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The solvent‐ and catalyst free synthesis of two β‐thio ketones L1a and L1b is reported. L1a, L1b, and a β‐seleno ketone L1c were successfully employed as ligand precursors in the synthesis of a novel series of cationic titanium complexes 4a–4c via a well‐established reaction sequence: insertion of the carbonyl functional group into the polarized Ti–Cq,exo bond of the monopentafulvene complex Cp*Ti(Cl)(π‐η5:σ–η1‐C5H4=CR2) (1) (CR2 = adamantylidene), subsequent methylation, and final activation with B(C6F5)3. The cationic titanium complexes 4a–4c bear twofold functionalized cyclopentadienyl [Cp,O,Ch (Ch = S, Se)] ligand frameworks built directly in the coordination sphere of the metal, in which the chalcogen ether functionalities do not coordinate to the central metal atoms as demonstrated by NMR experiments. Consequently, Cp,O σ,π chelating ligand systems are formed with free coordination sites at the central titanium atoms and pendant chalcogen ether moieties. [ABSTRACT FROM AUTHOR]

Starting from the [PtCl(η1-C2H4OMe)(phen)] (phen = 1,10-phenanthroline, 1) platinum(II) precursor, we synthesized and characterized by multinuclear NMR new [Pt(η1-C2H4OMe)(L)(phen)]+ (L = NH3, 2; DMSO, 3) complexes. These organometallic species, potentially able to interact with cell membrane organic cation transporters (OCT), violating some of the classical rules for antitumor activity of cisplatin analogues, were evaluated for their cytotoxicity. Interestingly, despite both complexes 2 and 3 resulting in greater cell uptake than cisplatin in selected tumor cell lines, only 3 showed comparable or higher antitumor activity. General low cytotoxicity of complex 2 in the tested cell lines (SH-SY5Y, SK-OV-3, Hep-G2, Caco-2, HeLa, MCF-7, MG-63, ZL-65) appeared to depend on its stability towards solvolysis in neutral water, as assessed by NMR monitoring. Differently, the [Pt(η1-C2H4OMe)(DMSO)(phen)]+ (3) complex was easily hydrolyzed in neutral water, resulting in a comparable or higher cytotoxicity in cancer cells with respect to cisplatin. Further, both IC50 values and the uptake profiles of the active complex appeared quite different in the used cell lines, suggesting the occurrence of diversified biological effects. Nevertheless, further studies on the metabolism of complex 3 should be performed before planning its possible use in tissue- and tumor-specific drug design.

Cationic lanthanide complexes [Ln(CH 3 CN) 9 ] 3+ [(AlCl 4 ) 3 ] 3– ·CH 3 CN served as efficient catalysts for the tandem Friedel–Crafts alkylation/ketalization reaction of 2-hydroxychalcones with naphthols/substituted phenols to produce diaryl-fused 2,8-dioxabicyclo[3.3.1]nonanes in moderate to high yields. The high catalytic efficiency of the cationic lanthanide complex [Yb(CH 3 CN) 9 ] 3+ [(AlCl 4 ) 3 ] 3– ·CH 3 CN compared with that of YbCl 3 can be attributed to the increased Lewis acidity of the Yb species as a result of cation formation. [ABSTRACT FROM AUTHOR]

A new {[Cu(4,4′-BP) 2 .(H 2 O) 4 ].2,6-NDC.3(H 2 O)} complex has been synthesized by refluxing Cu(NO 3 ) 2 , 2,6-NDC and 4,4′-BP (1:1:1 ratio) (2,6-NDC = 2,6-Naphthalene Dicarboxylic acid, 4,4′-BP = 4,4'-bipyridine) in methanol/ammonia mixture and characterized by various spectroscopic techniques. The geometry around Cu 2+ ion is typical octahedral in cationic complex, while the deprotonated 2,6-NDC act as a charge balancing counter anionic part. Water molecules (lattice and coordinated) also play important role in the self-assembly by forming H bonded supramolecular architecture involving strong inter/intramolecular secondary interactions. The luminescence property and thermogravimetric analyses were also investigated. Both the intermolecular interactions of molecular and crystal structures of this complex were compared and discussed using Hirshfeld surface analysis and 2D-fingerprint plots. Hirshfeld surface analysis indicates that H⋯H, O⋯H and π···π contacts can account for 40.4, 19.3 and 7.7% respectively of the total Hirshfeld surface area. The DFT calculation at the CAM-B3LYP level of theory revealed the existence of three hydrogens binds in the complex. These hydrogen bonds exist between the oxygen atom of ligand and the hydrogen of coordinated water molecules. [ABSTRACT FROM AUTHOR]

Complex [Cu(HL)]Cl ⋅ 1.34 НО (HL = p-( t-Bu)CHCONHN(Me)) is studied by X-ray diffraction analysis. The coordination polyhedron of the copper atom is a distorted tetragonal pyramid, whose base is formed by the amine N and O atoms of two ligands HL, and one of the chlorine atoms occupies the vertex. The second chlorine atom does not enter into the coordination sphere of copper but is linked through an intramolecular hydrogen bond with the NH group. Reagent HL forms a five-membered metallocycle with the central atom. The metallocycle exists in an envelope conformation with the copper atom in the flap. CIF file CCDC no. 1453151. [ABSTRACT FROM AUTHOR]

[Display omitted] • New series of Pt(II) complexes of the type [Pt(η1-CH 2 -CH 2 -OR)(DMSO)(phen)]+ (R = alkyl). • Synthesis of organometallic complexes with the phen and DMSO carrier ligands. • Comparative evaluation of the cytotoxic activity of the new organometallic complexes. The new series of [Pt(η1-CH 2 -CH 2 -OR)(DMSO)(phen)]Cl {R = Me (1b), Et (2b), Pr (3b), Bu (4b), phen = 1,10-phenanthroline} complexes was synthesized starting from the corresponding [PtCl(η1-CH 2 -CH 2 -OR)(phen)] {R = Me (1a), Et (2a), Pr (3a), Bu (4a)} precursors. In the series only complex 1b was previously studied for its potential antitumor activity. In this work, the relative cytotoxicity of 1b - 4b and cisplatin complexes was studied on HeLa, Hep-G2, SH-SY5Y and SK-OV-3 cancer cells. In this way, the effect of R alkyl chain length in modulating cytotoxicity was evidenced. Complex 2b with the Et moiety resulted to be generally more cytotoxic in the tested series of complexes for used cell lines and in particular for the Hep-G2 hepatocarcinoma cells. This approach opens new perspectives for the structural optimization and development of new antitumor drugs. [ABSTRACT FROM AUTHOR]

Novel cationic complex compound of Ru(III) with indazole and Schiff base derived from 5-chlorosalicylaldehyde and aniline has been synthesized. Formulation and characterization of the complex was performed using CHN analysis, MALDI-TOF/TOF mass spectrometry, FT-IR spectroscopy and UV/Visible spectrophotometry. In the octahedral environment of Ru(III), coordination of bidentate Schiff bases occurs through azomethine nitrogen and deprotonated phenolic oxygen while in indazole via nitrogen atom. The interaction of the complex with CT DNA (calf thymus DNA) was carried out under physiological conditions using spectrophotometric titration. [ABSTRACT FROM AUTHOR]

Highlights: [•] Two polymorphs of the the iodo-bridged title compound were synthesized. [•] The polymorphs of the title compound have been characterized using DSC, IR and NMR. [•] The single crystal X-ray structures of both are reported and discussed. [•] The two polymorphs have very different molecular geometries. [ABSTRACT FROM AUTHOR]

Abstract: A highly ordered two-dimensional hybrid magnetic nanocomposite has been prepared by synthesizing and intercalating a new cationic aluminum-hydroxy ferric ferrocyanide compound into a cation-adsorbing nanoclay (montmorillonite). Chemical and structural properties were investigated by X-ray diffraction, transmission electron microscopy, thermogravimetric and differential thermal analyses, Fourier transform infrared, X-ray photoemission, and Mössbauer spectroscopies. Elemental analysis was based on proton-induced gamma ray emission and X-ray fluorescence spectroscopy data, N/C elemental ratios, and cation-exchange capacity measurements. Magnetic properties were studied by SQUID magnetometry. The results suggest: (i) that the cationic Prussian blue analog comprises Al-hydroxy cations embedded into a monolayer thick two-dimensional ferric ferrocyanide array; and (ii) that the clay-Prussian blue nanohybrid consists of such arrays stacked between the clay layers. The latter material orders ferromagnetically at ∼5K showing a hundred times higher remanence than that of the starting material, soluble Prussian blue (ammonium ferric ferrocyanide). [Copyright &y& Elsevier]

A water soluble cationic metal complex (tris(2,2'-bipyridine)ruthenium(II)) can be loaded into hydrogels containing acrylamide and/or acrylic acid units. The cationic complex is retained in polymer containing acrylic acid units at high pH and released at low pH. This is likely due to electrostatic interactions of the cation with the carboxylate anions, present at high pH, which are converted into neutral carboxylic acid at low pH, releasing the metal complex. Since the gel contract at low pH, the water soluble cation is also released with the water expelled from the gel. However, a strong retention of the cation inside the gels is observed when acrylamide units are present. A possible explanation is a hydrophobic interaction of the large metal complex with the polyacrylamide network. Using the counteracting electrostatic and hydrophobic interactions of probe molecules with smart hydrogel matrixes it is possible to tune the pH of maximum release away from the pKa of the ionizable group. [ABSTRACT FROM AUTHOR]

Abstract: Cationic palladium(II) and rhodium(I) complexes bearing 1,2-diaryl-3,4-bis[(2,4,6-tri-t-butylphenyl)phosphinidene]cyclobutene ligands (DPCB–Y) were prepared and their structures and catalytic activity were examined (aryl=phenyl (DPCB), 4-methoxyphenyl (DPCB–OMe), 4-(trifluoromethyl)phenyl (DPCB–CF3)). The palladium complexes [Pd(MeCN)2(DPCB–Y)]X2 (X=OTf, BF4, BAr4 (Ar=3,5-bis(trifluoromethyl)phenyl)) were prepared by the reactions of DPCB–Y with [Pd(MeCN)4]X2, which were generated from Pd(OAc)2 and HX in MeCN. On the other hand, the rhodium complexes [Rh(MeCN)2(DPCB–Y)]OTf were prepared by the treatment of [Rh(μ-Cl)(cyclooctene)2]2 with DPCB–Y in CH2Cl2, followed by treatment with AgOTf in the presence of MeCN. The cationic complexes catalyzed conjugate addition of benzyl carbamate to α,β-unsaturated ketones. [Copyright &y& Elsevier]

Starting from the [PtCl(η1-C2H4OMe)(phen)] (phen = 1,10-phenanthroline, 1) platinum(II) precursor, we synthesized and characterized by multinuclear NMR new [Pt(η1-C2H4OMe)(L)(phen)]+ (L = NH3, 2; DMSO, 3) complexes. These organometallic species, potentially able to interact with cell membrane organic cation transporters (OCT), violating some of the classical rules for antitumor activity of cisplatin analogues, were evaluated for their cytotoxicity. Interestingly, despite both complexes 2 and 3 resulting in greater cell uptake than cisplatin in selected tumor cell lines, only 3 showed comparable or higher antitumor activity. General low cytotoxicity of complex 2 in the tested cell lines (SH-SY5Y, SK-OV-3, Hep-G2, Caco-2, HeLa, MCF-7, MG-63, ZL-65) appeared to depend on its stability towards solvolysis in neutral water, as assessed by NMR monitoring. Differently, the [Pt(η1-C2H4OMe)(DMSO)(phen)]+ (3) complex was easily hydrolyzed in neutral water, resulting in a comparable or higher cytotoxicity in cancer cells with respect to cisplatin. Further, both IC50 values and the uptake profiles of the active complex appeared quite different in the used cell lines, suggesting the occurrence of diversified biological effects. Nevertheless, further studies on the metabolism of complex 3 should be performed before planning its possible use in tissue- and tumor-specific drug design. [ABSTRACT FROM AUTHOR]