反应详情

4-Fluoro-2-[[(4-methoxy-2-pyridinyl)methyl]sulfinyl]-1H-benzimidazole (1.6 g, 5.2 mmol) was suspended in methylene chloride (50 ml). Methanol was added until a clear solution was obtained. The mixture was concentrated on a rotavapor under reduced pressure. The oily residue, which was not allowed to crystallize, was dissolved in methylene chloride (30 ml). A solution of formaldehyde (5 M, 10 ml, 50 mmol) was added and the mixture was stirred violently for four minutes. After separation the organic solution was dried (Na2SO4) and concentrated until 10 ml of the mixture was left. The flask was chilled for 15 minutes whereupon the formed precipitate was filtered off and washed with cold methylene chloride. In this way the title compound was obtained (1.1 g, 63%). NMR data is given below.

1. customwas obtained
2. concentrationThe mixture was concentrated on a rotavapor under reduced pressure
3. customto crystallize
4. dissolutionwas dissolved in methylene chloride (30 ml)
5. customAfter separation the organic solution
6. dry with materialwas dried (Na2SO4)
7. concentrationconcentrated until 10 ml of the mixture
8. waitwas left
9. temperatureThe flask was chilled for 15 minutes whereupon the formed precipitate
10. filtrationwas filtered off
11. washwashed with cold methylene chloride