反应详情

Cyclohexanone (96 mL, 0.926 mol) was added to a stirred solution of methyl indole-6-carboxylic acid (50.0 g, 0.335 mol) in methanol (920 mL) at 22° C. Methanolic sodium methoxide (416 mL of 25% w/w, 1.82 mol) was added in portions over 10 minutes. The mixture was stirred at reflux for 18 hours, cooled to room temperature, concentrated, diluted with cold water, and acidified with 36% HCl solution. The resulting precipitate was collected by filtration, washed with cold water, and dried over phosphorous pentoxide (0.1 mm) to provide the the title compound as a tan colored solid (80.9 g, 97.5% yield).

1. temperatureat reflux for 18 hours
2. concentrationconcentrated
3. additiondiluted with cold water
4. filtrationThe resulting precipitate was collected by filtration
5. washwashed with cold water
6. dry with materialdried over phosphorous pentoxide (0.1 mm)