Type

Database

Creator

Date

Thumbnail

Search results

10 records were found.

A series of ruthenium(II) N-heterocyclic carbene chelate complexes were prepd. by using bidentate chelating alkene-carbene, thioether-carbene, carboxylate-carbene and bis-carbene ligands. Metalation of 1-R-3-X-imidazolium salts (1-3, R = Me, X = allyl, MeSCH2CH2; R = mesityl, X = O2CCH2) by either [RuCpCl(PPh2)2] or [RuCl2(cymene)]2 gave the corresponding n-donor-carbene chelates [CpRu(PPh3)[MeSCH2CH2NCN(Me)CH:CH-κS,κC2]][BF4] (6), [CpRu(PPh3)[η2-CH2:CHCH2NCN(Me)CH:CH-κC2]]Y (5a,b, Y = Cl, BF4), [CpRu(PPh3)[O2CCH2NCN(Ar)CH:CH-κO,κC2]] (7, Ar = mesityl), [(η6-cymene)RuCl[η2-CH2:CHCH2NCN(Me)CH:CH-κC2]][BF4] (8), [(η6-cymene)RuCl[MeSCH2CH2NCN(Me)CH:CH-κS,κC2]][BF4] (9), [(η6-cymene)RuCl[O2CCH2NCN(Ar)CH:CH-κO,κC2]] (10). Reaction of 3,3'-diisopropyl-1,1'-methylenebis(imidazolium) diiodide with [RuCl2(arene)]2 gave [(arene)RuCl[iPrNCN(CH:...
In the title compound, [Co2(C2H3O2)4(C7H6N2)4(H2O)], the half-molecule in the asymmetric unit is completed by a crystallographic twofold rotation axis to give the full molecule. The CoII ions are approximately octahedrally coordinated with a cis-N2O4 coordination sphere. The compound features intramolecular O-HO hydrogen bonds between the non-bridging acetate groups and the bridging water molecule, and intermolecular N-HO hydrogen bonds between the acetates and amine H atoms of the benzimidazoles which determine the molecular packing in the crystal structure.
The BN connection: Crystalline and soft molecular networks can be constructed using dative BN bonds (see picture). The networks are obtained in a one-step, three-component reaction involving a triboronic acid, a catechol, and a bipyridyl linker.
A rational design based on the proton-coupled electron transfer (PCET) concept allows us to structurally characterize for the first time isolable, air- and moisture-stable semiquinone radicals in a zwitterionic neutral form. The presence of an alkoxy and the bulky pyridinio substituents causes only a minor perturbation of either the redox potentials or the spectral UV-vis characteristics of the semiquinone core but significantly stabilizes the new radicals.
The synthesis, crystal structures and magnetic properties of five new manganese compounds are reported. These include a linear trinuclear cluster [Mn(II)(3)(O(2)CCHMe(2))(6)(dpa)(2)]center dot 2MeCN (1) (dpa = 2,2'-dipyridylamine), a tetranuclear cluster [Mn(II)(2)Mn(III)(2)O(2)(O(2)CCMe(3))(6)(bpy)(2)] (3) (bpy = 2,2'-bipyridine), and chain coordination polymers composed of cluster blocks such as Mn(3), Mn(3)O, and Mn(4)O(2) bridged by 2,2'-bipyrimidine (bpm) or hexamethylentetramine (hmta) ligands to give ([Mn(II)(2)Mn(III)(2)O(2)(O(2)CCMe(3))(6)(bpm)]center dot 2EtOH)(n) (2), [Mn(II)(2)Mn(III)(2)O(2)(O(2)CCHMe(2))(6)(bpm)(EtOH)(4)](n) (4), and (([Mn(II)(2)Mn(III)(2)O(2)(O(2)CCMe(3))(6)(hmta)(2)]center dot EtOH)(n) (5). The magnetic analysis of the compounds was achieved using a combination of vector coupling and full-matrix diagonal...
We present a series of eight layered copper(II) malonates, each with a {[HA](2)[Cu(II)(mal)(2)(H(2)O)]}(n) A-B-A layer structure, where A is an ammonium cation and 13 is an anionic copper malonate layer (x = 1 or 2; A = benzylamine, 1; S-(alpha)-methylbenzylamine, 2; 4-methylbenzylamine, 3; 4-carboxybenzylamine, 4; 4-trifluoromethylbenzylamine, 5; 4-trifluoromethoxybenzylamine, 6; phenylethylamine, 7; and 4-fluorophenylethylamine, 8). The ammonium cations used are primary amines based around benzylamine and phenylethylamine and include several different functional groups. The different amines give a large array of interlayer interactions, including van der Wail Is packing, hydrogen bonding, C-H center dot center dot center dot pi, pi-center dot center dot center dot pi, H center dot center dot center dot F, and F center dot center dot ...
A π-extended, redox-active tetradentate tetrathiafulvalene-fused salphen [salphen = N,N′-phenylenebis(salicylideneimine)] compound (L) was prepared via a direct Schiff-base condensation of the corresponding diamine-tetrathiafulvalene (TTF) precursor with salicylaldehyde. Its chelating coordination ability has been demonstrated by the formation of the corresponding transition metal complexes in the presence of M(OAc)2·nH2O (M = Co(II), Ni(II), Cu(II)) and FeCl3·6H2O. Three complexes have been characterized by single-crystal X-ray diffraction analysis showing that the TTF-salphen ligand coordinates to the metal ions in a planar mode through the nitrogen and oxygen atoms in a N2O2 cis-configuration. In the case of Fe(III), a dinuclear oxo-bridged Fe(III) complex is formed. These paramagnetic complexes are promising building blocks for the...
We report here two series of coordination polymer chains: the first being [M(II)(ox)(bnz)(2)](n) (M = Mn 1, Fe 2, Co 3, Ni 4, Cu 5 and Zn 6; ox = oxalate C(2)O(4)(2-); bnz = benzimidazole) and the second [M(II)(ox)(btz)(2)](n) (M = Mn 7, Fe 8, Co 9, Ni 10, Cu 11 and Zn 12; btz = benzotriazole). The first series displays an unusual homometallic [-M(i)-M(ii)-M(ii)-](n) chain topology and the second series is isostructural to [Fe(II)(ox)(btz)(2)](n), originally reported by Jia et al. (Collect. Czech. Chem. Commun., 2002, 67, 1609-1615). These two series allow us to make comparisons between the spin state of each metal and the magnetic coupling interaction within an isostructural series spanning the full range of spin states available in 3d metals and to investigate which models are the best to use in each case. Compound 8 is a single-chai...
Variable-temperature spectroscopic and crystallographic studies on the chromium(II) Tutton’s salts, (MI)2Cr(X2O)6(SO4)2, where MI ) ND4+, Rb+, or Cs+, and X ) H or D, are reported. Inelastic neutron scattering (INS) and multifrequency EPR experiments facilitate a rigorous definition of the ground-state electronic structure from 1.5 up to 296 K, which is unprecedented for a high-spin d4 complex. Modeling of the INS data using a conventional S ) 2 spin Hamiltonian reveals a dramatic variation in the axial and rhombic zero-field-splitting parameters. For the ammonium salt, D and E are -2.454(3) and 0.087(3) cm-1 at 10 K and -2.29(2) and 0.16(3) cm-1 at 250 K, respectively. A temperature variation in the stereochemistry of the [Cr(D2O)6]2+ complex is also identified, with an apparent coalescence of the long and medium Cr-O bond lengt...
Want to know more?If you want to know more about this cutting edge product, or schedule a demonstration on your own organisation, please feel free to contact us or read the available documentation at http://www.keep.pt/produtos/retrievo/?lang=en