Acetic Anhydride → 7-O-(Triethylsilyl) Baccatin III

Participants

Reaction Conditions

Reaction Steps

182 g of triethylsilyl chloride are added over 1 hour 20 minutes to a solution of 293.9 g of 10-deacetylbaccatin III in 2.7 liters of pyridine. The solution obtained is stirred for 40 hours at 5° C. 360 g of acetic anhydride are then added while the temperature is maintained at 5° C. The suspension obtained is stirred for 48 hours at 20° C. and then poured into 40 liters of ice-cold water. The precipitate obtained is separated by filtration, then washed with 8 times 2 liters of water and lastly dissolved in 3 liters of ethyl acetate. The organic phase is dried over magnesium sulphate. After filtration and concentration under reduced pressure, the product obtained is crystallized in isopropyl ether. 7-(Triethylsilyl)baccatin III is thereby obtained in a 77% yield, the characteristics of which product are as follows:

Provenance & Evidence