1,4-Dichloro-cis-2-butene → HCID 18786343, compound

To a stirred solution of methyl 5-fluoro-3-methoxyphenylacetate (708 mg, 3.6 mmol) in THF (10 ml) was added a 1.0 M solution of potassium t-butoxide in THF (4.0 ml, 4.0 mmol) at -30° C. over 0.25 hr. After stirring for 1 h at the same temperature, a solution of cis-1,4-dichlorobut-2-ene (526 mg, 4.0 mmol) in THF (2 ml) was added dropwise and the reaction mixture was warmed to room temperature over 2 hr period. The reaction mixture was cooled to -30° C., and 1.0 M solution of potassium t-butoxide in THF (4.0 ml, 4.0 mmol) was added and the mixture was stirred overnight at room temperature. The reaction was quenched by the addition of saturated aqueous ammonium chloride solution and extracted with ethyl acetate. The combined extracts were washed with brine, dried with MgSO4 and concentrated in vacuo. Purification by column chromatography (SiO2, 150 g; hexane/ethyl acetate (20/1)) afforded 495 mg (55%) of methyl 1-(5-fluoro-3-methoxyphenyl)cyclopent-3-ene-1-carboxylate as a colorless oil.

1. temperatureThe reaction mixture was cooled to -30° C.
2. stirringthe mixture was stirred overnight at room temperature
3. customThe reaction was quenched by the addition of saturated aqueous ammonium chloride solution
4. extractionextracted with ethyl acetate
5. washThe combined extracts were washed with brine
6. dry with materialdried with MgSO4
7. concentrationconcentrated in vacuo
8. customPurification by column chromatography (SiO2, 150 g; hexane/ethyl acetate (20/1))

ORD record

ord-757d3ca3b51242b09d4737faf94e1cdb

Source dataset

uspto-grants-2000_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06063928