Methyl iodide → (S)-Methyl 2-((tert-butoxycarbonyl)amino)-3-(4-nitrophenyl)propanoate

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Reaction Steps

To suspesion of of 4-nitro-N-[(1,1-dimethylethoxy)carbonyl]-L-phenylalanine (226.2 mmol, 70.2 g) and sodium carbonate (1.13 mol, 95 g) in DMF (500 mL) was added methyl iodide (1.13 mol, 70.4 InL) at room temperature. The suspesion was stirred for 15 h at room temperature at this time TLC analysis of the mixture indicated the absence of starting acid and the excess methyl iodide and some DMF were removed under high vacuum. The residue was poured into water (2 L) and stirred at room temperature as a precipitate formed slowly over 72 h. The precipitated solids were collected by filtration and washed with water (2 L). After air and vacuum drying, 72 g (98%) of a light yellow solid, mp 95-96° C. were obtained. 1H-NMR, (DMSO-d6) (400 MHz) δ 8.16 (d, 2H, J=20 Hz), 7.53 (d, 2H, J=20 Hz), 7.39 (d, 1H, J=22 Hz), 4.26-4.28 (m, 1H), 3.6 (s, 3H), 2.96-3.19 (m, 2H), 1.25 (s, 9H). 13C NMR, CDCl3 (100 Mhz) δ 172.04, 155.29, 146.27, 145.96, 130.48, 123.18, 78.36, 54.44, 51.9, 36.1, 27.99. HR MS: Obs. mass, 325.1404. Calcd. mass, 325.1400 (M+H).

Provenance & Evidence