反应 #1172896

反应方程式

ammonium chloride

n-Butyl lithium

2-[4-bromo-2,3,5,6-tetrafluorobenzyloxy]-tetrahydropyran

Z-1-chloro-3-iodoprop-1-ene

→

2-[4-(3-chloroprop-2-en-1-yl)-2,3,5,6-tetrafluorobenzyloxy]-tetrahydropyran

溶剂

tetrahydrofuran

tetrahydrofuran

反应条件

后处理

1. 1
   温度to warm to 0° C., for a period of 15 minutes
2. 2
   温度After cooling to -70° C.
3. 3
   workup.ADDITIONwas added to the reaction mixture, which
4. 4
   萃取was then extracted with ethyl acetate
5. 5
   其他After drying
6. 6
   其他the solvent was evaporated under reduced pressure
7. 7
   其他to give an orange oil
8. 8
   洗涤eluting with petroleum ether (boiling range 40°-60° C.)
9. 9
   workup.ADDITIONcontaining diethyl ether (5% by volume)

实验过程

n-Butyl lithium (2.5M in hexane, 3 cm3) was added portionwise to a solution of 2-[4-bromo-2,3,5,6-tetrafluorobenzyloxy]-tetrahydropyran (1.7 g) in dry tetrahydrofuran (10 cm3) under an atmosphere of dry nitrogen, whilst the reaction temperature was maintained at -70° C. After 30 minutes, copper (I) bromide--dimethyl sulphide complex (1.54 g) was added in one portion and the reaction temperature allowed to warm to 0° C., for a period of 15 minutes. After cooling to -70° C., a solution of Z-1-chloro-3-iodoprop-1-ene (2.03 g) in dry tetrahydrofuran (3 cm3) was added portionwise, and the reaction mixture stirred for a further hour at -70° C. After warming to the ambient temperature, (ca. 25° C.), aqueous ammonium chloride was added to the reaction mixture, which was then extracted with ethyl acetate. After drying, the solvent was evaporated under reduced pressure to give an orange oil. The residue was then subjected to medium pressure column chromaatography on a silica gel column using a Gilson apparatus, eluting with petroleum ether (boiling range 40°-60° C.) containing diethyl ether (5% by volume) to give 2-[4-(3-chloroprop-2-en-1-yl)-2,3,5,6-tetrafluorobenzyloxy]-tetrahydropyran, as a mixture consisting predominantly of the Z isomer.

来源