Ethyl propiolate → HCID 18358858, compound

Temperature

-70 °C

To a solution of ethyl propiolate (4.05 mL, 40 mmol) in tetrahydrofuran (125 mL) at -78° C. under nitrogen was added n-BuLi (2.5 mL, 40 mmol, 1.6M in hexane). The reaction mixture was stirred at about -70° C. for 0.5 hours and then 2-nitro-5-chlorobenzaldehyde (6.75 g, 36.4 mmol) was added dropwise. The reaction mixture was stirred at -78° C. for 0.25 hours, warmed to -60° C., quenched with acetic acid (5 mL) and then warmed to room temperature. The reaction mixture was partitioned between ether (250 mL) and water (250 mL). The layers were separated and the organic layer was washed with brine (250 mL) and dried over Na2SO4. The mixture was filtered and the filtrate was concentrated in vacuo. The residue was purified by flash chromatography eluting with hexane/ethyl acetate (4:1) to afford 6.12 g (59%) of the title compound as a yellow oil which solidified on standing.

1. stirringThe reaction mixture was stirred at -78° C. for 0.25 hours
2. temperaturewarmed to -60° C.
3. customquenched with acetic acid (5 mL)
4. temperaturewarmed to room temperature
5. customThe reaction mixture was partitioned between ether (250 mL) and water (250 mL)
6. customThe layers were separated
7. washthe organic layer was washed with brine (250 mL)
8. dry with materialdried over Na2SO4
9. filtrationThe mixture was filtered
10. concentrationthe filtrate was concentrated in vacuo
11. customThe residue was purified by flash chromatography
12. washeluting with hexane/ethyl acetate (4:1)

ORD record

ord-3d84b06cf7d94bbd856f096ba6ad878b

Source dataset

uspto-grants-2000_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06124281