Reacción #309152

Ecuación de reacción

sodium bicarbonate

3-chloro-2-chloromethyl-1-propene

ethyl (4-bromophenyl)acetate

LHMDS

→

ethyl 2-(4-bromophenyl)-4-(chloromethyl)pent-4-enoate

Ethyl 2-(4-bromophenyl)-4-(chloromethyl)pent-4-enoate

Disolventes

THF

THF

Condiciones de reacción

Tratamiento posterior

1. 1
   Temperaturato slowly warm from −78° C. to rt over 15 hours
2. 2
   Extracciónextracted with EtOAc
3. 3
   Secadodried over sodium sulfate
4. 4
   Filtraciónfiltered
5. 5
   Concentraciónconcentrated
6. 6
   OtroThe crude residue was purified by column chromatography
7. 7
   Lavadoeluting with 1-20% EtOAc/Hexane
8. 8
   Otrothe solvent removed in vacuo

Procedimiento

To a solution of ethyl (4-bromophenyl)acetate (143 g, 588 mmol) in THF (800 mL) was added LHMDS (1.13 eq in THF) at −78° C. After 30 minutes, the reaction mixture was added to a solution of 3-chloro-2-chloromethyl-1-propene (147 g, 1180 mmol) in THF (500 mL) at −78° C. via cannula. The reaction was allowed to slowly warm from −78° C. to rt over 15 hours. The reaction mixture was poured into sodium bicarbonate, extracted with EtOAc, dried over sodium sulfate, filtered and concentrated. The crude residue was purified by column chromatography eluting with 1-20% EtOAc/Hexane. The appropriate fractions were combined and the solvent removed in vacuo to give ethyl 2-(4-bromophenyl)-4-(chloromethyl)pent-4-enoate (1-1) as a clear oil. MS (M+H)+: 332.

Fuente