Methyl 6-chloro-5-nitronicotinate → (S)-methyl 6-((1-ethoxy-1-oxopropan-2-yl)(isopropyl)amino)-5-nitronicotinate

(S)-ethyl 2-(isopropylamino)propanoate (2.83 g, 17.8 mmol) was added to methyl 6-chloro-5-nitronicotinate (1.72 g, 7.94 mmol) and the reaction mixture was stirred in a closed vial at 90° C. for 20 h. It was cooled and diluted with EtOAc (25 mL). The resulting precipitate was filtered off, the filtrate was concentrated in vacuo and purified using flash column chromatography on silica gel (220 g SiO2, hexanes:ethyl acetate 4:1) to afford the title compound as yellow oil (1.12 g, 42%). 1H NMR (400 MHz, CHLOROFORM-d) δ (ppm): 1.18 (t, J=7.07 Hz, 3H) 1.30 (d, J=6.32 Hz, 3H) 1.36 (d, J=6.57 Hz, 3H) 1.66 (d, J=6.82 Hz, 3H) 3.48-3.62 (m, 1H) 3.90 (s, 3H) 4.03 (q, J=6.65 Hz, 1H) 4.06-4.21 (m, 2H) 8.54 (d, J=2.02 Hz, 1H) 8.70 (d, J=2.02 Hz, 1H); [M+H] calc'd for C15H21N3O6, 340; found, 340.