Acetic Acid → HCID 57956919, compound

Temperature

-78 °C

A solution of dimethyl methylphosphonate (3.06 mL, 28.27 mmol, 8.0 eq) in anhydrous THF (30 mL) was cooled to −78° C. and 2.5 N n-BuLi (2.66 mL, 28.60 mmol, 8.0 eq) was added dropwise. After addition, the solution was stirred at −78° C. for 30 min and then a solution of compound 1 (1.00 g, 3.53 mmol, 1.0 eq) in anhydrous THF (20 mL) was added slowly. The resulting mixture was stirred at −78° C. for 1 h and then at ambient temperature for 1 h. The solution was acidified with 10% AcOH (20 mL), extracted with EtOAc (3×50 mL). The extract was washed with 10% NaHCO3, brine, dried over anhydrous MgSO4 and evaporation of the solvent gave a crude residue, which was subjected to column chromatography on silica gel elution with 100% EtOAc afforded dimethyl [(3S)-3-[(N-benzoyl)amino]-2-oxo-4-phenyl-butyl]phosphonate 2 as a pale yellow oil (0.876 g, 66%): Rf 0.34 (EtOAc); 1H NMR (300 MHz, CDCl3) δH 3.10 (2H, m, —CH2Ph), 3.34 (2H, m, —CH2—), 3.69 and 3.73 (6H, 2xs, 2xOMe), 5.10 (1H, m, —CH—) and 7.18-7.82 (10H, m, Ar—H).

1. additionAfter addition
2. stirringThe resulting mixture was stirred at −78° C. for 1 h
3. waitat ambient temperature for 1 h
4. extractionextracted with EtOAc (3×50 mL)
5. washThe extract was washed with 10% NaHCO3, brine
6. dry with materialdried over anhydrous MgSO4 and evaporation of the solvent
7. customgave a crude residue, which
8. washwas subjected to column chromatography on silica gel elution with 100% EtOAc

ORD record

ord-40100073928d4a9e98d151a348efa878

Source dataset

uspto-grants-2011_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07951834B2