Analysis of Lanthanide-Radical Magnetic Interactions in Ce(III) 2,2′-Bipyridyl Complexes
| Autor: | Fabrizio Ortu, Nicholas F. Chilton, David P. Mills, Jingjing Liu, Matthew Burton, Marie-Emmanuelle Boulon, Jonathan M. Fowler, Alasdair Formanuik |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
Lanthanide
010405 organic chemistry Magnetism Reducing agent Inorganic chemistry 010402 general chemistry Coupling (probability) 01 natural sciences 0104 chemical sciences Inorganic Chemistry chemistry.chemical_compound Crystallography chemistry Intramolecular force Benzophenone Physical and Theoretical Chemistry Cyclic voltammetry Tetrahydrofuran |
| Zdroj: | Ortu, F, Liu, J, Burton, M, Fowler, J M, Formanuik, A, Boulon, M-E, Chilton, N & Mills, D 2017, ' Analysis of Lanthanide-Radical Magnetic Interactions in Ce(III) 2,2′-Bipyridyl Complexes ', Inorganic Chemistry, vol. 56, no. 5, pp. 2496–2505 . https://doi.org/10.1021/acs.inorgchem.6b02683 |
| ISSN: | 1520-510X 0020-1669 |
| DOI: | 10.1021/acs.inorgchem.6b02683 |
| Popis: | A series of lanthanide complexes bearing organic radical ligands, [Ln(CpR)2(bipy·–)] [Ln = La, CpR = Cptt (1); Ln = Ce, CpR = Cptt (2); Ln = Ce, CpR = Cp″ (3); Ln = Ce, CpR = Cp‴ (4)] [Cptt = {C5H3tBu2-1,3}−; Cp″ = {C5H3(SiMe3)2-1,3}−; Cp‴ = {C5H2(SiMe3)3-1,2,4}−; bipy = 2,2′-bipyridyl], were prepared by reduction of [Ln(CpR)2(μ-I)]2 or [Ce(Cp‴)2(I) (THF)] with KC8 in the presence of bipy (THF = tetrahydrofuran). Complexes 1–4 were thoroughly characterized by structural, spectroscopic, and computational methods, together with magnetism and cyclic voltammetry, to define an unambiguous Ln(III)/bipy·– radical formulation. These complexes can act as selective reducing agents; for example, the reaction of 3 with benzophenone gives [{Ce(Cp”)2(bipy)}2{κ2-O,O′-OPhC(C6H5)CPh2O}] (7), a rare example of a “head-to-tail” coupling product. We estimate the intramolecular exchange coupling for 2–4 using multiconfigurational and spin Hamiltonian methods and find that the commonly used Lines-type isotropic exchange is not appropriate, even for single 4f e–/organic radical pairs. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|