Hydrochloric Acid → 3-Amino-5-fluoro-2-{4-[(methoxycarbonyl-methyl-amino)-methyl]-phenylethynyl}-benzoic acid methyl ester

Participants

Reaction Conditions

Reaction Steps

The crude compound 9 (140 g) was dissolved in methanol (1.05 L). Iron powder (325 mesh, 76.2 g, 1.36 mol) was added followed by addition of saturated aqueous ammonium chloride (210 ml). The solution was heated to 65° C. Aqueous hydrochloric acid (16 wt %, 32 ml) was added. The reaction was heated at 65° C. for 2 hours. HPLC analysis indicated the completion of the reaction. The reaction mixture was cooled to room temperature. Solid was removed by filtration. The filter cake was washed with methanol (2 L). The combined methanol solution was concentrated to dryness. The residue was partitioned between ethyl acetate (800 ml) and diluted aqueous hydrochloric solution (0.5 M, 300 ml). Organic layer was separated. Aqueous layer was extracted with ethyl acetate (3×200 ml). The combined organic solution was washed with brine (200 ml). The solution was then concentrated to dryness to afford 122.8 g of crude product as dark oil. This crude product was used in the next step without further purification. 1H NMR (300 MHz, CDCl3) δ 2.87 (d, br, 3H), 3.491 (s, 3H), 3.932 (s, 3H), 4.486 (s, br, 2H), 6.60 (dd, 1H, J=2.7 Hz and J=9.9 Hz), 7.04 (dd, 1H, J=2.4 Hz and J=9.0 Hz), 7.237 (s, br, 2H), 7.52 (d, 2H, J=8.1 Hz).

Provenance & Evidence