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The possibility of the complex formation of three bispidines with copper(ii) chloride and acetate in a deuterated DMF solution was studied by NMR titration. For all ligands, the formation of complexes with copper(ii) chloride was clearly detected based on the changes in the signals in the proton NMR spectra. The formation of complexes with copper(ii) acetate was not observed for any of the ligands. The results of the study can be used in the design of metal complex catalysts for the Henry reaction. [ABSTRACT FROM AUTHOR]

A method for the preparation of new organic ligands combining in their structure a 2-(pyridin-2-yl)benzothiazole moiety capable of coordinating metal iones and a thioacetate group, which makes it possible to adsorb the obtained compounds on a gold surface, has been developed. Using cyclic voltammetry, the possibility of chemisorption of the obtained compounds on the surface of gold electrodes and obtaining complexes of adsorbed ligands with CuCl2 has been shown. [ABSTRACT FROM AUTHOR]

The reaction of copper(ii) acetate with 2-furancarboxylate (Hfur, pyromucate) anions and the N-donor ligands 4-phenylpyridine (phpy) and 3-aminopyridine (NH2py) in acetonitrile afforded the mononuclear complexes of the composition [Cu(fur)2(phpy)2(H2O)] · phpy (1) and [Cu(fur)2(NH2py)2] (2), respectively. The structures of the complexes were established by X-ray diffraction. The simultaneous thermal analysis of the thermal behavior of complex 1 showed that this complex is thermally stable up to 125 °C. The in vitro biological activity of complexes 1 and 2 was evaluated against the non-pathogenic mycobacterial Mycolicibacterium smegmatis strain. [ABSTRACT FROM AUTHOR]

An approach for the synthesis of new organic ligands combining in their structure pyridine, benzothiazole, and polyethylene glycol fragments was developed, proceeding from 6-hydroxy-2-(pyridin-2-yl)benzothiazole and mono- or ditosyl-substituted polyethylene glycols. The ligand 2-(2-{[2-(pyridin-2-yl)benzothiazol-6-yl]oxy}ethoxy)ethanol (L) in the reaction with Cu(ClO4)2•6 H2O and CuCl2•2 H2O formed coordination compounds of the composition L2Cu(ClO4)2•7 H2O and LCuCl2•0.5 H2O, respectively. [ABSTRACT FROM AUTHOR]

The homochiral coordination polymers [Cu4(CH3OH)(H2O)4(Hbtb)(S-mal)2]•4H2O and [Cu4(CH3OH)(H2O)4(Hbtb)(R-mal)2]•4H2O were synthesized by heating S- or R-malic acid (H3mal), 4,4′,4″-benzene-1,3,5-triyltris(benzoic acid) (H3btb), and copper(II) acetate in an aqueous methanolic solution. The reaction with copper(II) nitrate in aqueous dioxane afforded the coordination framework [Cu6(C4H8O2)3(H2O)3(btb)4]•4C4H8O2•10H2O, which does not contain chiral ligands. The compositions and crystal structures of the new compounds were determined by single-crystal X-ray diffraction and confirmed by X-ray powder diffraction, IR spectroscopy, thermogravimetric and elemental analysis. [ABSTRACT FROM AUTHOR]

5-Formylpyrrolyl-substituted nitronyl and imino nitroxide radicals HL and HL were synthesized. Their solid phases are formed by packing pairs of the molecules. In the {HL...HL} pairs, the dominant interaction is the ferromagnetic exchange with J/kB = 8.8 K (Hamiltonian $$H = 2J\left( {\overrightarrow {{s_1}} \overrightarrow {{s_2}} } \right)$$ ). The ferromagnetic exchange occurs also in the heterospin molecules [Ni(L)], [Cu(L)], and [Ni(L)(MeOH)]. In the complexes [Ni(L)] and [Cu(L)], a small change in the mutual orientation of the coordinated ligands has a considerable effect on the value and the sign of the energy of exchange interactions between the unpaired electrons of the metal ion and paramagnetic ligands. [ABSTRACT FROM AUTHOR]

Novel polydentate ligands were obtained from second and third generation hyperbranched polyesters containing terminal (3-diethylamino)propionate groups. Polynuclear Cu complexes with these ligands were synthesized. The degree of diethylamination of the polyesters increases when moving from the second to the third generation (from 56 to 81%). In polynuclear complexes, the ratios of Cu to hyperbranched ligand are 6 : 1 and 13 : 1 for second and third generation polyester polyamines, respectively. It was demonstrated using IR and ESR spectroscopy that each coordination polyhedron in the complexes is an isolated paramagnetic center of the formula CuNOSolv (Solv = HO, DMSO). [ABSTRACT FROM AUTHOR]

The synthesis, structure, and magnetic properties of the products of the reaction for Cu(hfac) (hfac is hexafluoroacetylacetonate) with spin-labeled nitronyl nitroxides 4,4,5,5-tetramethyl-2-(1-R-1 H-pyrazol-5-yl)-3-imidazoline-1-oxyl 3-oxides L (R = Me, Et, Pr, Bu), viz., binuclear complex [Cu(hfac)L] and chain polymer complexes [Cu(hfac)L], are described. The polymer heterospin chains are built according to 'head-to-head' (R = Me, Et, Pr, Bu) and 'head-to-tail' (R = Pr, Bu) motifs. Compound [Cu(hfac)L] is characterized by the ability to reveal the reversible effect of thermally induced spin transition at a temperature about 75 K (without hysteresis). In the set of heterospin Cu compounds with spin-labeled pyrazoles, this is the earlier unknown example of a molecular complex exhibiting a similar magnetic anomaly. [ABSTRACT FROM AUTHOR]

The temperature dependence of the heat capacity of a polycrystalline sample of the heterospin solvate [Cu(hfac)L]·0.5[1,4-(CF)CH] (L is 2-(1-butyl-1 H-pyrazol-4-yl)-4,4,5,5-tetramethyl-4,5-dihydro-1 H-imidazole-3-oxide 1-oxyl) was studied in the range of 5-298 K. The results of the thermochemical study of this compound were shown to be in agreement with the data from magnetochemical and diffraction measurements providing evidence that, as the temperature changes, the complex undergoes phase transitions at 59 and 123 K. [ABSTRACT FROM AUTHOR]

A reaction of (HPiv)Cu(Piv) with dimethylmalonic acid dipotassium salt (KMemal) leads to the formation of a cage coordination polymer {(μ-HO)K[(μ-HO)Cu-(μ,κ-Memal)(μ,κ-Memal)][Cu(μ,κ-Memal)(μ,κ-Memal)]} n ( 1). It was found that when 1 reacted with CdSO·8HO in a mixture of EtOH-HO (3: 1), the potassium ions in 1 were displaced with cadmium( ii) ions with the formation of a heterometallic 1D-polymer [(κ-HO)CdCu(μ,κ-Memal)] ( 2). Compounds 1 and 2 were characterized by X-ray crystallography and ESR spectroscopy. [ABSTRACT FROM AUTHOR]

To find the factors favorable for the appearance of chemomechanical activity of heterospin crystals, a series of new heterospin complexes were synthesized and characterized. It includes [Cu(tfac)L]·2CHCl, [Cu(tfac)L]·2EtOH, [[Cu(pfu)]L]·1/2CHCl, [Cu(pfh)L]·1/2CHCl, [Cu(piv)L]·2MeOH, [Co(piv)L], [ $$ Cu(hfac)_2 L^{CD_3 } _2 $$], [Cu(hfac)L]·CHCl, and [Cu(hfac)L] (L, $$ L^{CD_3 } $$, and L are N-methylimidazolyl-, N-trideuteriomethylimidazolyl-, and N-methyltriazolyl-substituted nitronyl nitroxides, respectively; tfac, hfac, pfu, pfh, and piv are the charged coordinated diamagnetic ligands 1,1,5,5-tetrafluoropentane-2,4-dionate, 1,1,1,5,5,5-hexafluoropentane-2,4-dionate, 1,1,1,2,2,3,3,4,4,8,8,9,9,10,10,11,11,11-octadecafluoroundecane-5,7-dionate, 1,1,1,5,5,6,6,6-octafluorohexane-2,4-dionate, and 2,2-dimethylpropionate, respectively). The crystal and molecular structures of all compounds were determined. The results of the X-ray diffraction study of the complex [Ni(hfac)L] synthesized earlier are reported. In the solid state of the complexes [Cu(pfh)L] and [Co(piv)L], the paramagnetic ligands are cis-coordinated to the central atom in a monodentate fashion via the donor N atom of the imidazole ring. In the dinuclear complexes [[Cu(pfu)]L] and [Cu(hfac)L], the paramagnetic ligands are also in cis positions but act as bridges through coordination of the donor N atoms of the azole ring and the O atom of the nitronyl nitroxide moiety to different Cu ions. In the solid complexes $$ Cu(hfac)_2 L^{CD_3 } _2 $$ , [Cu(hfac)L], [Cu(tfac)L]·2CHCl, [Cu(tfac)L]·2EtOH, and [Cu(piv)L]·2MeOH, the nitronyl nitroxide radicals in the mononuclear heterospin molecules are in trans positions. The packing motif in the crystal structures of the complexes $$ Cu(hfac)_2 L^{CD_3 } _2 $$ , [Cu(tfac)L]·2CHCl, and [Cu(tfac)L]·2EtOH is the same as that in the previously studied complexes [M(hfac)L] exhibiting chemomechanical activity. Among the complexes under consideration, only crystals of $$ Cu(hfac)_2 L^{CD_3 } _2 $$ can exhibit chemomechanical activity, that is to make jumps upon heating or irradiation. The results of the present study suggest that the packing of the solid-state structure plays a key role in the generation of mechanical activity of the crystals. [ABSTRACT FROM AUTHOR]

The condensation of ethyl 2-[(2-aminophenyl)aminomethylidene]-3-oxo-3-polyfluoroalkyl-propionates with aldehydes (salicylaldehyde, furfural, and benzaldehyde) affords the corresponding azomethine derivatives exhibiting the complexing ability toward copper and nickel ions. [ABSTRACT FROM AUTHOR]

Diethyl 2,2′ [1,2-phenylenebis(aminomethylidene)]bis(3-oxo-3-polyfluoroalkylpropionates) were synthesized by the condensation of a double excess of ethyl 2-ethoxymethylidene- 3-oxo-3-polyfluoroalkylpropionates with o-phenylenediamine. The use of equimolar ratios of the starting reactants affords ethyl 2-[(2-aminophenyl)aminomethylidene]-3-oxo- 3-polyfluoroalkylpropionates from which nonsymmetric biscondensation products were synthesized by the reaction with related reactants containing different polyfluoroalkyl substituent. The copper(II), nickel(II), and cobalt(II) complexes were obtained on the basis of new ligands. [ABSTRACT FROM AUTHOR]

reaction of CuCl with a chiral Schiff base (HL) derived from (+)-6h-pinene leads to paramagnetic complex Cu(HL)Cl (1) (fu = 2.03 fuB) and solvate Cu(HL)Cl•MeCN (2) (fueff = 1.87 fuB). Monocrystals of hydrate [Cu(HL)Cl]•HO (3) were grown for the X-ray diffraction study, which showed that the crystal structure of 3 consists of the molecules of a mononuclear complex [Cu(HL)Cl] containing tridentate chelating ligand HL-, and water molecules. Coordination polyhedron ClNO is a distorted tetrahedron. Intermolecular con- tacts in the structure 3 lead to the formation of supramolecular chains, parallel to the axis -6h. Compounds 1 and 2 were studied by ESR and IR spectroscopy. [ABSTRACT FROM AUTHOR]

Three new homochiral metal-organic coordination polymers [Cucamphdabco] · DMF•2HO, [Cucamphbipy] · 3DMF•2HO, and [Cucamphbpe] · 4DMF•2HO (Hcamph is (+)-camphoric acid, bipy is 4,4'-bipyridyl, bpe is trans-bis(4-pyridyl)ethylene) were synthesized by heating copper(II) nitrate, (+)-camphoric acid, and N-donor ligands of different length (dabco, bipy, bpe) in DMF and characterized by powder X-ray diffraction, IR spectroscopy, and TGA. The obtained compounds are isostructural with the previously reported porous zinc(II) camphorates. [ABSTRACT FROM AUTHOR]

A series of cyclic and acyclic diamido-bis-sulfide ligands were synthesized by N-acylation of 1,2-bis(2-aminophenylthio)ethane and 1,4-bis(2-aminophenylthio)butane with acetic, malonic, and 3,3′-dithiodipropionic acid chlorides or esters. The complexation of obtained ligands with CuII, NiII, and CoII salts in solution and on the gold electrode surface was studied. The formation of complexes of these ligands with copper(II) chloride in DMF is irreversible and accompanied by deprotonation of the amide nitrogen atoms. [ABSTRACT FROM AUTHOR]

The synthesis and structure of binuclear copper(II) complexes with acyldihydrazones of some β-diketones are described. The molecular structure of the copper(II) complex [Cu2L·4Py] with trifluoroacetylacetone succinyldihydrazone (H4L) was determined by the single-crystal X-ray analysis. Central atoms are bridged by a chain of seven σ-bonds with a Cu...Cu distance of 8.750 Å. EPR spectra of copper(II) complexes with acyldihydrazones of trifluoroacetylacetone and lower dicarboxylic acids containing from one to four methylene groups in the aliphatic spacer show the seven-line HFS due to spin-spin coupling of unpaired electrons with the two equivalent copper nuclei ( g = 2.110, a = (38.5–40.5)⊙10−4 cm−1). By extending polymethylene spacer, as well as by modifying starting β-diketone, an exchange interaction between paramagnetic centers is suppressed. [ABSTRACT FROM AUTHOR]

Tetradentate N4-type organic ligands containing two 5-(2-pyridylmethylidene)-2-thio-3,5-dihydro-4 H-imidazol-4-one fragments linked by two-, four-, or six-carbon polymethylene bridges between the sulfur atoms were synthesized. Mono- and dinuclear complexes of these ligands with copper(II) chloride, as well as with copper(I) and copper(II) perchlorates, were prepared. The structure of the coordination compound (5 Z,5′ Z)-2,2′-(butane-1,2-diyl-disulfanyldiyl)bis-5-(2-pyridylmethylidene)-3-phenyl-3,5-dihydro-4 H-imidazol-4-one with copper(I) perchlorate was established by X-ray diffraction. The copper atom in this complex is in a distorted tetrahedral coordination formed by four nitrogen atoms of two imidazole and two pyridine rings. The perchlorate anion is located in the outer sphere of the complex and is not involved in the coordination with the copper ion. The electrochemical study of the ligands and the complexes was carried out by cyclic voltammetry and rotating disk electrode voltammetry. The initial reduction of the complexes under study occurs at the metal atom. The length of the polymethylene bridge in the ligand has only a slight effect on the redox properties of the ligands and the complexes. [ABSTRACT FROM AUTHOR]

Tetradentate N4-type organic ligands containing two 5-(2-pyridylmethylidene)-2-thio-3,5-dihydro-4 H-imidazol-4-one fragments linked by two-, four-, or six-carbon polymethylene bridges between the sulfur atoms were synthesized. Mono- and dinuclear complexes of these ligands with copper(II) chloride, as well as with copper(I) and copper(II) perchlorates, were prepared. The structure of the coordination compound (5 Z,5′ Z)-2,2′-(butane-1,2-diyl-disulfanyldiyl)bis-5-(2-pyridylmethylidene)-3-phenyl-3,5-dihydro-4 H-imidazol-4-one with copper(I) perchlorate was established by X-ray diffraction. The copper atom in this complex is in a distorted tetrahedral coordination formed by four nitrogen atoms of two imidazole and two pyridine rings. The perchlorate anion is located in the outer sphere of the complex and is not involved in the coordination with the copper ion. The electrochemical study of the ligands and the complexes was carried out by cyclic voltammetry and rotating disk electrode voltammetry. The initial reduction of the complexes under study occurs at the metal atom. The length of the polymethylene bridge in the ligand has only a slight effect on the redox properties of the ligands and the complexes. [ABSTRACT FROM AUTHOR]

The structure of the copper(ii) complex with dithizone (H2Dz) was studied by ESR spectroscopy. The lines of the ESR spectra of the Cu(HDz)2 complex in solutions are so broad that the superhyperfine structure (SHFS) from the ligand atoms is unobservable and even the hyperfine structure (HFS) from the copper nuclei is poorly resolved. In polycrystalline magnetically dilute powders with the ratio Ni(HDz)2 : Cu(HDz)2 = 60 : 1, the SHFS from the N atoms is well resolved in both perpendicular and parallel orientations. The copper(ii) complex with dithizone has a square-planar structure in both liquid solutions and Ni(HDz)2 matrix. Reasons for the unusual linewidths in the ESR spectra of Cu(HDz)2 are discussed. [ABSTRACT FROM AUTHOR]

The structure of CuII complexes with hydroxamic acids Cu[R1N(O)−(O)CR2]2, where R1=Ph, R2=Me; R1=Me, R2=Ph, was studied by ESR spectroscopy. In toluene solutions and low-temperature glasses, the complexes exist as two forms, which were identified as cis-and trans-isomers. The proportions of the isomers were determined. [ABSTRACT FROM AUTHOR]

2-Propanol or 1-propanol in acetonitrile, when exposed to air and irradiated with a tungsten lamp in the presence of catalytic amounts of copper( ii) acetate and hydroquinone, are oxidized to give acetone or propanal, respectively. [ABSTRACT FROM AUTHOR]