Alkali-metal binding properties of simple ferrocenyl- and ruthenocenyl-substituted aza-crown ethers

Two electroactive ferrocenyl chalcones as original optical chemosensors for Ca2+ and Ba2+ cations in CH3CN

“…NMR investigations show that weak interaction probably takes place with the crown ring inducing a 0.38 ppm downfield-shift and a broadening of the 7 Li signal when compared to that of Li(CF 3 SO 3 ) salt (d = À2.48 ppm). This crown interaction is in agreement with data reported for the [(C 5 H 5 )Fe(C 5 H 4 CO-aza-15-crown-5)] compound but not with the [Fe(C 5 H 4 CO-aza-15-crown-5) 2 ] compound where a CO interaction is preferred [28]. The Li + cation is small and different coordination modes involving all, or a part of the nitrogen or/and [28], 2 does not electrochemically detect Li + .…”

“…This crown interaction is in agreement with data reported for the [(C 5 H 5 )Fe(C 5 H 4 CO-aza-15-crown-5)] compound but not with the [Fe(C 5 H 4 CO-aza-15-crown-5) 2 ] compound where a CO interaction is preferred [28]. The Li + cation is small and different coordination modes involving all, or a part of the nitrogen or/and [28], 2 does not electrochemically detect Li + . For this reason we have not developed further the optical analysis, as we were first interested by multidetection of the same cation by different techniques.…”

Multi-signaling detection of Hg2+ and Cu2+ by a ferrocene–pyrazole dyad associated with molecular-scale arithmetic

“…The peak corresponding to uncomplexed species completely disappeared upon one equivalent addition. The electrochemical responses obtained for R with Hg 2+ ion was consistent with such cation-π interaction with ferrocene moiety reported by Grossel et al [28] The fluorescence spectrum of R in CH 3 CN (5 × 10 − 5 M) were obtained and the emission spectrum is characterized by the emission maximum observed at 381 nm upon excitation at 315 nm. The change in the fluorescence properties of R caused by different metal ions were measured in CH 3 CN.…”

Intramolecular Electrostatics: Coulomb's Law at Sub‐Nanometers

“…These basic voltammetric features of the six ligands are in agreement with previous reports of similar compounds. [11][12][13] In the presence of HPF 6 , LiClO 4 , NaClO 4 , KPF 6 , Mg(ClO 4 ) 2 , or Ba(ClO 4 ) 2 , the voltammetric measurements revealed a positive shift (DE 1/2 = E 1/2,complex ÀE 1/2,ligand ) of the mean potential [E 1/2 = (E pa + E pc )/2] for every ligand; this potential shift was accompanied by variations of other voltammetric features. Typical examples of the most common changes are presented in Figure 1 for the CVs and SWVs of 6a in the absence and presence of LiClO 4 ; the observed changes can be related with the free ligand and the ligand-cation complex, as well as with the complexation stoichiometry, which can be determined by titration.…”

“…These molecules were synthesized using the procedures reported in the literature. [11,12] The new host molecules have, between the centers of the redox and the macrocycle groups, an alkyl spacer with a length of a few angstroms or sub-nanometers; therefore, these molecules are ideal models for studying electrostatic interactions at the sub-nanometer scale. Furthermore, the flexibility of the macrocycle is reduced by the presence of the rigid 1,2-oxy-benzene moiety.…”