p-Toluenesulfonic acid → 5-[2-(4-Chloro-phenyl)-ethylamino]-1-methyl-5,6,7,8-tetrahydro-1H-quinolin-2-one

A mixture of 2-(4-chlorophenyl)ethylamine (5.8 g), 5,6,7,8-tetrahydro-1-methyl-5-oxo-2(1H)-quinolinone (5.5 g), and a catalytic amount of para-toluenesulfonic acid was heated in refluxing toluene (90 ml), with azeotropic removal of water, for 40 hrs. The solution was cooled and concentrated in vacuo. Sodium borohydride (1.1 g) was added to a solution of the residue in ethyl alcohol (90 ml), and the mixture was stirred at room temperature for 2 hrs. The mixture was concentrated in vacuo, the residue was quenched with water, and the mixture was extracted with dichloromethane. The combined organic layers were washed with brine, dried over anhydrous magnesium sulfate, filtered, and the filtrate was concentrated. Recrystallization of the residue from ethyl acetate/hexanes provided 6.55 g (67%) of product, mp 110°-112° C.

1. customwith azeotropic removal of water
2. temperatureThe solution was cooled
3. concentrationconcentrated in vacuo
4. additionSodium borohydride (1.1 g) was added to a solution of the residue in ethyl alcohol (90 ml)
5. concentrationThe mixture was concentrated in vacuo
6. customthe residue was quenched with water
7. extractionthe mixture was extracted with dichloromethane
8. washThe combined organic layers were washed with brine
9. dry with materialdried over anhydrous magnesium sulfate
10. filtrationfiltered
11. concentrationthe filtrate was concentrated
12. customRecrystallization of the residue from ethyl acetate/hexanes

ORD record

ord-33167b47f803456783d191c7e8cb35d8

Source dataset

uspto-grants-1992_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05110815