 (s, 1H), 1.94 (s, 3H). |