110238-91-0

6638-79-5

156353-01-4

1. Methyl tetrahydropyran-4-carboxylate (1.33 mL, 10.0 mmol) was dissolved in anhydrous THF (20 mL), N,O-dimethylhydroxylamine hydrochloride (1.51 g, 15.5 mmol) was added, and mixed with stirring. 2. Under argon protection, the reaction system was cooled to -30 °C, THF solution of isopropylmagnesium chloride (2.0 mol/L, 15.0 mL, 30.0 mmol) was slowly added dropwise, and the reaction was stirred for 1 hour keeping the temperature at -5 °C. The reaction was then stirred for 1 hour. 3. After completion of the reaction, the reaction was quenched by adding water to the mixture and the organic phase was extracted with ethyl acetate. 4. The organic layer was washed with saturated brine, dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure to remove the solvent. 5. The crude product was purified by distillation under reduced pressure to afford N-methoxy-N-methyltetrahydropyran-4-carboxamide (1.00 g, 58% yield). 6. The product was characterized as follows: boiling point 125-129 °C/8.0 hPa; 1H NMR (CDCl3, δ ppm): 1.57-1.66 (m, 2H), 1.77-1.93 (m, 2H), 2.85-2.94 (m, 1H), 3.18 (s, 3H), 3.44 (ddd, J = 2.4, 11.9, 11.9 Hz, 2H), 3.69 (s, 2H), 3.44 (ddd, J = 2.4, 11.9, 11.9 Hz, 2H). 2H), 3.69 (s, 3H), 4.00 (ddd, J = 2.4, 11.9, 11.9 Hz, 2H).