反应详情

3,4,5-Trimethoxybenzyl isocyanate (Sigma Aldrich) (0.536 g, 2.4 mmol) was added drop wise to a suspension of 5-diazoimidazole-4-carboxamide (0.274 g, 2 mmol) in dry dimethylsulfoxide (2.5 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 removed by filtration, washed with water and ethyl acetate, and then recrystallised from chloroform/hexane to give an off-white powder. Yield: 0.323 g, 45%. IR vmax/cm−1 1740, 1690, 1589. 1H NMR δH (DMSO-d6) 3.64 (3H, s, 4-OMe), 3.76 (6H, s, 3,5-OMe), 5.42 (2H, s, CH2Ar), 6.75 (2H, s, ArH), 7.68 (1H, br s, NH), 7.81 (1H, br s, NH), 8.84 (1H, s, 6-H). δC (DMSO-d6) 52.5, 56.4, 60.4, 105.9, 129.4, 131.3, 131.7, 134.9, 137.6, 139.7, 153.4, 162.0. MS Found 361.1300. Calc for (M+H): 361.1260. Found C, 49.5; H, 4.4; N, 23.2. Calc. for C15H16N6O5C, 50.0; H, 4.5; N, 23.3%.

1. customThe reaction was quenched by the addition of ice
2. customthe solid product removed by filtration
3. washwashed with water and ethyl acetate
4. customrecrystallised from chloroform/hexane
5. customto give an off-white powder