反应详情

To a 1% acetic acid-dimethylformamide (10 mL) solution of tert-butyl 2,8-diazaspiro[4.5]decane-2-carboxylate (1.28 g) and 3-methylthiophene-2-carbaldehyde (700 mg), sodium triacetoxyborohydride (1.96 g) was added. The reaction solution was stirred at room temperature for 15 hours. To the reaction solution, an aqueous 5N sodium hydroxide solution (10 mL) was added. The aqueous layer was washed twice with dichloromethane (100 mL) The combined organic layer was washed with saturated sodium chloride solution (50 mL) and then dried over anhydrous magnesium sulfate. After removing the anhydrous magnesium sulfate by filtration, the filtrate was concentrated. The residue was purified by silica gel chromatography (n-hexane:ethyl acetate=1:1→1:3) to obtain the title compound (1.14 g) having the following physical properties.

1. washThe aqueous layer was washed twice with dichloromethane (100 mL) The combined organic layer
2. washwas washed with saturated sodium chloride solution (50 mL)
3. dry with materialdried over anhydrous magnesium sulfate
4. customAfter removing the anhydrous magnesium sulfate
5. filtrationby filtration
6. concentrationthe filtrate was concentrated
7. customThe residue was purified by silica gel chromatography (n-hexane:ethyl acetate=1:1→1:3)