反应详情

温度

60 °C

To a dimethylsulfoxide (22.5 ml) solution of the 2-(2-propyl-1,3-dioxolan-2-yl)ethanol (1.5 g, 9.35 mmol) obtained in the step (3b), sodium hydride, in oil (561 mg, 14 mmol as the content was regarded as 60%) and 4-chloro-2,3-dimethylpyridine1-oxide (1.33 g, 8.42 mmol) were added in a nitrogen stream and stirred at 60° C. for 2 hours. The mixture was allowed to stand at room temperature for 3 days and concentrated under reduced pressure. The residue was suspended in tetrahydrofuran. NH silica gel was added to the resultant mixture, which was then concentrated to dryness and subjected to NH silica gel column chromatography (elution solvent: n-heptane/ethyl acetate/methanol=1/1/0→0/1/0→0/10/1) to obtain the title compound (1.53 g, yield: 58.2%) as a light brown oil.

1. additionwere added in a nitrogen stream
2. waitto stand at room temperature for 3 days
3. concentrationconcentrated under reduced pressure
4. additionNH silica gel was added to the resultant mixture, which
5. concentrationwas then concentrated to dryness
6. washsubjected to NH silica gel column chromatography (elution solvent: n-heptane/ethyl acetate/methanol=1/1/0→0/1/0→0/10/1)