反应 #9055

反应方程式

2,3-diaminotoluene

trimethylorthoformate

trifluoroacetic acid

→

4-methyl-1H-benzimidazole

溶剂

CH2Cl2

CH2Cl2

反应条件

后处理

1. 1
   洗涤washed consecutively with saturated aqueous NaHCO3 (40 mL) and H2O (40 mL)
2. 2
   干燥The combined organic extracts were dried over MgSO4
3. 3
   浓缩concentrated to a rusty brown solid (1.07 g, 97%)

实验过程

To a stirred solution of 2,3-diaminotoluene (1.00 g, 8.2 mmol) in CH2Cl2 (82 mL) was added trimethylorthoformate (4.5 mL, 41 mmol) and trifluoroacetic acid (0.32 mL, 4.1 mmol) and the mixture stirred at room temperature for 24 h after which the reaction mixture was diluted with CH2Cl2 (200 mL), and washed consecutively with saturated aqueous NaHCO3 (40 mL) and H2O (40 mL). The aqueous layers were reextracted with CH2Cl2 (2×100 mL). The combined organic extracts were dried over MgSO4 and concentrated to a rusty brown solid (1.07 g, 97%). 1H NMR (300 MHz, CDCl3) δ 8.08 (s, 1H), 7.49 (d, 1H, J=8.1 Hz), 7.23–7.18 (m, 1H), 7.10 (d, 1H, J=7.5 Hz), 2.64 (s, 3H).

来源