反应详情

温度

50 °C

112 g of naphthohydroquinone and 560 ml of n-decanol were placed in a 1 l three-necked flask and 56 ml of concentrated sulfuric acid was dropwisely added thereto for 30 minutes under nitrogen gas stream while stirring. Thereafter, the mixture was further stirred for 30 minutes and, then, heated at 50° C. for 1 hour and 30 minutes. After cooling, ethyl acetate-water was added to the reaction mixture and the precipitated crystals were filtered off. An aqueous sodium hydroxide solution was added to the filtrate so as to water layer reach pH of 5 to 6. Then, the ethyl acetate layer was washed with water and dried with MgSO4 overnight. The dried ethyl acetate solution was evaporated under reduced pressure to remove ethyl acetate and n-decanol. The residue was dissolved in 1 l of ethyl acetate and treated with 26 g of active carbon followed by concentration under reduced pressure. The residue was recrystallized from a mixed solvent of ethyl acetate and n-hexane and, further, recrystallized from benzene to obtain 73 g of white crystals having a melting point of 89° to 90° C.

1. stirringThereafter, the mixture was further stirred for 30 minutes
2. temperatureAfter cooling
3. filtrationthe precipitated crystals were filtered off
4. additionAn aqueous sodium hydroxide solution was added to the filtrate so as to water layer
5. washThen, the ethyl acetate layer was washed with water
6. dry with materialdried with MgSO4 overnight
7. customThe dried ethyl acetate solution was evaporated under reduced pressure
8. customto remove ethyl acetate and n-decanol
9. dissolutionThe residue was dissolved in 1 l of ethyl acetate
10. additiontreated with 26 g of active carbon
11. concentrationfollowed by concentration under reduced pressure
12. customThe residue was recrystallized from a mixed solvent of ethyl acetate and n-hexane
13. customfurther, recrystallized from benzene