Triethylamine → methyl N-[(3-methyl-4'-nitrobiphenyl-4-yl)carbonyl]-L-valinate

Temperatur

50 °C

3-Methyl-4′-nitrobiphenyl-4-carboxylic acid (0.50 g, 1.0 mmol) was dissolved in methylene chloride (10 mL), and then oxalyl chloride (0.25 mL, 0.29 mmol) was added, followed by one drop of DMF. The resulting mixture was stirred at 50° C. for 45 min and then concentrated under reduced pressure. The residue was dissolved in methylene chloride (5 mL) and added dropwise to an ice-cold mixture of L-valine methyl ester hydrochloride (0.39 g, 2.3 mmol), methylene chloride (10 mL), and triethylamine (1.08 mL, 7.75 mmol). The resulting solution was stirred at rt for 18 h. The mixture was concentrated under reduced pressure, and the residue was purified by column chromatography (50% EtOAc in hexanes). This yielded 0.653 g (91%) of the title compound. LC/MS m/z 370.9 (MH+), retention time 3.29 min. 1H NMR (400 MHz, CD2Cl2) δ 1.06 (dd, 6H), 2.32-2.39 (m, 1H), 2.55 (s, 3H), 3.78 (s, 3H), 4.71-4.78 (m, 1H), 6.33 (d, 1H), 7.42-7.52 (m, 3H), 7.82 (d, 2H), 8.26 (d, 2H).

1. concentrationconcentrated under reduced pressure
2. dissolutionThe residue was dissolved in methylene chloride (5 mL)
3. stirringThe resulting solution was stirred at rt for 18 h
4. concentrationThe mixture was concentrated under reduced pressure
5. customthe residue was purified by column chromatography (50% EtOAc in hexanes)

ORD-Eintrag

ord-8049b03c4d65493cb15ed82af97fb676

Quelldatensatz

uspto-grants-2010_07

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07759376B2