TY - JOUR
T1 - Ruthenium(II)-cored polythiophene dendrimers
AU - Deng, Suxiang
AU - Krueger, Greg
AU - Taranekar, Prasad
AU - Sriwichai, Saengrawee
AU - Zong, Ruifa
AU - Thummel, Randolph P.
AU - Advincula, Rigoberto C.
PY - 2011/7/26
Y1 - 2011/7/26
N2 - We report the synthesis and characterization of ruthenium(II)-cored polythiophene dendrimers. Four new redox-active ruthenium(II) pyridine oligothiophene dendritic complexes that fluoresce in the near-infrared region have been synthesized, and their absorption spectra, fluorescence properties, and redox behavior have been investigated. The dendritic ligands phen3T and phen7T containing 1,10-phenanthroline as chelating sites and two oligothiophene dendrons (3T6COMe and 7T6COMe) have been synthesized and employed. The metal-polythiophene dendrimers investigated here are [Ru(bpy) 2(phen3T)]2+, [Ru(bpy)2(phen7T)]2+, [Ru(phen3T)3]2+, and [Ru(phen7T)3] 2+. Upon addition of acid, the charge transfer absorption bands of free dendritic ligands are significantly red-shifted and the fluorescence is greatly quenched. The Ru(II) polythiophene dendrimers exhibit very strong metal-to-ligand charge transfer (MLCT) absorption and enhanced absorption in the UV region and can be regarded as better light-harvesting species. The MLCT emission is extraordinarily red-shifted (∼165 nm) because of their planar excited states. The core of the dendrimers shows an electrochemical behavior typical of encapsulated metal electroactive units.
AB - We report the synthesis and characterization of ruthenium(II)-cored polythiophene dendrimers. Four new redox-active ruthenium(II) pyridine oligothiophene dendritic complexes that fluoresce in the near-infrared region have been synthesized, and their absorption spectra, fluorescence properties, and redox behavior have been investigated. The dendritic ligands phen3T and phen7T containing 1,10-phenanthroline as chelating sites and two oligothiophene dendrons (3T6COMe and 7T6COMe) have been synthesized and employed. The metal-polythiophene dendrimers investigated here are [Ru(bpy) 2(phen3T)]2+, [Ru(bpy)2(phen7T)]2+, [Ru(phen3T)3]2+, and [Ru(phen7T)3] 2+. Upon addition of acid, the charge transfer absorption bands of free dendritic ligands are significantly red-shifted and the fluorescence is greatly quenched. The Ru(II) polythiophene dendrimers exhibit very strong metal-to-ligand charge transfer (MLCT) absorption and enhanced absorption in the UV region and can be regarded as better light-harvesting species. The MLCT emission is extraordinarily red-shifted (∼165 nm) because of their planar excited states. The core of the dendrimers shows an electrochemical behavior typical of encapsulated metal electroactive units.
KW - dendrimers
KW - metal-to-ligand charge transfer
KW - oligothiophene
KW - ruthenium
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U2 - 10.1021/cm200228p
DO - 10.1021/cm200228p
M3 - Article
AN - SCOPUS:79960503128
SN - 0897-4756
VL - 23
SP - 3302
EP - 3311
JO - Chemistry of Materials
JF - Chemistry of Materials
IS - 14
ER -