2,3-Dichloropropene → Ethyl 4-chloro-2,2-dimethylpent-4-enoate

Diisopropylamine (1.25 eq) was added to a reaction flask containing tetrahydrofuran (10.0-fold, V/W of ethyl isobutyrate) under nitrogen. The mixture was cooled to less than −70° C., and n-butyllithium (2.7M; 1.14 eq) was added to the reaction mixture while the temperature was maintained at less than −65° C. The reaction mixture was slowly warmed to room temperature and then stirred for 2 hours under nitrogen. The reaction mixture was then cooled to less than −70° C., and ethyl isobutyrate (1.0 eq) was added, followed by 2,3-dichloro-1-propene (1.09 eq), while the temperature was maintained at less than −70° C. The reaction was allowed to warm to room temperature and stirred overnight under nitrogen. The reaction was then quenched with ice water (10.0-fold, V/W of starting material), and the pH adjusted to pH 7 with aqueous 6M hydrochloric acid. The organic layer was separated, washed twice with brine, and dried over sodium sulfate. The solvent was removed in vacuo and the product was taken on to the next step without further purification.

1. temperatureThe mixture was cooled to less than −70° C.
2. temperaturewas maintained at less than −65° C
3. temperatureThe reaction mixture was then cooled to less than −70° C.
4. temperaturewas maintained at less than −70° C
5. temperatureto warm to room temperature
6. stirringstirred overnight under nitrogen
7. customThe reaction was then quenched with ice water (10.0-fold, V/W of starting material)
8. customThe organic layer was separated
9. washwashed twice with brine
10. dry with materialdried over sodium sulfate
11. customThe solvent was removed in vacuo
12. customthe product was taken on to the next step without further purification

ORD record

ord-9714d49083014ad3ae6526b2a1596c22

Source dataset

uspto-grants-2014_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08772495B2