5-Chloro-2-nitrobenzoic acid → 3-Amino-5-chloro-2-nitrobenzoic acid

Beteiligte Stoffe

Reaktionsschritte

Under nitrogen, to a solution of t-BuOK (156.8 g) and Cu(OAc)2 (3.6 g) in DMF (1.2 L) was added a solution of 5-chloro-2-nitrobenzoic acid (40.0 g) and MeONH2HCl (33.2 g) in DMF (300 mL) at 0° C. After 3 h the reaction was quenched by addition of H2O (2.5 L) and acidified with 10% HCl solution to pH=1. The mixture was extracted with EA (2 L×2) and the combined organic layers were then washed with brine, dried over anhydrous Na2SO4, filtered and concentrated in-vacuo to afford the crude product as a yellow solid (43.2 g, yield 100%). 1H NMR (300 MHz, CDCl3): δ ppm 6.88 (s, 1H, J=2.4 Hz), 6.91 (d, 1H, J=2.4 Hz), 8.08 (br s, 2H); LC-MS: m/e=217 [M+1]+.

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