Structures and physical properties of 1-methyl-1H-pyrrol-2-yl-2,2’:6’,2’’-terpyridine ligand and its chelating Fe/Co metal complexes

• Main Authors: Ming-Jun Hsu, 徐銘駿
• Other Authors: I-Jui Hsu
• Format: Others
• Language: en_US
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/4rtex4

碩士 === 國立臺北科技大學 === 有機高分子研究所 === 105 === In order to design a multifunctional material with magnetic and fluorescent properties, we modify 2,2’:6’,2’’-terpyridine (terpy) to 1-methyl-1H-pyrrol-2-yl-2,2’:6’,2’’-terpyridine(Mtpy) by adding a substituent at 4’-position. Based on previous studies, the electron-withdrawing or electron-releasing substituent can affect redox and photophysical properties of terpyridine and even its chelating with transition metal. In this work, the ligand of mtpy has intermolecular charge-transfer character (the  orbitals conjugation between pyridine and pyrrole units) so that photoluminescence emission spectroscopy displays a red shift effect in comparison with terpy. In addition, the increasing with solvent polarity will also reduce the quantum yield because of the nonradiation decay results. The luminescence property is quenched when the ligand bonds with iron or cobalt metal, but not for zinc complex. The luminescence measurement on Zn(mtpy)2(ClO4)2 indicates the maximum intensity at 472nm with quantum yield 24.84%. In the study of Fe/Co metal complexes chelating by mtpy, we synthesize the [M(mtpy)2X2] (M=Fe(II)/Co(II), and X=BF4-) first, and then prospectively replace one mtpy by two NCS- ligands to form [M(mtpy)(NCS)2]. Furthermore, linking two [M(mtpy)(NCS)2 ] by 4,4’-bipyridine ligand to form a dinuclear metal complex [M(mtpy)(NCS)2-L-M(mtpy)(NCS)2] (L= 4,4’-bipyridine) is also part of our purpose. We make [M(mtpy)2X2] (M=Fe(II)/Co(II), and X=BF4-), [M(mtpy)(NCS)2] and M=Fe, complexes dissolve acetonitrile solvent to get crystals. Based on the single crystal data results, two mtpy ligands chelating metal and NCS- ligands are not bonding with metal rather than becoming counterions balances charge. The physical properties of these complexes are measured by photo-luminescence spectrum and SQUID.