反応 #1049543

反応方程式

triphenylphosphine

1-O-octadecyl-2-O- benzyl-glycerol

toluene

carbon tetrabromide

→

1-O-octadecyl-2-O-benzyl-3-bromo-1,2-propanediol

溶媒

chloroform

反応条件

後処理

1. 1
   その他In a 250 ml round bottom flask equipped with a magnetic stir bar
2. 2
   workup.ADDITIONTo this solution were added 4.58 g
3. 3
   ろ過The yellow suspension was filtered
4. 4
   濃縮the filtrate concentrated on a rotary evaporator
5. 5
   その他to afford a white solid
6. 6
   洗浄washed twice with 30 ml saturated sodium bicarbonate
7. 7
   乾燥dried over anhydrous magnesium sulfate
8. 8
   濃縮concentrated under vacuum on a rotary evaporator
9. 9
   その他to afford 2.5 g of the crude product as a white powder
10. 10
    その他This crude product was purified by flash column chromatography on a silica gel 60 (E. Merck, Germany) column by sequential elution with 100 ml each of hexane, 1% ethyl acetate in hexane, 2% ethyl acetate in hexane and finally with 3% ethyl acetate in hexane
11. 11
    その他Fractions collected
12. 12
    濃縮The pooled fractions were concentrated under vacuum on a rotary evaporator

実験手順

In a 250 ml round bottom flask equipped with a magnetic stir bar, 2.00 g (4.6 mmoles) of 1-O-octadecyl-2-O- benzyl-glycerol (Bachem, Switzerland) was dissolved into 120 ml of toluene. To this solution were added 4.58 g. (13.8 mmoles) of carbon tetrabromide and 3.62 g. (13.8 mmoles) of triphenylphosphine and the reaction mixture stirred for 4 hours at room temperature. The yellow suspension was filtered and the filtrate concentrated on a rotary evaporator to afford a white solid. This residue was dissolved into 50 ml chloroform, washed twice with 30 ml saturated sodium bicarbonate, dried over anhydrous magnesium sulfate and concentrated under vacuum on a rotary evaporator to afford 2.5 g of the crude product as a white powder. This crude product was purified by flash column chromatography on a silica gel 60 (E. Merck, Germany) column by sequential elution with 100 ml each of hexane, 1% ethyl acetate in hexane, 2% ethyl acetate in hexane and finally with 3% ethyl acetate in hexane. Fractions collected were screened by TLC and those fractions that contained pure product (silica gel, 5% ethyl acetate in hexane, Rf=0.56) were pooled. The pooled fractions were concentrated under vacuum on a rotary evaporator to afford a quantitative yield of the 1-O-octadecyl-2-O-benzyl-3-bromo-1,2-propanediol as a white powder.

出典