反应详情

A mixture of 320 mg of (2S,3R)-2-octyl-1,3-butanediol, 193 mg of p-hydroxybenzaldehyde, 0.1 ml of 1N sulfuric acid and 20 ml of toluene was placed under nitrogen in a round flask having a magnetic stirrer, water separator and condenser. The mixture was heated to reflux for 3 hours while separating water. The cooled reaction mixture was poured into aqueous sodium hydrogen carbonate solution and treated with diethyl ether. The aqueous phase was separated and extracted three times with diethyl ether. The combined organic phases were washed three times with round flask having a magnetic stirrer, water separator and condenser. The mixture was heated to reflux for 3 hours while separating water. The cooled reaction mixture was poured into aqueous sodium hydrogen carbonate solution and treated with diethyl ether. The aqueous phase was separated and extracted three times with diethyl ether. The combined organic phases were washed three times with water, dried over magnesium sulfate, filtered and evaporated. Recrystallization of the yellowish, solid residue (480 mg) from hexane/ethyl acetate (vol. 25:1) gave 410 mg of 4-[(2S,4R,5S)-5-octyl-4-methyl-1,3-dioxan-2-yl]phenol as yellowish crystals with [a]D =+27° (c=1% in chloroform).

1. customwas placed under nitrogen in a round flask
2. temperatureThe mixture was heated
3. temperatureto reflux for 3 hours
4. customwhile separating water
5. customThe cooled reaction mixture
6. customThe aqueous phase was separated
7. extractionextracted three times with diethyl ether
8. washThe combined organic phases were washed three times with round flask
9. temperatureThe mixture was heated
10. temperatureto reflux for 3 hours
11. customwhile separating water
12. customThe cooled reaction mixture
13. customThe aqueous phase was separated
14. extractionextracted three times with diethyl ether
15. washThe combined organic phases were washed three times with water
16. dry with materialdried over magnesium sulfate
17. filtrationfiltered
18. customevaporated
19. customRecrystallization of the yellowish, solid residue (480 mg) from hexane/ethyl acetate (vol. 25:1)