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Example 7: Synthesis of compound (II) Synthesis of methyl 1-[(2,6-difluorophenyl)methyl]-1H-1,2,3-triazole-4-carboxylate: 2,6-difluorobenzyl azide (3.0 g, 17.7 mmol) was suspended in ethanol (30 ml), followed by the addition of methyl propargylate (1.6 g, 19.6 mmol), ascorbic acid (317 mg, 1.8 mmol) and copper sulfate pentahydrate ( 50 mg, 0.18 mmol). The reaction mixture was stirred at 25°C overnight. After completion of the reaction, the mixture was concentrated, dissolved in ethyl acetate and the resulting solution was washed with ammonia. The organic phase was dried, filtered and concentrated under reduced pressure to give a white crystalline solid in 94% yield. 1H NMR (400 MHz, DMSO-d6) δ (ppm): 8.86 (s, 1H), 7.52 (m, 1H), 7.27-7.12 (m, 2H), 5.74 (s, 2H), 3.83 (s, 3H).