反应详情

12 g (68 mmol) of 3-formyl-8-hydroxy-2-methyl-imidazo[1,2-a]pyridine, 18 g (136 mmol) of 1,2-indenoxide and 9,6 ml (68 mmol) of triethylamine are stirred in 95 ml methanol/water (4:1) for 14 hours at 40° C. The mixture is evaporated at 50° C. in the rotary evaporator, mixed with 200 ml icewater, rendered alkaline with sodium hydroxide solution (approximately pH 13), and the precipitate is filtered off. The filtrate is shaken out with dichloromethane and the organic phase made up to 250 ml with dichloromethane, combined with the precipitate, dried with magnesium sulfate and purified with active charcoal. 250 ml of toluene is added, dichloromethane is distilled off, the mixture is purified at the boiling point with bleaching earth (e.g. Tonsil®), evaporated to half its volume and allowed to crystallize in the refrigerator. The yield of the titel compound m.p. 200°-202° C. is 17.6 g (84%).

1. customThe mixture is evaporated at 50° C. in the rotary evaporator
2. additionmixed with 200 ml icewater
3. filtrationis filtered off
4. dry with materialdried with magnesium sulfate
5. custompurified with active charcoal
6. addition250 ml of toluene is added
7. distillationdichloromethane is distilled off
8. customthe mixture is purified at the boiling point with bleaching earth (e.g. Tonsil®)
9. customevaporated to half its volume
10. customto crystallize in the refrigerator