反应详情

m-Nitrobenzaldehyde (0.456 g, 3.02 mmol) and titanium isopropoxide (1.23 mL, 4.12 mmol) were added to a solution of Example 125k (1.2 g, 2.75 mmol) in methanol (75 mL) and refluxed for 1.5 h. Sodium cyanoborohydride (0.188 g, 2.75 mmol) was then added to the reaction mixture at 30° C. and refluxed for 3 h. It was cooled, treated with water and filtered. The filtrate was extracted with chloroform. The organic layer was washed with water, brine, dried, concentrated and purified using flash chromatography (silica gel, 5% methanol/chloroform) to obtain the title compound. Yield: 0.74 g (48%); 1H NMR (CDCl3): δ 2.6 (t, 4H, 2CH2), 2.63 (s, 3H, CH3), 3.22 (t, 4H, 2CH2), 3.63 (s, 2H, CH2), 3.9 (s, 3H, OCH3), 5.2 (s, 2H, CH2), 6.73 (s, 1H, Ar), 6.9 (s, 1H, Ar), 7.5 (t, 1H, Ar), 7.7 (d, 1H, Ar), 8.1 (s, 1H, Ar), 8.15 (d, 1H, Ar), 8.25 (s, 1H, Ar), 8.45 (s, 1H, Ar); MS: m/e (ES+) 573 (M+1).

1. temperaturerefluxed for 1.5 h
2. temperaturerefluxed for 3 h
3. temperatureIt was cooled
4. filtrationfiltered
5. extractionThe filtrate was extracted with chloroform
6. washThe organic layer was washed with water, brine
7. customdried
8. concentrationconcentrated
9. custompurified