Crystal structure of 1,3-bis(6-methoxyquinolin-2-yl)benzene, C26H20N2O2

Abstract

Source of materialThe title compound, C 26 H 20 N 2 O 2 , was prepared by the reaction of p-anisidine with terephthaldialdehyde and N-vinyl-2-pyrrolidone at room temperature. A mixture of p-anisidine (3 mmol) and isophthalaldehyde (1.5 mmol) in anhydrous CH 3 CN (5 mL) under N 2 , was stirred at room temperature for 1 hour. BiCl 3 (20 mol %) was added. Over a period of 20 min, a solution the N-vinyl-2-pirrolidone (3.1 mmol) in CH 3 CN (5 mL) was added dropwise. The resulting mixture was stirred for 8-10 h. After completion of the reaction as indicated by TLC, the reaction mixture was diluted with (15 mL) and extracted with ethyl acetate (3´10 mL). The organic layer was separated, and dried with Na 2 SO 4 . The organic solvent was removed in vacuo and the resulting product was purified by column chromatography (silica gel, petroleum ether/EtOAc) to afford pure substances, tetrahydroquinoline and 1,3-bis(6-methoxyquinolin-2-yl)benzene. Analysis: Solid crystalline m.p. 224-227°C. 13 C NMR (400 MHz, CDCl 3 ) d: 157.4 (2), 154.6 (2), 144.1 (2), 140 (2), 135.2 (2), 130.9 (2), 128.3 (1), 127.9 (2), 127.6 (2), 126 (1), 122 (2), 119.1 (2), 104.7 (2), 55.2 (2). Experimental detailsH atoms were located in the difference Fourier map, but refined with fixed individual displacement parameters, using a riding model with C-H distances of 0.95 Å (for CH), 0.98 Å (for CH 3 ), with U iso (H) values of 1.2U eq (C) (for CH) and 1.5U eq (C) (for CH 3 ). DiscussionHeterocyclic compounds, especially those with nitrogen, are the most important class of compounds in the pharmaceutical and agrochemical industries [1]. Quinoline systems in particular constitute a privileged substructure and are found in numerous biologically active natural products and pharmacologically relevant therapeutic agents [2]. These organic molecules have attracted attention of both synthetic and medicinal chemists. (12) and 2.96(12)°. In the molecular structure, the most noticeable deviation from planarity are expressed by the torsion angles of the methoxy groups with respect to adjacent quinoline system [C8-O2-C26-C25 = 5.3(3) and C7-