反应详情

To a solution of 1-(4-ethoxycarbonyl-1,3-thiazol-2-yl)-4-hydroxypiperidine (1.00 g, 3.90 mmol) (obtained as described in Reference Example 13(2)) in dimethylformamide (50 ml) were added t-butyldimethylsilyl chloride (1.2 g, 7.96 mmol) and imidazole (0.6 g, 8.8 mmol) in an ice bath. The reaction mixture was brought to room temperature in 10 minutes and then stirred for 18 hours. After checking the completion of the reaction, ethanol was added thereto in an ice bath, and the reaction mixture was then stirred at room temperature for 30 minutes. The reaction mixture was partitioned between ethyl acetate and saturated aqueous sodium hydrogencarbonate solution. The organic layer was washed with saturated aqueous sodium chloride solution, dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The obtained residue was purified by chromatography on a silica gel column using n-hexane:ethyl acetate (4:1) as the eluant to afford 4-t-butyidimethylsilyloxy-1-(4-ethoxycarbonyl-1,3-thiazol-2-yl)azetidine (1.38 g, yield 95%) as a pale yellow oil.

1. additionwas added
2. stirringin an ice bath, and the reaction mixture was then stirred at room temperature for 30 minutes
3. customThe reaction mixture was partitioned between ethyl acetate and saturated aqueous sodium hydrogencarbonate solution
4. washThe organic layer was washed with saturated aqueous sodium chloride solution
5. dry with materialdried over anhydrous magnesium sulfate
6. filtrationfiltered
7. concentrationconcentrated under reduced pressure
8. customThe obtained residue was purified by chromatography on a silica gel column