反应详情

5,6-Dimethoxybenzimidazole (470 mg, 2.64 mmol) was added to a suspension of NaH (60% in mineral oil, 112 mg, 2.8 mmol) in NMP (5 ml) at <5° C. The mixture was stirred for 20 min, then a solution of 2-chloro-4-phenylthiazole-5-carboxylic acid ethyl ester (589 mg, 2.2 mmol) in NMP (1.5 ml) was added over 2-3 min. The mixture was stirred 2.5 hrs at RT. Water (15 ml) was added and stirred for 20 min. Solid was collected by filtration to provide the product 2-(5,6-dimethoxy-benzoimidazol-1-yl)-4-phenylthiazole-5-carboxylic acid ethyl ester (753 mg. Yield 84%). 1H-NMR (300 MHz, CDCl3) 8.44(s, 1H); 7.87-7.90(m, 2H); 7.72(2, 1H); 7.44-7.49(m, 3H); 7.30(s, 1H); 4.32(q, J=Hz, 2H); 3.98(s, 3H); 3.97(s, 3H); 1.33(t, J=Hz, 3H). MS M/z 410(M+1).

1. stirringThe mixture was stirred 2.5 hrs at RT
2. stirringstirred for 20 min
3. filtrationSolid was collected by filtration