反应详情

13ad) A solution of 20 g of ethyl 2-(4-bromo-2-chloro-benzoyl)-3-dimethylaminoacrylate (Example 13ac)) in 200 ml of dimethyl sulphoxide is treated with 5.5 g of cyclohexylamine and stirred at room temperature under argon for 45 min. Immediately after the addition the solution begins to decolourize and a colourless, gel-like substance separates. 6.84 g of potassium tert-butylate are added in one portion to this suspension. The resulting suspension is stirred at room temperature for 10 min. and subsequently heated to 50° for 1.5 hrs. The reaction mixture is left to cool to room temperature, poured into 600 ml of ice-water and stirred for a further 30 min. The suspension is suction filtered, the filter residue is washed three times with 100 ml of water each time and three times with 100 ml of hexane each time and dried. Recrystallization of the crude product from ethyl acetate/hexane yields 14.8 g (90%) of ethyl 7-bromo-1-cyclohexyl-4-oxo-1,4-dihydro-quinoline-3-carboxylate as a colourless solid. M.p. 129°-133°.

1. additionImmediately after the addition the solution
2. stirringThe resulting suspension is stirred at room temperature for 10 min.
3. temperaturesubsequently heated to 50° for 1.5 hrs
4. waitThe reaction mixture is left
5. temperatureto cool to room temperature
6. stirringstirred for a further 30 min
7. filtrationsuction filtered
8. washthe filter residue is washed three times with 100 ml of water each time and three times with 100 ml of hexane each time
9. customdried
10. customRecrystallization of the crude product from ethyl acetate/hexane