To a solution of ethyl 3-(thiazol-2-yl)-1H-1,2,4-triazole-5-carboxylate (Intermediate-2, 1.7 mmol) in DMF (8 mL) was added sodium hydride (1.2 equiv). After 10 min, 1-(bromomethyl)-2-fluorobenzene (1.2 equiv) was added. The reaction was stirred at ambient temperature for 35 min. The reaction mixture was poured into water and extracted with EtOAc. The organic phases were washed with water and brine, dried over Na2SO4, filtered and conc. The crude product was purified using SiO2 chromatography and an appropriate solvent gradient (EtOAc/hexanes) to give ethyl 1-(2-fluorobenzyl)-5-(thiazol-2-yl)-1H-1,2,4-triazole-3-carboxylate (48%) and ethyl 1-(2-fluorobenzyl)-3-(thiazol-2-yl)-1H-1,2,4-triazole-5-carboxylate as white solids (44% yield).
