反应详情

Add sodium tetrahydroborate (1.8 g, 47.4 mmol) in portions to a solution of 1-benzyl-4-isopropyl-pyridin-1-ium bromide (11.1 g, 36.5 mmol) in EtOH (55 mL) at 0° C. Allow the reaction mixture to reach ambient temperature slowly and stir overnight. Add 10 mL of water and remove the organic solvent under vacuum. Add water and then adjust the pH with HCl (5M) to a pH of 1-2. Stir the mixture for 15 min and then add NaOH (2M) until the pH is 8-9. Extract the aqueous layer with EtOAc, combine the organic layers; and sequentially wash with NaOH (2M) then brine. Dry the organic over anhydrous sodium sulphate; filter; and concentrate the filtrate. Purify the compound by chromatography on a silica gel cartridge eluting with hexane:ethyl acetate (9:1, 7:3, 5:5, and then 100% ethyl acetate) to obtain the title compound as a pale yellow oil (6.7 g, 83%). MS (m/z): 216 (M+1).

1. customto reach ambient temperature
2. customremove the organic solvent under vacuum
3. stirringStir the mixture for 15 min
4. extractionExtract the aqueous layer with EtOAc
5. washand sequentially wash with NaOH (2M)
6. dry with materialDry the organic over anhydrous sodium sulphate
7. filtrationfilter
8. concentrationand concentrate the filtrate
9. customPurify the compound by chromatography on a silica gel cartridge
10. washeluting with hexane:ethyl acetate (9:1, 7:3, 5:5