2-Azidobenzoic acid

The solution of the corresponding 2-aminobenzoic acid (15.3 mmol) in water (15 mL) and conc. HCl (17 mL) was placed in a 200 mL beaker and cooled to 5 °C. To this mixture a precooled solution of sodium nitrite (1.06 g, 15.3 mmol in 10 mL water) was added drop wise with vigorous stirring. After stirring for 15 min, a solution of sodium azide (1.08 g, 16.6 mmol) in 10 mL water was added and the resulting mixture was gradually warmed to room temperature and stirred at this temperature for about 2 h. The white crystalline azides precipitated from the reaction mixture and were filtered off. After washing with cold water and drying in the dark at room temperature the azides were recrystallized from heptane/benzene (v/v, 1:1). 1H NMR (400 MHz, CDCl3) δ 10.65  (s, 1H), 8.11 (dd, J = 7.9, 1.5 Hz, 1H), 7.66 – 7.56 (m, 1H), 7.31 – 7.21 (m, 2H). 13C  NMR (101 MHz, CDCl3) δ 168.8, 140.4, 134.6, 133.4, 125.1, 120.9, 119.7.

2-Azidobenzoic Acid can be used for polyethylene surface with aryl azides.