A new bipyridine-functionalized dithioester was synthesized and further used as a RAFT agent in RAFT polymerization of styrene and N-isopropylacrylamide. Kinetics analysis indicates that it is an efficient chain transfer agent for RAFT polymerization of the two monomers which produce polystyrene and poly(N-isopropylacrylamide) polymers with predetermined molecular weights and low polydispersities in addition to the end functionality of bipyridine. The bipyridine end-functionalized polymers were further used as macroligands for the preparation of star-shaped metallo-polymers. Hydrophobic polystyrene macroligand combined with hydrophiphilic poly(N-isopropylacrylamide) was complexed. with ruthenium ions to produce amphiphilic ruthenium-cored star-shaped metallopolymers. The structures of these synthesized metallopolymers were further elucidated by UV-vis, fluorescence, size exclusion chromatography (SEC), and differential scanning calorimetry (DSC) as well as NMR techniques. (c) 2007 Wiley Periodicals, Inc.