Dimethylformamide → Methyl 3-carbamoyl-5-nitrobenzoate

Participants

Reaction Steps

A solution of mono-methyl 5-nitroisophthalate (45.0 g, 200 mmol), thionyl chloride (71.4 g, 600 mmol) and DMF through SiO2 (125 μL) in dry THF (100 mL) and dry CH2Cl2 (300 mL) was refluxed overnight. See, FIG. 1C, step 1. The reaction mixture was evaporated in vacuo and then added dry CH2 Cl2 (200 mL) and hexanes (500 mL). Ammonia gas was introduced into the solution and the precipitation was collected on a glass-filter. Id., step 2. The cake was suspended in 1N HCl (500 mL), filtered again and then washed with saturated NaHCO3 aq. (500 mL) and water (500 mL). The product was dried in vacuo to give ivory powder (36.3 g, 81%): 1H NMR (300 MHz, DMSO-d6) δ 8.918 (t, J=1.8 Hz, 1H), 8.816 (t, J=1.2 Hz, 1H), 8.773 (t, J=1.6 Hz, 1H), 8.716 (s, 1H, NH), 7.859 (s, 1H, NH), 3.944 (s, 3H); 13C NMR (300 MHz, DMSO-d6) δ 164.9, 164.2, 148.1, 136.4, 134.9, 133.8, 133.3, 131.5, 126.4, 126.0, 53.1.

Provenance & Evidence