Terpyridine- and Bipyridine-Based Ruthenium Complexes as Catalysts for the Belousov-Zhabotinsky Reaction

Department of Chemistry, Brandeis University, Waltham, Massachusetts 02454-9110, USA.
The Journal of Physical Chemistry A (Impact Factor: 2.78). 02/2011; 115(11):2208-15. DOI: 10.1021/jp111724t
Source: PubMed

ABSTRACT We report the successful use of Ru(II)(terpy)(2) (1, terpy = 2,2':6',2''-terpyridine) as a catalyst in the Belousov-Zhabotinsky (BZ) oscillating chemical reaction. We also examine several additional Ru(II) complexes, Ru(II)(bipy)(2)(L')(2) (2, L' = 4-pyridinecarboxylic acid; bipy = 2,2'-bipyridine) and Ru(II)(bipy)(2)(L'') (3, L'' = 4,4'-dicarboxy-2,2'-bipy; 4, L'' = N-allyl-4'-methyl-[2,2'-bipy]-4-carboxamide; 5, L'' = bipy), for catalyzing the BZ reaction. While 2 is unable to trigger BZ oscillations, probably because of the rapid loss of L' in a BZ solution, the other bipyridine-based Ru(II)-complexes can catalyze the BZ reaction, although their catalytic activity is adversely affected by slow ligand substitution in a BZ solution. Nevertheless, the successfully tested Ru(II)(terpy)(2) and Ru(II)(bipy)(2)(L'') catalysts may provide useful building blocks for complex functional macromolecules.

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