5,7-Dibromo-8-methoxyquinoline

Abstract

In the title compound, C 10 H 7 Br 2 NO, the methoxy C atom deviates from the quinoline ring system (r.m.s deviation = 0.003 Å ) by 1.204 (4) Å . In the crystal, C-HÁ Á ÁO hydrogen bonds link the molecules into infinite chains along the baxis direction. Aromatic -stacking interactions [centroid-to-centroid distance = 3.7659 (19) Å ] are also observed. Structure descriptionThe treatment of several dihalogenated quinoline derivatives with NaOMe in basic solutions afforded mono methoxide analogues (Politanskaya et al., 2005). Our own work has studied the bromination reactions of substituted quinolines (Ö kten & Ç akmak, 2015; Ö kten et al., 2015). The present study presents the crystal structure of 5,7-dibromo-8-hydroxyquinoline.In the title compound ( Fig. 1), the Br-C bond lengths are 1.889 (3) and 1.901 (3) Å , and the Br-C-C bond angles vary from 117.6 (2) to 120.2 (2). The relatively wide range of Br-C-C angles may be due to the alternation of the bond-lengths in the bromine-substituted six-membered ring, which vary from 1.357 (4) to 1.425 (4) Å .The packing of the title compound viewed down the b axis is shown in Fig. 2. The crystal structure features C-HÁ Á ÁO hydrogen bonds, which lead to the formation of chains along the b-axis direction (Fig. 3 and Table 1). Furthermore, aromatic -stacking interactions [Cg1Á Á ÁCg2(x, 1 + y, z) = 3.7659 (19) Å ; Cg1 and Cg2 are the centroids of the N1/C1-C5 pyridine and C4-C9 benzene rings, respectively] in the [010] direction are also observed. Keywords: crystal structure; quinoline ring system; hydrogen bonds; -stacking interactions. CCDC reference: 1546956Structural data: full structural data are available from iucrdata.iucr.org data reports Synthesis and crystallization 5,7-Dibromoquinolin-8-ol (1.0 g, 3.3 mmol) was added to a solution of NaOH (132 mg, 3.3 mmol) in distilled water (100 ml). Me 2 SO 4 (416 mg, 3.3 mmol) was added dropwise to the mixture at 263 K for 1 h while being stirred. The mixture was heated to 343-353 K for 1 h. After completion of the reaction (the colour of the mixture changed, 2 h), the solid was dissolved in CHCl 3 (50 ml). The organic layer was successively washed with 10% Na 2 CO 3 (2 Â 15 ml) and 10% NaOH (2 Â 15 ml), dried over Na 2 SO 4 , and the solvent was removed under vacuum. The crude material (2.12 g) was passed through a short alumina column and eluted with EtOAchexane (1:6, 150 ml) to obtain the title compound (1 g, 95%) as colourless needles, m.p. 372-375 K.

Quinoline‐based promising anticancer and antibacterial agents, and some metabolic enzyme inhibitors

“…[14,39] Furthermore, the synthesis of 5,7-dibromo-8-hydroxyquinoline (17) and 5,7-dibromo-8-methoxyquinoline (19) via bromination of 8hydroxyquinoline (15) and 8-methoxyquinoline (16), respectively, was reported in our recent works. [40,55] The isolated compounds, 2-10, 12-14, and 17-19, were fully characterized by melting point, HRMS analysis, infrared, 1 H, 13 C, HMBC (heteronuclear multiple bond correlation), and HETCOR spectroscopy in these papers. [6,29,30,39,40,43] All tested compounds were purified by column chromatography.…”