Hydrochloric Acid → HCID 14358765, compound

To a solution of 2-hydroxy-3-methylbutanoic acid (5.0 g, 42.3 mmol) in DMF (21.2 mL) at 0° C. were added imidazole (6.34 g, 93.0 mmol) and DMAP (1.55 g, 12.7 mmol). The mixture was stirred for 5 min and TBDMS-Cl (14.0 g, 93.0 mmol) was added. The mixture was allowed to warm to ambient temperature. After 18 h, HCl (1.0 M in water) was added and the mixture was extracted with ethyl ether. The organic layer was washed with sat. NaHCO3, brine, dried over MgSO4, filtered and concentrated. The crude product was dissolved in THF (25 mL) and a solution of KOH (7.12 g, 127 mmol) in THF (130 mL) and water (40 mL) was added at 0° C. The mixture was stirred for 1 h. The solution was acidified and the mixture was extracted with ethyl acetate (5×). The combined organic extracts was dried over MgSO4, filtered and concentrated. Purification by silica gel chromatography (100% hexanes→60% hexanes/ethyl acetate) gave the title compound (4.44 g).

1. waitAfter 18 h
2. extractionthe mixture was extracted with ethyl ether
3. washThe organic layer was washed with sat. NaHCO3, brine
4. dry with materialdried over MgSO4
5. filtrationfiltered
6. concentrationconcentrated
7. dissolutionThe crude product was dissolved in THF (25 mL)
8. stirringThe mixture was stirred for 1 h
9. extractionthe mixture was extracted with ethyl acetate (5×)
10. dry with materialThe combined organic extracts was dried over MgSO4
11. filtrationfiltered
12. concentrationconcentrated
13. customPurification by silica gel chromatography (100% hexanes→60% hexanes/ethyl acetate)

ORD record

ord-a12c8f7f49414829bb609fb692820377

Source dataset

uspto-grants-2015_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08946231B2