反应详情

Treat a mixture of 2,6-dichloro-4-hydroxy-benzaldehyde (250 g, 1.3 mol) and potassium carbonate (361.8 g, 2.62 mol) in 2 L dimethylformamide with benzyl bromide (268.64 g, 1.57 mol). Stir the reaction at room temperature for 1 hour. Filter off solids and pour into 12 L of water. Filter off solid, wash several times with water, air dry and dissolve in ethyl acetate. Dry over magnesium sulfate, filter and concentrate under vacuum to ˜1.5 L. Allow to sit overnight then filter. Wash solid with minimal amount of hexane and vacuum dry. Concentrate the filtrate under vacuum and triturate with hexane to yield a second crop of product which when combined with the first crop equals 245 g white crystals. Repeat to obtain a 3rd crop of 80 g as a light-tan powder (88% overall yield): 1H NMR (400 MHz, DMSO-d6) δ 10.26 (s, 1H), 7.43 (m, 5H), 7.28 (s, 2H), 5.25 (s, 2H).

1. additionTreat
2. customthe reaction at room temperature for 1 hour
3. filtrationFilter off solids
4. additionpour into 12 L of water
5. filtrationFilter off solid
6. washwash several times with water, air
7. customdry
8. dissolutiondissolve in ethyl acetate
9. dry with materialDry over magnesium sulfate
10. filtrationfilter
11. concentrationconcentrate under vacuum to ˜1.5 L
12. filtrationthen filter
13. washWash solid with minimal amount of hexane and vacuum
14. customdry
15. concentrationConcentrate the filtrate under vacuum
16. customtriturate with hexane
17. customto yield a second crop of product which when
18. customRepeat to obtain a 3rd crop of 80 g
19. customas a light-tan powder (88% overall yield)