L-Valine → HCID 14387464, compound

A mixture of L-valine (29.29 g, 250 mmol), and cyclohexanone (51.8 mL, 500 mmol, Aldrich Inc, Milwaukee, Wis.) was agitated in an atmosphere of hydrogen (pressure, 23.4-51.1 psi) at room temperature in 370 mL ethanol in the presence of Pd/C (20%, 3 g) until the absorption of hydrogen had ceased. The mixture was filtered, and this ethanolic filtrate was set aside, then the filter cake washed with 450 mL 1 M HCl. The ethanolic filtrate was concentrated to dryness and the residue dissolved in the aqueous filtrate above, which was treated with concentrated aqueous sodium hydroxide (29.8%) to adjust the pH to 5.5. The white solid precipitated out which was isolated via filtration, washed with two 150 mL portions of ethanol and dried under vacuum to give 37.4 g (70%) of the pure titled compound as a white solid; mp >300° C. APCI-MS m/z 200.2 (MH+).

1. filtrationThe mixture was filtered
2. washthe filter cake washed with 450 mL 1 M HCl
3. concentrationThe ethanolic filtrate was concentrated to dryness
4. dissolutionthe residue dissolved in the aqueous filtrate above, which
5. additionwas treated with concentrated aqueous sodium hydroxide (29.8%)
6. customThe white solid precipitated out which
7. customwas isolated via filtration
8. washwashed with two 150 mL portions of ethanol
9. customdried under vacuum

ORD record

ord-9c4b9d355ae54892968a2fdd43443c05

Source dataset

uspto-grants-2002_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06458781B1