反应详情

A solution of methyl 3-methyl-indazole-6-carboxylate (0.2 g, Reference Example 44) in acetone (15 ml) was treated with benzyl bromide (0.898 g) then with potassium carbonate (0.290 g) and a catalytic amount of 18-crown-6. The mixture was stirred for 12 hours at room temperature then poured into water (30 ml) and then extracted three times with ethyl acetate (30 ml). The combined extracts were dried over sodium sulphate then evaporated. The residue was subjected to flash chromatography on silica eluting with a mixture of ethyl acetate and hexane (7:1, v/v) to yield the title compound (0. 161 g) and methyl 2-benzyl-3-methyl-indazole-6-carboxylate (0.069 g).

1. extractionextracted three times with ethyl acetate (30 ml)
2. dry with materialThe combined extracts were dried over sodium sulphate
3. customthen evaporated
4. additionThe residue was subjected to flash chromatography on silica eluting with a mixture of ethyl acetate and hexane (7:1