To a solution of N3-(3,5-dichlorophenyl)-1H-1,2,4-triazole-3,5-diamine Intermediate 2 (100 mg, 410 μmol) in MeOH (5 mL) was added N-tert-butyl-4-formylbenzenesulfonamide (109 mg, 451 μmol) followed by acetic acid (36.7 mg, 35 μl, 611 μmol). The reaction was stirred at room temperature for 15 minutes, 2-picoline borane complex (65.7 mg, 615 μmol) was added and the stirring was continued for 3 days. The reaction mixture was poured into 0.1N HCl solution (25 ml) and was extracted with EtOAc (3×30 ml). The combined organic solution was washed with brine, dried over Na2SO4 and concentrated to give a residue. The crude material was purified by flash chromatography (silica gel, 24 g, 3% to 5% MeOH in DCM) to give an off white solid as desired product (98 mg, 51% yield). MS +m/z: 469 (M+H)+
