反应详情

A solution of 2-formylphenyl 4-(trifluoromethyl)benzenesulfonate (6.5 g, 19.7 mmol) in ethanol (100 ml) is added to a solution of 4-imidazoleacetic acid hydrazide (18 mmol) in ethanol (200 mL). A catalytic amount of HCl in dioxane (3 mL) is added and the mixture is stirred at room temperature overnight. The precipitate that forms is removed by filtration. The filtrate is concentrated and chromatographed on silica eluting with 5% (2M ammonia in methanol)/CH2Cl2 to give 2-((E)-{2-[2-(1H-imidazol-4-yl)acetyl]hydrazono}methyl)phenyl 4-(trifluoromethyl)benzenesulfonate as a white solid. The yield is 3.1 g, 38%. 1H NMR (400 MHz, DMSO) d 11.94 (s, 1H), 11.48 (2s, 1H), 8.02 (m, 6H), 7.21 (m, 5H), 3.64 (2 s, 2H). ESI+ for C19H15F3N4O4S, m/z 453, (M+H)+.

1. customThe precipitate that forms is removed by filtration
2. concentrationThe filtrate is concentrated
3. customchromatographed on silica eluting with 5% (2M ammonia in methanol)/CH2Cl2