3d and 4d coordination complexes and coordination polymers involving electroactive tetrathiafulvalene containing ligands

International audienceThe "through bond" approach has been recently developed to increase the interaction between the mobile π and localized d electrons in multifunctional molecular materials involving tetrathiafulvalene-based ligands. This article reviews the 3d and 4d coordination complexes and polymers elaborated from a library of tetrathiafulvalene derivatives containing ligands obtained recently in our group. The different synthetic ways of the complexes are highlighted as well as their chemical and physical properties

Synthesis, Characterization, and Preliminary Study of [Co(2- aminopyridine)2(NCS)2] or bis(2-aminopyridine)dithiocyanato cobalt(II) as An Antibacterial

This study aims to synthesize complex compounds from the Co(II) ion with mixed ligands of 2-aminopyridine and thiocyanate ions. The complexes obtained have Co(II) : 2-aminopyridine: thiocyanate ratio of 1:2:2 based on preliminary analysis by SEM-EDX, DHL, and FTIR. The complex in the form of a blue needle crystal is stable at room temperature and melts at 169 °C. Characterization shows that the complex formed is neutral. The antibacterial activity test was carried out using the diffusion method and show that the resulting complex compounds could inhibit the growth of S. typhi and S. aureus bacteria better than 2-aminopyridine

[Cu(tn)]3[Cr(CN)6]2·3H2O: a unique two-dimensional Cu–Cr cyano-bridged ferromagnet (tn = 1,3-diaminopropane)

Reaction of the two-coordinate ‘assembling complex-ligand’ [Cu(tn)]2+ with the building block [Cr(CN)6]32 leads to a unique two-dimensional Cu–Cr cyano-bridged ferromagnet with unusual m3- and m4-bridging [Cu(tn)]2+ units.Gomez Garcia, Carlos Jose, [email protected]

Synthesis, Structure, Magnetic and Antibacterial Properties of polymeric [M(Quin)2(N(CN)2)2]∞ (M = Mn(II), Co(II); Quin = quinoline)

Two complexes of [Mn(Quin)2(N(CN)2)2]∞ (1) and [Co(Quin)2(N(CN)2)2]∞ (2) were synthesized and characterized. The as-synthesized complexes crystallized in a triclinic lattice with a space group of P-1. The unit cell parameter of 1 was a = 7.5207(14) Å, b = 7.7729(16) Å, c = 9.5968(15) Å, α = 96.388(6) o, β = 112.617(5) o, γ = 102.751(6) o, while for complex 2 it was a = 7.3942(10) Å, b = 7.7960(10) Å, c = 9.4907(13) Å, α = 96.631(4) o, β = 112.742(4) o, γ = 102.458(4) o. The magnetic properties and antimicrobial properties of both polymeric complexes were examined by magnetic susceptibility and diffusion techniques, respectively. Complexes 1 and 2 both showed antiferromagnetic properties and had a higher inhibitory effect on the growth of Staphylococcus aureus than Salmonella typhi

A new approach towards ferromagnetic conducting materials based on TTF-containing polynuclear complexes

International audienceFive complexes containing binuclear cation [Cu2(LH)2]2+ (LH2 = 1 : 2 Schiff base of 1,3-diaminobenzene and butanedione monoxime) were prepared and characterized. Metathesis of one perchlorate anion in [Cu2(LH)2(H2O)2](ClO4)2 (1) by anionic TTF-carboxylate (TTF-CO2−) leads to the complex [Cu2(LH)2(CH3OH)2](TTF-CO2)(ClO4)*H2O (2). Reactions of 1 with substituted pyridines bipy, dpe and TTF-CH = CH-py result in formation of the complexes {[Cu2(LH)2(bipy)](ClO4)2}n*2nH2O (3), [Cu2(LH)2(dpe)2](ClO4)2*2CH3OH (4) and [Cu2(LH)2(TTF-CH = CH-py)(H2O)](ClO4)2*1.5H2O (5), where bipy = 4,4′-bipyridine, dpe = trans-(4-pyridyl)-1,2-ethylene and TTF-CH = CH-py = 1-(2-tetrathiafulvalenyl)-2-(4-pyridyl)ethylene. Whereas complex 2 is built from discrete ionic particles (with rather long Cu-S contacts), compounds 1 and 3 contain 1D polymeric chains, in which structural units are bonded through Cu-O bonds or through bridging bipy molecule, respectively. Dinuclear complexes 4 and 5 are linked though π-stacking of dpe or TTF-CH = CH-py, respectively. All complexes are characterized by dominating ferromagnetic behavior with J values in the range from +9.92(8) cm−1 to +13.4(2) cm−1 for Hamiltonian H = -JS1S2. Magnetic properties of the compounds, containing stacks of aromatic molecules in crystal structures (4 and 5), correspond to ferromagnetic intradimer and antiferromagnetic intermolecular interactions (zJ′ = −0.158(3) and −0.290(2) cm−1, respectively). It was found that TTF-CH = CH-py ligand in [Cu2(LH)2(TTF-CH = CH-py)(H2O)]2+ could be electrochemically oxidized to cation-radical form in the solution

Heptanuclear hydroxo-bridged copper cluster of the dicubane-like type: structural and magnetic characterisations of [Cu7(OH)6Cl2(pn)6(H2O)2](C(CN)3)4Cl2 (pn = 1,3-diaminopropane)

A new polynuclear copper(II) complex [Cu7(OH)6Cl2- (pn)6(H2O)2](C(CN)3)4Cl2 with hydroxo-bridging ligands has been prepared; the centrosymmetric cluster cation can be described as two Cu4O3Cl distorted cubane units sharing one copper cation.Clemente Juan, Juan Modesto, [email protected] ; Gomez Garcia, Carlos Jose, [email protected] ; Coronado Miralles, Eugenio, [email protected]

Synthesis, Structure, Magnetic and Antibacterial Properties of polymeric [M(Quin)2(N(CN)2)2]∞ (M = Mn(II), Co(II); Quin = quinoline)

Two complexes of [Mn(Quin)2(N(CN)2)2]∞ (1) and [Co(Quin)2(N(CN)2)2]∞ (2) were synthesized and characterized. The as-synthesized complexes crystallized in a triclinic lattice with a space group of P-1. The unit cell parameter of 1 was a = 7.5207(14) Å, b = 7.7729(16) Å, c = 9.5968(15) Å, α = 96.388(6) o, β = 112.617(5) o, γ = 102.751(6) o, while for complex 2 it was a = 7.3942(10) Å, b = 7.7960(10) Å, c = 9.4907(13) Å, α = 96.631(4) o, β = 112.742(4) o, γ = 102.458(4) o. The magnetic properties and antimicrobial properties of both polymeric complexes were examined by magnetic susceptibility and diffusion techniques, respectively. Complexes 1 and 2 both showed antiferromagnetic properties and had a higher inhibitory effect on the growth of Staphylococcus aureus than Salmonella typhi

Synthesis, Crystal Structure, Magnetic, and Electron Paramagnetic Resonance Properties of a Spiroconjugated Biradical. Evidence for Spiroconjugation Exchange Pathway

A spiroconjugated nitronyl nitroxide biradical, 6,6‘-(4,4,5,5-tetramethylimidazolidine-3-oxide-1-oxyl)-3,3,3‘,3‘-tetramethyl-1,1‘-spirobisindane (1), has been prepared by functionalization of a 3,3,3‘,3‘-tetramethyl-1,1‘-spirobisindane framework followed by Ullman condensation and subsequent oxidation. The biradical crystallizes in the monoclinic space group C2/c with four molecules in the unit cell of dimensions a = 24.861(10) Å, b = 12.129(3) Å, and c = 12.258(6) Å. X-ray analysis of a blue-plate single crystal has revealed dihedral angles of 28° between the nitronyl nitroxide moiety and aromatic ring with intramolecular through space radical−radical distances of 8.25 and 10.11 Å. In the solid state, the temperature dependence of the molar magnetic susceptibility reveals antiferromagnetic interactions. These interactions are best fit using a pair model, affording the value J = −4.0 cm^(-1) where J is the interaction parameter appearing in the spin Hamiltonian H = −JS_1·S_2. The field dependence of the magnetization measured at 2 K is consistent with a pair model. Frozen matrix EPR spectra of biradical 1 in CH_2Cl_2 at 100 K shows a half field transition at 1700 G. Temperature dependence of the half field transition intensity has been found to be consistent with a ground singlet state and thermally accessible triplet state. The magnetic interaction observed in the solid state is also observed in solution. Thus, room-temperature solution spectra display a nine-line pattern, with hyperfine coupling to four “equivalent” nitrogen atoms and a hyperfine coupling constant a_N = 3.8 G. Temperature dependence of the solution EPR spectra of biradical 1 displays alternating line width effects caused by conformational dynamics in solution. This behavior has been attributed to modulation of exchange and hyperfine interactions most likely caused by rotational motion about the nitronyl nitroxide−phenyl bond. Biradical 1 therefore exists as a ground-state singlet with a thermally accessible triplet at ca. 4 cm^(-1) higher in energy with a conformational dependence of intramolecular exchange in solution. This coupling may present evidence for spiroconjugation as an exchange pathway. Density functional calculations (B3/6-311G(D)) have been performed to investigate this possibility