POCl3 (0.88 mL, 9.53 mmol) was added at −25° C. drop wise over 5 min under nitrogen, to a stirred solution of 6-isopropylpyridine-2-carboxylic acid (106, 1.43 g, 8.66 mmol) and 6-acetyl-3-methoxy-2-methylaniline (1.55 g, 8.66 mmol) in dry pyridine (70 mL). The resulting solution was stirred at −10° C. for 2.5 h. Then, the reaction mixture was poured on ice, neutralized with aqueous sodium bicarbonate and extracted 3 times with AcOEt. The organic layers were combined, washed with brine, dried (Na2SO4) and evaporated. The residue was purified by column chromatography (hexanes/AcOEt, 3:1) to give 3.54 g (72%) of the title compound 107: m/z=327 (M+H)+.
