反应详情

温度

-2 °C

To a mixture of 3,4,5-trimethoxybenzylamine (20.0 g, 0.101 mol), THF (88.0 mL) and triethylamine (14.9 g, 0.147 mol) was added dropwise benzoyl chloride (14.3 g, 0.101 mol) at −6-−3° C., and the dropping funnel was washed with THF (10 mL). The reaction mixture was stirred under a nitrogen atmosphere at −6-2° C. for 1 hr. The consumption of the starting material was confirmed by TLC (hexane/ethyl acetate (1:1)). To the reaction mixture was added water (44 mL) at 2-10° C., and the mixture was extracted three times with ethyl acetate (17, 40, 18 mL). The combined organic layers were washed twice with 18% brine (20 mL), and dried over magnesium sulfate (7.4 g). Silica gel (5.1 g) was added thereto, and the mixture was stirred for 11 min, and filtered through silica gel (19 g). The filtrate was concentrated to 35 g under reduced pressure in a bath at 35° C. To the concentrate was added ethyl acetate, and the solid was dissolved with heating. The solvent was evaporated under reduced pressure (content 52 g) in a bath at 40-30° C. until the content ceased to flow. During evaporation, seed crystals were added thereinto. Ethyl acetate in an amount necessary for filtration was added thereto, and the crystals were collected by filtration, washed with ethyl acetate, and dried under reduced pressure at 50° C. or lower to give N-benzoyl-3,4,5-trimethoxybenzylamine (27.3 g, 89.3%) as white crystals.

1. washthe dropping funnel was washed with THF (10 mL)
2. customThe consumption of the starting material
3. additionTo the reaction mixture was added water (44 mL) at 2-10° C.
4. extractionthe mixture was extracted three times with ethyl acetate (17, 40, 18 mL)
5. washThe combined organic layers were washed twice with 18% brine (20 mL)
6. dry with materialdried over magnesium sulfate (7.4 g)
7. additionSilica gel (5.1 g) was added
8. stirringthe mixture was stirred for 11 min
9. filtrationfiltered through silica gel (19 g)
10. concentrationThe filtrate was concentrated to 35 g under reduced pressure in a bath at 35° C
11. additionTo the concentrate was added ethyl acetate
12. dissolutionthe solid was dissolved
13. temperaturewith heating
14. customThe solvent was evaporated under reduced pressure (content 52 g) in a bath at 40-30° C. until the content
15. customDuring evaporation, seed crystals
16. additionwere added
17. filtrationEthyl acetate in an amount necessary for filtration
18. additionwas added
19. filtrationthe crystals were collected by filtration
20. washwashed with ethyl acetate
21. customdried under reduced pressure at 50° C.