2-Hydroxycarbamoyl-4-methylpentanoic acid → 2-(2,2-Dimethylpropionyloxycarbamoyl)-4-methylpentanoic acid

Temperature

0 °C

Intermediate (3d) (12.7 g, 73.2 mmol, 1.0 eq) was dissolved into 180 mL DCM and cooled to 0° C. DIPEA (13.4 mL, 76.9 mmol, 1.05 eq) was added, followed by pivaloyl chloride (9.5 mL, 76.9 mmol, 1.05 eq). The mixture was warmed to room temperature and stirred for 12 hours. The mixture was concentrated under reduced pressure, dissolved into 300 mL EtOAc, washed 2×200 mL 1M H3PO4, 100 mL saturated aqueous NaCl, dried over MgSO4, and evaporated. The material was triturated with hexanes, filtered and dried the to yield the title compound (10.5 g, 55%). 1H NMR (DMSO) δ (ppm): 0.7 (m, 6H), 1.2-1.4 (m, 1H), 1.4-1.6 (m, 2H), 2.9 (t, 1H), 3.3 (quart, 1H), 8.9 (br s, 1H), 10.5 (br s, 1H).

1. temperatureThe mixture was warmed to room temperature
2. concentrationThe mixture was concentrated under reduced pressure
3. dissolutiondissolved into 300 mL EtOAc
4. washwashed 2×200 mL 1M H3PO4, 100 mL saturated aqueous NaCl
5. dry with materialdried over MgSO4
6. customevaporated
7. customThe material was triturated with hexanes
8. filtrationfiltered
9. customdried the

ORD record

ord-8543ecb1c4174d94ae7e03cd22772a33

Source dataset

uspto-grants-2013_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08501798B2