Synthesis, crystal structure and photophysical properties of 2,6-bis (benzol(,2-d:4,5-d′]diimidazole-2′-yl)pyridine

A new tridentate benzimidazole derivative, 2,6-bis (benzo[1,2-d:4,5-d']diimidazole-2'-yl)-pyridine (Bzdiimpy), was prepared from o-phenylenediamine in five steps with improved methods according to the literature in good yield. The crystal structure was determined by X-ray diffraction analysis. It crystallized in monoclinic, space group P2(1)/c, with a=1.170 8(4) nm, b=2.479 6(9) nm, c=1.215 9(4) nm, beta=114.641(7)degrees, Z=1, R=0.035 0, wR(2)=0.089 0. The bzdiimp molecule displayed an almost planar structure and formed a zig-zag chain through weak interactions between imidazole-N and [SnCl6](2-)-Cl. Its electronic absorption and emission spectra were measured and compared with the reported analogue 2,6-bis (benz[1,2-d:4,5-d']Imldazole-2'-yl)-pyridine (Bzp).