Toward the Development of Molecular Wires: Ruthenium(II) Terpyridine Complexes Containing Polyferrocenyl as a Spacer
摘要:
The preparations of multinuclear supramolecules assembled from 1,1'-bis(terpyridyl)ferrocene, 1,1'-bis(terpyridyl)biferrocene, and 1,1'-bis(terpyridyl)triferrocene (tpy-(fc)(n)-tpy, n = 1-3) redox-active moieties with Ru2+ metal centers are described. The electrochemical measurements of the Ru2+ complexes of tpy-(fc)(n)-tpy (1a (n = 1); 1b (n = 2); 1c (n = 3)) are dominated by the Ru2+/Ru3+ redox couple (E-1/2 from 1.35 to 1.38 V), Fe2+/Fe3+ redox couples (E-1/2 from similar to 0.4 to similar to 1.0 V), and tpy/tpy-/tpy(2-) redox couples (E-1/2 from -1.3 to -1.5 V). The appreciable variations detected in the Fe2+/Fe3+ oxidation potentials indicate that there is an interaction between the spacer and the Ru2+ metal centers. Coordination of Ru2+ metal centers to tPY-(fc)(n)-tpy results in a red-shifted and more intense (1)[(d(pi)(Fe))(6)] -> (1)[(d(pi)(Fe))(5)-(pi*(Ru)(tpy))(1)] transition in the visible region. The observed red-shifted absorption from 526 nm in the monomeric [Ru(fctpy)(2)](2+) complex to similar to 560 nm in 1b and 1c reveals that there is a qualitative electronic coupling within the ferrocenyl array. The Fe-Fe interactions result in a red characteristic of the (1)[(d(pi)(Fe))(6)] -> (1)[(d(pi)(Fe))(5)(pi*(Ru)(tpy))(1)] MMLCT transition.
Toward the Development of Molecular Wires: Ruthenium(II) Terpyridine Complexes Containing Polyferrocenyl as a Spacer
摘要:
The preparations of multinuclear supramolecules assembled from 1,1'-bis(terpyridyl)ferrocene, 1,1'-bis(terpyridyl)biferrocene, and 1,1'-bis(terpyridyl)triferrocene (tpy-(fc)(n)-tpy, n = 1-3) redox-active moieties with Ru2+ metal centers are described. The electrochemical measurements of the Ru2+ complexes of tpy-(fc)(n)-tpy (1a (n = 1); 1b (n = 2); 1c (n = 3)) are dominated by the Ru2+/Ru3+ redox couple (E-1/2 from 1.35 to 1.38 V), Fe2+/Fe3+ redox couples (E-1/2 from similar to 0.4 to similar to 1.0 V), and tpy/tpy-/tpy(2-) redox couples (E-1/2 from -1.3 to -1.5 V). The appreciable variations detected in the Fe2+/Fe3+ oxidation potentials indicate that there is an interaction between the spacer and the Ru2+ metal centers. Coordination of Ru2+ metal centers to tPY-(fc)(n)-tpy results in a red-shifted and more intense (1)[(d(pi)(Fe))(6)] -> (1)[(d(pi)(Fe))(5)-(pi*(Ru)(tpy))(1)] transition in the visible region. The observed red-shifted absorption from 526 nm in the monomeric [Ru(fctpy)(2)](2+) complex to similar to 560 nm in 1b and 1c reveals that there is a qualitative electronic coupling within the ferrocenyl array. The Fe-Fe interactions result in a red characteristic of the (1)[(d(pi)(Fe))(6)] -> (1)[(d(pi)(Fe))(5)(pi*(Ru)(tpy))(1)] MMLCT transition.