In the title mol-ecule, C(18)H(23)NO(3), the hydro-per-oxy-butyl substituent is nearly fully extended, with the four torsion angles in the range 170.23 (10)-178.71 (9)°. The O-O distance in the hydro-peroxide group is 1.4690 (13) Å. This group acts as an inter-molecular hydrogen-bond donor to a quinoline N atom. This results in dimeric units about the respective inversion centers, with graph-set notation R(2) (2)(18).