2,3-Dichloropropene → HCID 13370940, compound

Temperature

-4 °C

A 1 liter flask was equipped with a mechanical stirrer, reflux condenser, nitrogen inlet, addition funnel, and thermometer. The flask was charged with 200 ml of tetrahydrofuran (THF) and 31.37 g (0.300 mol) of diisopropylamine and cooled to -4° C. The n-butyllithium solution (265 ml of 1.6M, 0.424 mol) was added dropwise at -4° to -6° C. over 22 minutes. The reaction mixture was then stirred for 30 minutes at -4° C. and then 39.06 g (0.300 mol) of ethyl isovalerate added over 15 minutes. The reaction mixture was cooled to -78° C. and 44.39 g (0.400 mol) of 2,3-dichloro-1-propene added dropwise. During the addition of the halide, the temperature was maintained at -78° C. to -74° C. The reaction mixture was stirred for 2 hrs. at -78° C. to give a clear, tan colored solution. The temperature of the reaction mixture was then allowed to rise to -40° C., and stirred at -40° C. to -30° C. for 2 hours. The reaction mixture was then allowed to stand at room temperature over the weekend. The reaction mixture was quenched with 25 ml of water and then poured into 300 ml of ice water. The aqueous mixture was extracted twice with 250 ml portions of ether. The combined ether extracts were washed with saturated sodium chloride solution, dried (MgSO4), and the ether removed. The residue was vacuum distilled through a vigreux column to give 28.02 g (46% yield) of ethyl 4-chloro-2-isopropyl-4-pentenoate, bp 53°-63° C./0.70 mm.

1. customA 1 liter flask was equipped with a mechanical stirrer
2. temperaturereflux
3. additioncondenser, nitrogen inlet, addition funnel
4. temperatureThe reaction mixture was cooled to -78° C.
5. temperaturethe temperature was maintained at -78° C. to -74° C
6. stirringThe reaction mixture was stirred for 2 hrs
7. customat -78° C. to give a clear, tan colored solution
8. customto rise to -40° C.
9. stirringstirred at -40° C. to -30° C. for 2 hours
10. customto stand at room temperature over the weekend
11. customThe reaction mixture was quenched with 25 ml of water
12. additionpoured into 300 ml of ice water
13. extractionThe aqueous mixture was extracted twice with 250 ml portions of ether
14. washThe combined ether extracts were washed with saturated sodium chloride solution
15. dry with materialdried (MgSO4)
16. customthe ether removed
17. distillationdistilled through a vigreux column

ORD record

ord-4a8b048dcaa344bdac578defe0a07d12

Source dataset

uspto-grants-1985_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04492799