Ethyl propiolate → HCID 18697750, compound

Temperature

-60 °C

A 1.0 M solution (9.49 ml) of lithium bistrimethylsilylamide in tetrahydrofuran was added to tetrahydrofuran (20.0 ml) at -78° C. under an argon atmosphere, and the mixture was stirred for 30 min. A solution of ethyl propiolate (0.78 ml, 8.62 mmol) in tetrahydrofuran (2.0 ml) was added thereto, and the mixture was stirred for 30 min. A solution of 4-t-butoxycarbonylamino-2-nitrobenzaldehyde (1.53 g, 5.75 mmol) in tetrahydrofuran (20 ml) was then added thereto, and the temperature was raised to -60° C., followed by stirring for 30 min. This reaction mixture was poured into an ice-cold 10% aqueous ammonium chloride solution, and the mixture was vigorously stirred for 5 min. The reaction mixture was extracted with ethyl acetate, and the organic layer was washed with saturated brine and dried over anhydrous magnesium sulfate. The solvent was removed under reduced pressure to give ethyl 4-(4-t-butoxycarbonylamino-2-nitrophenyl)-4-hydroxy-2-butynoate as an oil (693 mg, 33%).

1. stirringthe mixture was stirred for 30 min
2. stirringby stirring for 30 min
3. stirringthe mixture was vigorously stirred for 5 min
4. extractionThe reaction mixture was extracted with ethyl acetate
5. washthe organic layer was washed with saturated brine
6. dry with materialdried over anhydrous magnesium sulfate
7. customThe solvent was removed under reduced pressure

ORD record

ord-c56736c46276432090a72bcea73b4329

Source dataset

uspto-grants-2000_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06093714