反应详情

温度

100 °C

A mixture of 30.0 grams (84.9 mmol) of methyl 3-(2H-benzotriazol-2-yl)-5-tert-butyl-4-hydroxyhydrocinnamate, 19.1 grams (102 mmol) of 4-hydroxy-1-methoxy-2,2,6,6-tetramethylpiperidine, and 200 ml of xylene is heated at reflux in a round-bottomed flask equipped with a fractionating column and an adjustable still head. Approximately 25 ml of wet xylene is distilled from the reaction mixture. The reaction mixture is then cooled to 100° C., treated with 1.4 gram of lithium amide, and diluted with 100 ml of xylene. The mixture is heated at reflux for sixteen hours while methanol is removed by fractional distillation. The reaction mixture is diluted with 200 ml of toluene, and washed successively with 1N hydrochloric acid (200 ml) and saturated sodium bicarbonate solution (300 ml). Solids are removed by filtration, and the filtrate is dried over anhydrous magnesium sulfate and then concentrated to obtain a brown solid. The crude product is passed through a layer of silica gel (2:1 heptane:ethyl acetate). The eluent is evaporated to give a solid which is recrystallized from isopropanol to afford 24.5 grams (57% yield) of the title compound as a white solid melting at 135°-137° C.

1. temperatureis heated
2. temperatureat reflux in a round-bottomed flask
3. customequipped with a fractionating column
4. distillationApproximately 25 ml of wet xylene is distilled from the reaction mixture
5. additiontreated with 1.4 gram of lithium amide
6. additiondiluted with 100 ml of xylene
7. temperatureThe mixture is heated
8. temperatureat reflux for sixteen hours while methanol
9. customis removed by fractional distillation
10. additionThe reaction mixture is diluted with 200 ml of toluene
11. washwashed successively with 1N hydrochloric acid (200 ml) and saturated sodium bicarbonate solution (300 ml)
12. customSolids are removed by filtration
13. dry with materialthe filtrate is dried over anhydrous magnesium sulfate
14. concentrationconcentrated
15. customto obtain a brown solid
16. customThe eluent is evaporated
17. customto give a solid which
18. customis recrystallized from isopropanol