Hydrochloric Acid → Dimethyl 3-aminobenzene-1,2-dicarboxylate

Participants

Reaction Steps

A mixture of 3:1 ethanol-conc. HCl (200 mL) was cooled to 0° C. and then 3-nitrophthalic acid dimethyl ester (15.0 g, 62.8 mmol) was added. Maintaining the cooling, tin (II) chloride (70.8 g, 314 mmol) was added portionwise, over a period of 15 min. Following completion of the addition, the cooling bath was removed and stirring proceeded at room temperature. After 2 h, the mixture was neutralized by the addition of solid sodium bicarbonate, and the resulting mixture was extracted with ethyl acetate (3×150 mL) and the combined extracts were washed with water (5×250 mL), were dried (MgSO4) and evaporated, providing 11.3 g of 3-aminophthalic acid dimethyl ester as a yellow oil, in 86% yield; 1H NMR (CDCl3) δ 3.84 (s, 3H), 3.86 (s, 3H), 5.20 (br, 2H), 6.78 (dd, J=8.5 Hz, J=1.0 Hz, 1H), 6.90 (dd, 1H, J=7.3 Hz, J=1.0 Hz, 1H), 7.24 (t, J=7.8 Hz, 1H).

Provenance & Evidence