Tris(1,10-phenanthroline-κ2 N,N′)iron(II) bis­[(1,10-phenanthroline-κ2 N,N′)tetra­kis­(thio­cyanato-κN)chromate(III)] acetonitrile tris­olvate monohydrate

Single crystals of the title heterometallic compound, [Fe(C12H8N2)3][Cr(NCS)4(C12H8N2)]2·3CH3CN·H2O or [Fe(Cphen)3][Cr(NCS)4(phen)]2·3CH3CN·H2O, were pre­pared using the one-pot open-air reaction of iron powder, Reineckes salt and 1,10-phenanthroline (phen) in acetonitrile. The asymetric unit consists of an [Fe(phen)3]2+ cation, two [Cr(phen)(NCS)4]− anions, three acetonitrile solvent mol­ecules and a water mol­ecule. The Fe and Cr atoms both show a slightly distorted octa­hedral FeN6 and CrN6 coordination geometry with adjacent angles in the range 79.67 (12)–95.21 (12)°. No classical hydrogen bonding involving the water molecule is observed

Hexa­kis­(dimethyl­formamide-κO)manganese(II) (dimethyl­formamide-κO)pentakis(­thio­cyanato­-κN)chromate(III)

The title compound, [Mn(C3H7NO)6][Cr(NCS)5(C3H7NO)], was obtained unintentionally as a product of an attempted synthesis of heterometallic complexes based on Reineckes anion using manganese powder, Reineckes salt and 1-(2-hy­droxy­eth­yl)tetra­zole as starting materials. The crystal structure of the complex consists of an [Mn(dmf)6]2+ cation and a [Cr(NCS)5(dmf)]2− anion (dmf = dimethyl­formamide). The MnII and CrIII atoms show a slightly distorted octa­hedral MnO6 and CrN5O coordination geometries with adjacent angles in the range 85.29 (13)–95.96 (14)°

Diammine(2,2′-bipyridine)­bis(thio­cyan­ato­-κN)cobalt(III) diamminetetra­kis(thio­cyanato­-κN)chromate(III) aceto­nitrile disolvate

The new heterometallic title complex, [Co(NCS)2(C10H8N2)(NH3)2][Cr(NCS)4(NH3)2]·2CH3CN, has been prepared using the open-air reaction of cobalt powder, Reineckes salt and 2,2′-bipyridine (dpy) in acetonitrile. The crystal structure consists of discrete cationic [Co(NCS)2(NH3)2(dpy)]+ and anionic [Cr(NCS)4(NH3)2]− building blocks, both with 2 symmetry, and acetonitrile solvent mol­ecules, which are linked together by N—H⋯N hydrogen bonds, forming extended supra­molecular chains. Furthermore, N—H⋯S, C—H⋯S and C—H⋯N hydrogen bonds inter­link neighbouring chains into a three-dimensional framework. The Co atom is in an elongated octa­hedral coordination environment with two N atoms from the dpy ligands and two NCS-groups in the equatorial plane and with two NH3 mol­ecules at the axial positions. The CrIII ion is octa­hedraly coordinated by two NH3 mol­ecules at the axial positions and four NCS-groups in the equatorial plane. Intensity statistics indicated non-merohedral twinning with the twin matrix [100; 00; 0]. The refined ratio of the twin components is 0.530 (1):0.470 (1)

Bis{μ2-2-[(2-hy­droxy­eth­yl)(meth­yl)amino]­ethano­lato}bis­(μ3-N-methyl-2,2′-aza­nediyldiethano­lato)tetra­kis­(thio­cyan­atato-κN)dichromium(III)dimanganese(II) dimethyl­formamide tetra­solvate

The heterometallic title complex, [Cr2Mn2(C5H11NO2)2(C5H12NO2)2(NCS)4]·4C3H7NO, was prepared using manganese powder, Reineckes salt, ammonium thio­cyanate and a non-aqueous solution of N-methyl­diethano­lamine in air. The centrosymmetric mol­ecular structure of the complex is based on a tetra­nuclear {Mn2Cr2(μ-O)6} core. The tetra­nuclear complex mol­ecule and the two uncoordinated dimethyl­formamide mol­ecules are linked by O—H⋯O hydrogen bonds, while the two other mol­ecules of dimethyl­formamide do not participate in hydrogen bonding

Investigação do efeito reparador do gel de ectoína em modelo de queima térmica

Due to the ability to create complexes of water molecules on the surface of the mucous membrane, ectoine is a promising compound for the treatment of burns. In male rats (n=30), 2 thermal burns were counteracted under counter-anesthesia, one of which was treated by topical application of the test drugs for 7 days, and the other served as a control. On the 8th day, skin samples in the area of the burn were taken for morphological examination. Histological sections were then scored by independent experts. The best histological picture of thermally damaged tissues was demonstrated by animals receiving ectoine. A less significant, but pronounced reparative effect was observed in histological samples of the actovegin group. The least significant reparative effect was demonstrated by contractubex. Ectoine improved the histological picture, improved repair and reduced the inflammatory response of the tissues and can be recommended for further preclinical studies as a treatment for burns.Debido a la capacidad de crear complejos de moléculas de agua en la superficie de la membrana mucosa, la ectoina es un compuesto prometedor para el tratamiento de las quemaduras. En ratas macho (n = 30), 2 quemaduras térmicas se contrarrestaron con contraestesia, una de las cuales se trató mediante la aplicación tópica de los fármacos de prueba durante 7 días, y la otra sirvió como control. En el octavo día, se tomaron muestras de piel en el área de la quemadura para un examen morfológico. Las secciones histológicas fueron calificadas por expertos independientes. El mejor cuadro histológico de los tejidos dañados térmicamente fue demostrado por los animales que recibieron ectoína. Se observó un efecto reparador menos significativo, pero pronunciado en muestras histológicas del grupo actovegin. El efecto reparador menos significativo fue demostrado por contractubex. Ectoine mejoró el cuadro histológico, mejoró la reparación y redujo la respuesta inflamatoria de los tejidos y puede recomendarse para estudios preclínicos adicionales como tratamiento para las quemaduras.Devido à capacidade de criar complexos de moléculas de água na superfície da membrana mucosa, a ectoína é um composto promissor para o tratamento de queimaduras. Em ratos machos (n = 30), duas queimaduras térmicas foram combatidas sob anestesia, uma das quais foi tratada por aplicação tópica das drogas de teste por 7 dias, e a outra serviu como controle. No oitavo dia, amostras de pele na área da queimadura foram retiradas para exame morfológico. As secções histológicas foram então classificadas por especialistas independentes. O melhor quadro histológico dos tecidos termicamente lesados foi demonstrado pelos animais que receberam ectoína. Um efeito reparador menos significativo, mas pronunciado, foi observado em amostras histológicas do grupo da actovegina. O efeito reparador menos significativo foi demonstrado pelo contratoubex. Ectoine melhorou o quadro histológico, melhorou o reparo e reduziu a resposta inflamatória dos tecidos e pode ser recomendado para estudos pré-clínicos adicionais como tratamento para queimaduras

Diaqua­bis­(propane-1,3-diamine)­copper(II) bis­[diamminetetra­kis­(thio­cyanato-κN)chromate(III)] dimethyl sulfoxide octa­solvate

The ionic title complex, [Cu(C3H10N2)2(H2O)2][Cr(NCS)4(NH3)2]·8C2H6OS, consists of complex [Cu(dipr)2(H2O)2]2+ copper cations (dipr is propane-1,3-diamine), complex [Cr(NCS)4(NH3)2]− anions and uncoord­inated solvent dimethyl sulfoxide (DMSO) mol­ecules. All the metal atoms lie on crystallographic centers of symmetry. The cations are connected to the anions through N—H⋯O hydrogen bonds between the NH3 mol­ecules of the anion and the water mol­ecules of the cation. The DMSO mol­ecules are involved in hydrogen-bonded linkage of the [Cr(NCS)4(NH3)2]− anions into supra­molecular chains through bridging O atoms. A network of hydrogen bonds as well as short S⋯S contacts [3.5159 (12) and 3.4880 (12) Å] between the NCS groups of the complex anions link the mol­ecules into a three-dimensional supra­molecular network

Polynuclear Cobalt Complexes as Catalysts for Light-Driven Water Oxidation: A Review of Recent Advances

Photochemical water oxidation, as a half-reaction of water splitting, represents a great challenge towards the construction of artificial photosynthetic systems. Complexes of first-row transition metals have attracted great attention in the last decade due to their pronounced catalytic efficiency in water oxidation, comparable to that exhibited by classical platinum-group metal complexes. Cobalt, being an abundant and relatively cheap metal, has rich coordination chemistry allowing construction of a wide range of polynuclear architectures for the catalytic purposes. This review covers recent advances in application of cobalt complexes as (pre)catalysts for water oxidation in the model catalytic system comprising [Ru(bpy)3]2+ as a photosensitizer and S2O82− as a sacrificial electron acceptor. The catalytic parameters are summarized and discussed in view of the structures of the catalysts. Special attention is paid to the degradation of molecular catalysts under catalytic conditions and the experimental methods and techniques used to control their degradation as well as the leaching of cobalt ions

Tetranuclear Copper Complexes with Bulky Aminoalcohol Ligands as Catalysts for Oxidative Phenoxazinone Synthase-like Coupling of Aminophenol: A Combined Experimental and Theoretical Study

The new copper(II) complexes [Cu4(pa)4(Bae)4]·H2O (1) and [Cu4(eba)4(Buae)4]·H2O (2) (Hpa = propionic acid, HBae = 2-benzylaminoethanol, Heba = 2-ethylbutyric acid and HBuae = 2-butylaminoethanol) were synthesizsed by the interaction of a copper salt with a methanol solution of the respective ligands. The single-crystal X-ray diffraction analysis reveals that both compounds have a {Cu4(μ3-O)4} cubane-like core. Both compounds show pronounced phenoxazinone synthase-like activity towards the aerobic oxidation of o-aminophenol to phenoxazinone chromophore, with the maximum initial rates W0 up to 3.5 × 10−7 M s−1, and exhibit complex non-linear W0 vs. [catalyst]0 dependences. DFT//CCSD theoretical calculations (B3LYP/ma-def2-TZVP//DLPNO-CCSD(T)/ma-def2-TZVPP) were employed to investigate the most challenging steps of catalyst-free and copper-catalysed o-aminophenol oxidation (formation of o-aminophenoxyl radical). QTAIM analysis was used to study the key intermediates and weak interactions. Geometries and energies of intermediates and transition states were benchmarked against a series of popular DFT functionals. The results of the calculations demonstrate that a CuII–OO• copper-superoxo model catalyst decreases the calculated activation barrier from 28.7 to 19.9 kcal mol−1 for the catalyst-free and copper-catalysed abstraction of the H atom from the hydroxyl group of o-aminophenol, respectively. Finally, both complexes 1 and 2 were studied as catalysts in the amidation of cyclohexane with benzamide to give N-cyclohexyl benzamide and N-methyl benzamide employing di-tert-butyl peroxide (DTBP) as the oxidant, with a conversion of 16%, and in the oxidation of cyclohexane to cyclohexanol with aq. H2O2, with a conversion of 12%

Novel H-Bonded Synthons in Copper Supramolecular Frameworks with Aminoethylpiperazine-Based Ligands. Synthesis, Structure and Catalytic Activity

New Schiff base complexes [Cu2(HL1)(L1)(N3)3]∙2H2O (1) and [Cu2L2(N3)2]∙H2O (2) were synthesized. The crystal structures of 1 and 2 were determined by single-crystal X-ray diffraction analysis. The HL1 ligand results from the condensation of salicylaldehyde and 1-(2-aminoethyl)piperazine, while a new organic ligand, H2L2, was formed by the dimerization of HL1 via a coupling of two piperazine rings of HL1 on a carbon atom coming from DMF solvent. The dinuclear building units in 1 and 2 are linked into complex supramolecular networks through hydrogen and coordination bondings, resulting in 2D and 1D architectures, respectively. Single-point and broken-symmetry DFT calculations disclosed negligible singlet–triplet splittings within the dinuclear copper fragments in 1 and 2. Catalytic studies showed a remarkable activity of 1 and 2 towards cyclohexane oxidation with H2O2 in the presence of nitric acid and pyridine as promoters and under mild conditions (yield of products up to 21%). Coordination compound 1 also acts as an active catalyst in the intermolecular coupling of cyclohexane with benzamide using di-tert-butyl peroxide (tBuOOtBu) as a terminal oxidant. Conversion of benzamide at 55% was observed after 24 h reaction time. By-product patterns and plausible reaction mechanisms are discussed

Tris(2,2′-bipyridine)copper(II) pentacyanidonitrosoferrate(II) methanol disolvate monohydrate

The title complex [Cu(C10H8N2)3][Fe(CN)5(NO)]·2CH3OH·H2O, consists of discrete [Cu(bpy)3]2+ cations (bpy is 2,2′-bipyridine), [Fe(CN)5NO]2− anions and solvent molecules of crystallization (two methanol molecules and one water molecules per asymmetric unit). The CuII ion adopts a distorted octahedral environment, coordinated by six N atoms from three bpy ligands. The cation charge is balanced by a nitroprusside counter-anion, which has a slightly distorted octahedral coordination geometry. In the crystal, anions and solvent molecules are involved in O—H...N and O—H...O hydrogen bonds, which form chains along [100]. The cations are located between these chains