反应详情

2,4-dimethoxybenzyl isocyanate (0.717 g, 4.4 mmol) was added drop wise to a suspension of 5-diazoimidazole-4-carboxamide (0.548 g, 4 mmol) in dry dimethylsulfoxide (5 mL) at room temperature under nitrogen. The resulting mixture was stirred at room temperature overnight. The reaction was quenched by the addition of ice and the solid product (purple) removed by filtration, washed with water and ethyl acetate and recrystallised from chloroform/hexane to give the title compound. Yield: 0.613 g, 46%. IR vmax/cm−1 3473, 3121, 1734, 1697, 1605, 1589. 1H NMR δH (DMSO-d6) 3.76 (3H, s, OMe), 3.80 (3H, s, OMe), 5.37 (2H, s, CH2Ar), 6.48 (1H, dd, J=8.4, 2.4, ArH), 6.60 (1H, d, J=2.4, ArH), 7.22 (1H, d, J=8.4, ArH), 7.68 (1H, br s, NH), 7.80 (1H, br s, NH), 8.81 (1H, s, 6-H). δC (DMSO-d6) 47.5, 55.8, 56.1, 98.9, 105.1, 115.9, 129.3, 130.7, 131.2, 134.8, 139.4, 158.5, 161.1, 162.0.

1. customThe reaction was quenched by the addition of ice
2. customthe solid product (purple) removed by filtration
3. washwashed with water and ethyl acetate
4. customrecrystallised from chloroform/hexane