反应详情

A solution of 2-(n-undecyl)indole-6-carboxylic acid (11.9 g) in ethanol (50 ml) containing a solution of hydrogen chloride gas in ethanol (75 ml, of strength 39% w/v) was refluxed for 4.5 hours. The solution was cooled and a solid was collected which was dissolved in diethyl ether, and the ethereal solution was washed with water (2×100 ml) and dried over magnesium sulphate. The solvent was removed in vacuo to give a residue which was recrystallised from methanol to give ethyl 2-(n-undecyl)indole-6-carboxylate (6.2 g), in the form of very pale yellow needles, m.p. 84°-86° C.

1. temperaturewas refluxed for 4.5 hours
2. temperatureThe solution was cooled
3. customa solid was collected which
4. dissolutionwas dissolved in diethyl ether
5. washthe ethereal solution was washed with water (2×100 ml)
6. dry with materialdried over magnesium sulphate
7. customThe solvent was removed in vacuo
8. customto give a residue which
9. customwas recrystallised from methanol