Diisopropylethylamine → 3-[3-[4-(5-Methoxy-4-pyrimidyl)-1-piperazinyl]propyl]-5-nitro-1H-indole

Participants

Reaction Steps

A mixture of 5-nitro-3-(3-bromopropyl)indole (4) (0.57 g, 2.0 mmol), 1-(5-methoxy-4-pyrimidyl)piperazine, (1) (0.47 g, 2.4 retool), KI (0.40 g, 2.4 mmol) and diisopropylethylamine (1.75 mL, 10.0 mmol) in 20 mL of acetonitrile was heated to reflux under Ar for 6 h. The cooled reaction mixture was diluted with ethyl acetate and washed (H2O, brine). The aqueous phase was back-extracted with dichloromethane and the combined organic phase was washed (H2O, brine), dried (Na2SO4) and evaporated. The resulting residue was chromatographed (SiO2 /CH2Cl2 -MeOH, 95:5) to give a solid which was triturated with dichloromethane-hexane to afford the title compound (0.55 g, 70%) as a yellow solid, mp 163°-166° C.: IR (KBr) 3440, 3175, 1578, 1320 cm-1 ; 1H NMR (CDCl3, 200 MHz) δ 8.60 (d, J=2.1 Hz, 1H), 8.47 (br s, 1H), 8.33(s, 1H), 8.11 (dd, J=9.0, 2.2 Hz, 1H), 7.89 (s, 1H), 7.38 (d, J=9.0 Hz, 1H), 7.18 (d, J=2.0 Hz, 1H), 3.86 (s, 3H), 3.8-3.9 (m, 4H), 2.86 (t, J=7.4 Hz, 2H), 2.59 (t, J=4.9 Hz, 4H), 2.50 (t, J=7.5 Hz, 2H), 2.05-1.90 (m, 2H). Anal. Calcd for C20H24N6O3. H2O. 0.1 CH2Cl2 : C, 57.08; H, 6.24; N, 19.87. Found: C, 57.37; H, 5.85; N, 19.53.

Provenance & Evidence