Triethylamine → Ethyl 3-(4-fluorophenyl)propiolate

Temperature

0 °C

Prepared in analogy to Synthesis Communications (1989) 3:217-218. To a solution of triphenylphosphine oxide (3.77 g, 14 mmol) in 1,2-dichloroethane (42 mL) was added trifluoromethanesulfonic anhydride (2.25 mL, 14 mmol) dropwise at 0° C. and the grey suspension was stirred at 0° C. for 15 min. Then a solution of 3-(4-fluoro-phenyl)-3-oxo-propionic acid ethyl ester (2.85 g, 14 mmol) in 1,2-dichloroethane (14 mL) was added followed by a dropwise addition of triethylamine (3.78 mL, 28 mmol) at 0° C. The brown solution was refluxed for 2.5 h. After cooling the mixture was poured onto ice-water and the organic layer separated and washed with brine, dried over sodium sulphate, filtered and evaporated. Purification by chromatography (silica, 0 to 20% ethyl acetate in heptane) afforded the title compound (1.53 g, 59%) as a yellow solid. MS: m/e=193.2 [M+H]+.

1. customPrepared in analogy to Synthesis Communications (1989) 3:217-218
2. temperatureThe brown solution was refluxed for 2.5 h
3. temperatureAfter cooling the mixture
4. additionwas poured onto ice-water
5. customthe organic layer separated
6. washwashed with brine
7. dry with materialdried over sodium sulphate
8. filtrationfiltered
9. customevaporated
10. customPurification by chromatography (silica, 0 to 20% ethyl acetate in heptane)

ORD record

ord-3e7d0e5a59c5465ea553c0d0ec971e3e

Source dataset

uspto-grants-2014_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08742097B2