反应详情

TiCl4 (1M in DCM, 7.2 ml, 7.2 mmol) was added to a solution of tetraisopropyl orthotitanate (0.71 ml 2.4 mmol) in DCM (40 ml) held at 0° C. under inert atmosphere. The mixture was stirred for 15 minutes, then (4S)-3-{[(4-methoxybenzyl)thio]acetyl}-4-phenyl-1,3-oxazolidin-2-one (3.4 g, 9.6 mmol) in dry DCM (20 ml) was added and the mixture was stirred for five minutes. Then tert-butyl (4-{[(4-fluorophenyl)imino]methyl}phenoxy)acetate (6.3 g, 19.0 mmol) in dry DCM (30 ml) was added and the mixture was given −40° C. and stirred for 20 minutes. Ethyl diisopropyl amine (3.3 ml, 19.0 mmol) was added and the mixture was stirred at −40° C. for 19 hours. The mixture was then given −78° C., added isopropanol (50 ml) and slowly given room temperature over night. Water (100 ml) was added and the mixture was stirred for 35 minutes at room temperature and then extracted twice with diethyl ether. The combined organic layer was washed with water, dried (MgSO4) and concentrated under reduced pressure. The crude product was dissolved in methanol and an off-white precipitate formed. Filtration and drying afforded 1.7 g (26%) of the title compound as an off-white solid. NMR (200 MHz): 1.5 (s, 9H), 3.65 (s, 1H), 3.8 (s, 3H), 4.1 (m, 1H), 4.4-4.6 (m, 4H), 5.0-5.2 (m, 2H), 5.4 (m, 1H), 6.4-6.6 (m, 2H), 6.7-7-4 (m, 15H).

1. customheld at 0° C. under inert atmosphere
2. stirringthe mixture was stirred for five minutes
3. customwas given −40° C.
4. stirringstirred for 20 minutes
5. stirringthe mixture was stirred at −40° C. for 19 hours
6. customwas then given −78° C.
7. stirringthe mixture was stirred for 35 minutes at room temperature
8. extractionextracted twice with diethyl ether
9. washThe combined organic layer was washed with water
10. dry with materialdried (MgSO4)
11. concentrationconcentrated under reduced pressure
12. dissolutionThe crude product was dissolved in methanol
13. customan off-white precipitate formed
14. filtrationFiltration
15. customdrying