Preparation and Photophysical Properties of Amide-Linked, Polypyridylruthenium-Derivatized Polystyrene

Publisher Website
Google Scholar
Abstract
The polymer poly(4{2-[N,N-bis(trimethylsilyl)amino]ethyl}styrene), prepared by anionic polymerization and of low polydispersity (Mw/Mn = 1.10−1.18), has been derivatized by amide linkage to [RuII(bpy)2(4-(CO−)-4‘-CH3-bpy)−]2+ (bpy is 2,2‘-bipyridine; 4-(CO−)-4‘-CH3-bpy is 4-carbonyl-4‘-methyl-2,2‘-bipyridine). Unreacted amine sites were converted into acetamides by treatment with acetic anhydride to give derivatized polymers of general formula [PS-CH2CH2NHCO(RuIInMem)](PF6)2n, where m + n = 11, 18, or 25, PS represents the polystyrene backbone, and RuII and Me represent the attached complex and acetamide, respectively. Spectral and electrochemical properties of the derivatized polymers are similar to those of the model [Ru(bpy)2(4-CONHCH2CH2C6H5-4‘-CH3-bpy)]2+ (4-CONHCH2CH2C6H5-4‘-CH3-bpy is 4‘-methyl-2,2‘-bipyridinyl-4-(2-phenylethylamide)), but emission quantum yields (φem) and time-resolved emission decays are slightly dependent on the level of RuII loading, with nonexponential, irradiation-dependent decays appearing at high loadings. The decays could be fitted satisfactorily to the first derivative of the Williams−Watts distribution function. These results are discussed with reference to possible structural and multichromophoric effects on excited-state decay.

This publication has 45 references indexed in Scilit: