反应详情

A solution of 100.0 grams (64 mmol) of 4-amino-2,2,6,6-tetramethylpiperidine in 150 ml of toluene and a solution of 65.4 grams (64 mmol) of acetic anhydride in 175 ml of toluene are simultaneously added over a 45-minute period to a flask containing 150 ml of toluene. The reaction temperature is maintained at 25°-35° C. by using an ice water bath. The reaction mixture is stirred for 30 minutes after the addition is complete. Solids are separated by filtration, washed with ether and dissolved in 500 ml of water. This aqueous solution is added to a solution of 28 grams of sodium hydroxide in 100 ml of water. A crude solid is isolated by filtration and the filtrate is saturated with solid sodium chloride to precipitate more of the product. The solids are combined, dried and dissolved in warm isopropanol. The alcohol solution is filtered to remove salts, and the filtrate is concentrated to give an oil. The oil is crystallized from heptane to afford 111.0 grams (87% yield) of the title compound as a white solid melting at 100°-102° C.

1. temperatureThe reaction temperature is maintained at 25°-35° C.
2. additionafter the addition
3. customSolids are separated by filtration
4. washwashed with ether
5. dissolutiondissolved in 500 ml of water
6. additionThis aqueous solution is added to a solution of 28 grams of sodium hydroxide in 100 ml of water
7. customA crude solid is isolated by filtration
8. customto precipitate more of the product
9. customdried
10. dissolutiondissolved in warm isopropanol
11. filtrationThe alcohol solution is filtered
12. customto remove salts
13. concentrationthe filtrate is concentrated
14. customto give an oil
15. customThe oil is crystallized from heptane