反应详情

50 g of methyl (R)-3-hydroxytetradecanoate, 35 g of t-butyldimethylchlorosilane, 6.1 g of 4-dimethylaminopyridine and 29.4 g of triethylamine were dissolved in 200 ml of methylene chloride and stirred at room temperature for 30 hours as well as under reflux for 16 hours. Thereupon, a further 2 g of t-butyldimethylchlorosilane were added. After a further 24 hours under reflux the precipitated triethylamine hydrochloride salt was filtered off, washed with ether and the filtrate was concentrated. The residue was dissolved in ether and washed in sequence with water, 0.5M citric acid, again with water and saturated sodium chloride solution, dried, concentrated and subsequently freed from volatile material at 5° C. in a high vacuum for 5 hours. There were obtained 71.8 g of (R)-3-[(1,1-dimethylethyl)dimethylsilyloxy]tetradecanoic acid, IR (cm-1): 1745, 1254, 895, 776.

1. temperatureunder reflux for 16 hours
2. filtrationwas filtered off
3. washwashed with ether
4. concentrationthe filtrate was concentrated
5. dissolutionThe residue was dissolved in ether
6. washwashed in sequence with water, 0.5M citric acid, again with water and saturated sodium chloride solution
7. customdried
8. concentrationconcentrated
9. waitsubsequently freed from volatile material at 5° C. in a high vacuum for 5 hours