Water → Diethyl [2,3,4-trifluoro[(1S)-2-hydroxy-1-methylethyl]anilino]methylenemalonate

Temperature

0 °C

At room temperature, potassium hydroxide (330 mg) and tetrabutylammonium hydrogensulfate (82.7 mg) were dissolved in DMF (15 ml). After adding a solution (5 ml) of (2S)-2-(2,3,4-trifluoroanilino)propanol (1 g, 99.8% ee) and diethyl ethoxymethylenemalonate (2.09 g) in DMF, the resultant mixture was stirred for 1 hour. After adding water, the liquid reaction mixture was extracted with a solvent mixture of ethyl acetate and n-hexane (3:2). The organic layer was washed with water and dried over anhydrous magnesium sulfate. After evaporating the solvent, IPE was added to the obtained residue and the mixture was stirred at 0° C. for 1 hour. The crystals thus precipitated were collected by filtration and the moist product thus obtained was dried under reduced pressure. Thus, the title compound (1.65 g, 99.8% ee) was obtained as colorless crystals. The 1H-NMR and IR spectral data of this product was identical with those of the compound obtained in Example 63.

1. customthe liquid reaction mixture
2. extractionwas extracted with a solvent mixture of ethyl acetate and n-hexane (3:2)
3. washThe organic layer was washed with water
4. dry with materialdried over anhydrous magnesium sulfate
5. customAfter evaporating the solvent, IPE
6. additionwas added to the obtained residue
7. customThe crystals thus precipitated
8. filtrationwere collected by filtration
9. customthe moist product thus obtained
10. customwas dried under reduced pressure

ORD record

ord-25d9fb72cda44c2d9ff6078712d9cbc8

Source dataset

uspto-grants-2005_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06872823B1