Synthesis and characterization of alt-bipyridinylene-phenylene copolymers containing ruthenium(II) complexes

Abstract

Poly{bis(4,4′-tert-butyl-2,2′-bipyridine)-(2, 2′-bipyridine-5,5′-diyl-[1,4-phenylene] )-ruthenium(II) bishexafluorophosphate} (3a), poly{bis(4,4′-tert-butyl-2,2′- bipyridine)-(2,2′-bipyridine-4,4′-diyl-[1,4-phenylene]) -ruthenium(II)bishexafluorophosphate} (3b), and poly{bis(2,2′-bipyridine)- (2,2′-bipyridine-5,5′-diyl-[1,4-phenylene])ruthenium(II) bishexanuorophosphate} (3c) were synthesized by the Suzuki coupling reaction. The alternating structure of the copolymers was confirmed by 1H and 13C NMR and elemental analysis. The polymers showed, by ultraviolet-visible, the π-π* absorption of the polymer backbone (320-380 nm) and at a lower energy attributed to the d-π* metal-to-ligand charge-transfer absorption (450 nm for linear 3a and 480 nm for angular 3b). The polymers were characterized by a monomodal molecular weight distribution. The degree of polymerization was approximately 8 for polymer 3b and 28 for polymer 3d. © 2004 Wiley Periodicals, Inc.