Copper(II) coordination compounds based on bis-hydrazones of 2,6-diacetylpyridine: synthesis, structure, and cytotoxic activity.

By reacting a series of 2,6-diacetylpyridine bis-hydrazones containing pyrimidine (H2L1), benzimidazole (H2L2) and phthalazine (H2L3) heterocyclic fragments with copper(II) chloride and bromide, a variety of pentacoordinated complexes of the composition , and , where X = Cl, Br, are formed. The properties and structure of the compounds were studied by means of NMR, IR, UV-vis, ESR, and X-ray absorption spectroscopy, cyclic voltammetry and X-Ray single crystal diffraction methods. It was shown that complexes of the cationic type have an asymmetric structure with a distorted square-pyramidal geometry of the coordination unit.

Excited State Proton Transfers in Hybrid Compound Based on Indoline Spiropyran of the Coumarin Type and Azomethinocoumarin in the Presence of Metal Ions.

Spectral-luminescence properties of a hybrid compound containing a coumarin-type spiropyran and an azomethinocoumarin fragment in toluene-acetonitrile solution in the presence of Li, Ca, Zn and Mg ions are reported. Two excited state proton transfers can occur in the hybrid compound-the transfer of a proton from the OH group of the 7-hydroxy coumarin tautomer to the N atom of the C=N bond of the azomethine fragment leading to green ESIPT fluorescence with a maximum at 540 nm and from the OH group of the 7-hydroxy coumarin tautomer to the carbonyl group of the pyrone chromophore, which leads to the formation of the 2-hydroxyl-tautomer of coumarin with blue fluorescence with a maximum at 475 nm. Dependence of these excited state proton transfers on the metal nature and irradiation with an external UV source is discussed.

Field-induced SIM behaviour of a Co(II) complex with a 1,1'-diacetylferrocene-derived ligand.

Herein, we report the synthesis and magnetic properties of the Co(ii) coordination compound with the 1,1'-bis(1-((pyrid-2-ylmethylene)hydrazono)ethyl)ferrocene (L) ligand, having the general formula [CoLCl2]. The static magnetic data analysis supported by the CASSCF/NEVPT2 calculations revealed the presence of the triaxial magnetic anisotropy with Dexp = +35.2 cm-1 and large rhombicity (E/D = 0.

Field-induced single-ion magnet behaviour of a hexacoordinated Co(ii) complex with easy-axis-type magnetic anisotropy.

A coordination compound with the composition [CoLCl2]·H2O (L = bis-condensation product of diacetyl and 2-hydrazinyl-4,6-dimethylpyrimidine) was synthesized, in which the Co(ii) ion was hexacoordinated. Under applied DC fields, this compound exhibited single-ion magnet behavior. Two relaxation processes were observed when increasing the applied magnetic field from 1000 to 3200 Oe.

Photochromic and luminescence properties of a hybrid compound based on indoline spiropyran of the coumarin type and azomethinocoumarin.

A novel hybrid compound whose molecule includes the photochromic spiropyran fragment and two fluorophores - coumarin and salicylideneimine - was synthesized by the reaction of two equivalents of 8-formyl-7-hydroxy-4-methylcoumarin with 5-amino-1,3,3-trimethyl-2-methyleneindoline. Its spectral-kinetic and fluorescence properties were studied in comparison with model compounds - 7-hydroxy-4-methyl-coumarin, spiropyran of the coumarin type, and azomethinocoumarin in toluene and ethanol. It was shown that the hybrid compound exhibited photochromic transformations in both solvents.

Adsorption studies of divalent, dinuclear coordination complexes as molecular spacers on SWCNTs.

In order to enhance the electrical energy storage capabilities of nanostructured carbon materials, inter-particle spacer strategies are needed to maintain ion-accessible surface area between the nanoparticles. This paper presents a comparison between different classes of divalent, dinuclear coordination complexes which both show strong adsorption to SWCNTs and have molecular spacer properties that maintain electrochemical activity. We find that a novel, dinuclear zinc hydrazone complex binds as an ion-pair at very high loading while not inducing significant aggregation as compared to our previously studies of dinuclear ruthenium complexes.

Excited state intramolecular proton transfer in o-tosylaminobenzaldehyde.

Excited state intramolecular proton transfer (ESIPT) in o-tosylaminobenzaldehyde has been investigated. According to quantum-chemical calculations ESIPT in o-tosylaminobenzaldehyde is barrierless. Product of ESIPT undergoes efficient nonradiative deactivation caused by internal rotation of C(H)OH-group.

Novel hydrazone derivatives of 7-hydroxy-3',3'-dimethyl-3'H-spiro[chromene-2,1'-isobenzofuran]-8-carbaldehyde.

The structures of new oxaindane spiropyrans derived from 7-hydroxy-3',3'-dimethyl-3'H-spiro[chromene-2,1'-isobenzofuran]-8-carbaldehyde (SP1), namely N-benzyl-2-[(7-hydroxy-3',3'-dimethyl-3'H-spiro[chromene-2,1'-isobenzofuran]-8-yl)methylidene]hydrazinecarbothioamide, C(27)H(25)N(3)O(3)S, (I), at 120 (2) K, and N'-[(7-hydroxy-3',3'-dimethyl-3'H-spiro[chromene-2,1'-isobenzofuran]-8-yl)methylidene]-4-methylbenzohydrazide acetone monosolvate, C(27)H(24)N(2)O(4)·C(3)H(6)O, (II), at 100 (2) K, are reported. The photochromically active C(spiro)-O bond length in (I) is close to that in the parent compound (SP1), and in (II) it is shorter. In (I), centrosymmetric pairs of molecules are bound by two equivalent N-H.

A novel chelatofore functionalized spiropyran of the 2-oxaindane series.

A novel chelatofore functionalized spiropyran of the 2-oxaindane series, namely 8-formyl-7-hydroxy-3',3'-dimethylspiro[2H-chromene-2,1'(3'H)-2-benzofuran], C(19)H(16)O(4), is reported. In the crystalline state, dimers are formed as a result of the pi-pi stacking of aromatic groups of the 2H-chromene part of the molecule and C-H..

Synthesis, IR, UV/vis-, (1)H NMR and DFT study of chelatophore functionalized 1,3-benzoxazinone spiropyrans.

Six novel functionalized spiropyran's derivatives of 2H-1,3-benzoxazinone series were synthesized by introducing the substituents with chelating ability into 2H-chromene part of the 8'-formyl-7'-hydroxy-3-methyl-4-oxo-3,4-dihydro-2H-1,3-benzoxazine-2-spiro-2'-[2H]-chromene (I) by condensation with 2-aminophenol, 2-amino-4-methylphenol, 2-amino-4-nitrophenol, 2-amino-1-methylbenzimidazole, 4-amino-4H-1,2,4-triazole, N-(4-aminophenyl)acetamide. (1)H NMR, UV/vis, IR spectroscopy combined with quantum-chemical calculations employing density functional theory (DFT) were used to study their structure. All substances, except 2-amino-4-nitrophenol derivative exist in solid state and in solution solely in closed spiroform, while the mentioned one undergoes partial spiropyran ring opening.