反应详情

To a solution of 6-methyl-1-(3-oxo-1-pentyl)-(1H)-3,4-dihydroquinolin-2-thione [compound 4 wherein (QW)n=Me, R1=R3=R4=R5=H, R2=Me] (350 mg, 1.40 mmol) in anhydrous toluene (4 ml) is added Me2SO4 (227 ml, 2.40 mmol) under stirring and nitrogen atmosphere. The solution is heated at reflux and after 5 min a red oil begins to separate. After further 15 min, DBU (365 ml, 2.40 mmol) is added dropwise to the refluxing two-phase reaction mixture, causing after a few minutes, a darkening of the mixture. The reflux is maintained for 20 min, then the solution is cooled at room temperature, diluted with dichloromethane (50 ml), washed with water (50 ml) and dried over Na2SO4. After filtration and evaporation of the solvent, the dark residual oil is chromatographed (ethyl acetate:light petroleum ether, 1:1, Rf=0.29) affording pure 8-methyl-2,3,5,6-tetrahydro-4-methyl-(1H)-benzo[c]quinolizin-3-one [compound I wherein (QW)n=Me, R1=R3=R4=R5=H and R2=Me] (152 mg, 50%) as an oil which became a solid on standing (mp 143-145° C.)

1. temperatureThe solution is heated
2. temperatureat reflux and after 5 min a red oil
3. customto separate
4. waitcausing after a few minutes
5. temperatureThe reflux is maintained for 20 min
6. washwashed with water (50 ml)
7. dry with materialdried over Na2SO4
8. filtrationAfter filtration and evaporation of the solvent
9. customthe dark residual oil is chromatographed (ethyl acetate:light petroleum ether, 1:1, Rf=0.29)