反应详情

To a stirred room temperature solution of indole (5.9 g, 50 mmol) in THF (100 mL) was added sodium hydride (2.4 g of 60% in mineral oil, 60 mmol) in one portion. After 30 minutes, 4-chloromethyl-2,2-dimethyl-1,3-dioxolane (10.6 mL, 75 mmol) was added followed by tetra-n-butylammonium iodide (1.9 g, 5 mmol) and the mixture was warmed at reflux. After 24 hours, LCMS showed about 50% conversion [MS m/z 232 (MH+)]. Additional 4-chloromethyl-2,2-dimethyl-1,3-dioxolane (11.4 mL) was added and the refluxing continued. After 18 hours, the mixture was cooled, diluted with THF (300 mL), filtered, and concentrated in vacuo to afford a brown oil. The residue was purified by column chromatography over silica gel eluting with 0-100% methylene chloride in hexanes and the product-rich fractions were collected to afford 3.3 g of 1-(2,2-dimethyl-1,3-dioxolan-4-ylmethyl)-1H-indole as a brownish oil.

1. temperaturethe mixture was warmed
2. temperatureat reflux
3. waitAfter 24 hours
4. waitAfter 18 hours
5. temperaturethe mixture was cooled
6. filtrationfiltered
7. concentrationconcentrated in vacuo
8. customto afford a brown oil
9. customThe residue was purified by column chromatography over silica gel eluting with 0-100% methylene chloride in hexanes
10. customthe product-rich fractions were collected