Reactivity of the europium hexafluoroacetylacetonate (hfac) complex, Eu(hfac)3(diglyme), and related analogs with potassium: formation of the fluoride hfac “ate” complexes, [LnF(hfac)3K(diglyme)]2

Evans, William J.; Giarikos, Dimitrios G.; Johnston, Malcolm C.; Greci, Michael A.

doi:10.1039/b104095m

Cited by 71 publications

(34 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The preparation of the boronic ester 2 and boronic acids 3 – 5 are collected in Appendix 2 (Supporting Information). The hexafluoroacetylacetonate salts [Ln(hfac) 3 (diglyme)] were prepared from the corresponding oxide (Appendix 2) . DMF and dichloromethane were distilled over calcium hydride.…”

Section: Methodsmentioning

confidence: 99%

Looking for the Origin of Allosteric Cooperativity in Metallopolymers

Babel

Hoang

Guénée

et al. 2016

Chemistry A European J

View full text Add to dashboard Cite

The basic concept of allosteric cooperativity used in biology, chemistry and physics states that any change in the intermolecular host-guest interactions operating in multisite receptors can be assigned to intersite interactions. Using lanthanide metals as guests and linear multi-tridentate linear oligomers of variable lengths and geometries as hosts, this work shows that the quantitative modeling of metal loadings requires the consideration of a novel phenomenon originating from solvation processes. It stepwise modulates the intrinsic affinity of each isolated site in multisite receptors, and this without resorting to allosteric cooperativity. An easy-to-handle additive model predicts a negative power law dependence of the intrinsic affinity on the length of the linear metallopolymer. Applied to lanthanidopolymers, the latter common analysis overestimates cooperativity factors by more than two orders of magnitude.

show abstract

Section: Methodsmentioning

confidence: 99%

Looking for the Origin of Allosteric Cooperativity in Metallopolymers

Babel

Hoang

Guénée

et al. 2016

Chemistry A European J

View full text Add to dashboard Cite

show abstract

“…[17,18] ) Such complexes are poised for CÀF activation, since the very strong CÀF bonds [19,20] are weakened by coordination. [16] Indeed it has been shown that S,F-chelated [SmA C H T U N G T R E N N U N G (SC 6 F 5 ) 3 ] yields SmF 3 on heating [11] and C,F-chelated [Ce(C 5 H 2 -tBu 3 -1,2,4) 2 C 6 F 5 ] decomposes into the corresponding fluoride and tetrafluorobenzyne.…”

Section: Introductionmentioning

confidence: 99%

Intramolecular Metal–Fluorocarbon Coordination, CF Bond Activation and Lanthanoid–Fluoride Clusters with Tethered Polyfluorophenylamide Ligands

Deacon

Forsyth

Junk

et al. 2009

Chemistry A European J

View full text Add to dashboard Cite

Activating C--F bonds: Strong metal-fluorocarbon coordination in complexes of electropositive metals (e.g., Na, K, Yb) with chelating polyfluorophenyl-substituted amide ligands is a precursor to C--F bond activation and fluoride abstraction when M=Yb(II), giving heteroleptic Yb(III) fluoride clusters (see scheme).Metalation of either N,N-diethyl- or N,N-dimethyl-N'-2,3,5,6-tetrafluorophenylethane-1,2-diamines (HL 1 a, 1 b respectively) with [M{N(SiMe(3))(2)}] (M=Na, K) or [Yb{N(SiMe(3))(2)}(2)(thf)(2)] yielded the metal-amido compounds [Na(L)] (2 a), [K(L)] (3 a) and [Yb(L)(2)(thf)(2)] (4 a, 4 b). The Yb complexes were also synthesised by redox transmetalation/ligand exchange from Yb, Hg(C(6)F(5))(2) and HL in THF or 4 a from a reaction of 3 a with YbI(2) in THF. In the presence of N,N,N',N'- tetramethyl-1,2-ethanediamine (TMEDA) the complexes 2 a and 3 a yielded [Na(L)(2)Na(tmeda)] (5 a) and [K(2)(L)(2)(tmeda)(2)] (6 a), respectively, as crystalline compounds, whilst crystallisation of 4 a from DME gave [Yb(L)(2)(dme)] (7 a). Their structures have chelating metal-amide and NR(2) donors and additional intramolecular M-F-C connectivity with relatively short bond lengths (Na--F 2.65-3.00 A; K--F 2.70-3.00 A; Yb--F 2.56 A). The Yb complexes undergo C--F activation in solution forming [Yb(4)(L)(6)F(6)] (8 a, 8 b). The connectivity of [Yb(4)(L)(6)F(6)], as shown by the X-ray structures, comprised a circular Yb(4)(mu-F)(4) periphery with two opposing Yb centres having either one L ligand and a Yb(2)(mu-F)(2) bridge or two L ligands. Each polyfluorophenylamide exhibits additional intramolecular Yb-F-C coordination from one of the ortho-F atoms resulting in seven or eight coordinate Yb centres. An attempt to synthesise 4 a by redox transmetalation/ligand exchange using Hg(C[triple chemical bond]CPh)(2) as the mercury reagent gave [Yb(4)(O)(2)(L)(4)(C[triple chemical bond]CPh)(4)(thf)(2)]THF (9 aTHF), most likely as a result of oxidation of the initially formed product.

show abstract

“…The hydrogen atoms were included in the final refinement model in calculated positions with isotropic thermal parameters [22,23]. The disorder of F atoms was manifested by several thermal vibration parameters, and therefore some restraints were still used [24,25].…”

Section: X-ray Structure Analysismentioning

confidence: 99%