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Three new heteroleptic Ag(I) complexes, labeled as [AgL(POP)]BF4 (1–3), were successfully synthesized and comprehensively characterized. Here, L represents 2,9-bis((E)-4-methoxystyryl)-1,10-phenanthroline (L1), 2,9-bis((E)-4-methylthiostyryl) -1,10-phenanthroline (L2), and 2,9-bis((E)-4-diethylaminostyryl)-1,10-phenanthroline (L3), while POP stands for Bis[(2-diphenylphosphino)phenyl] ether. The stability of these compounds in solution was confirmed through multinuclear 1D (1H, 13C, 31P) and 2D NMR (COSY, NOESY, HMBC, HSQC) spectroscopies. Additionally, their molecular structure was elucidated via X-ray crystallography. The photophysical properties of the complexes were assessed both in the solid state and in solution (dichloromethane). Compounds 1–3 demonstrated moderate emissions in solution, with quantum yields ranging from 11–23%. Interestingly, their solid-state luminescent behavior differed. Large bathochromic shifts (42–75 nm) of the emission maxima and a decrease in quantum yields (2.5–9.5%) were evident, possibly due to the presence of excimers. Compound 3 stands out as a rare example of an Ag(I) red-color emitter. [ABSTRACT FROM AUTHOR]

Novel full-sandwich (η5-Cp)-Ru-paraphenylene complexes with the general formula [(η5-Cp)nRu(η6-L)](PF6)n where n = 1–3 and L = biphenyl, p-terphenyl and p-quaterphenyl, were synthesized and characterized by means of spectroscopic and analytical techniques. The structures of the complexes [(η5-Cp)Ru(η6-biphenyl)](PF6) (1), [(η5-Cp)Ru(η6-terphenyl)](PF6) (3) and [(η5-Cp)2Ru(η6-terphenyl)](PF6)2 (4) was determined by X-ray single crystal methods. The interaction of the complexes [(η5-Cp)Ru(η6-quaterphenyl)]Cl, (6)Cl, and [(η5-Cp)2Ru(η6-quaterphenyl)]Cl2, (7)Cl2, with the DNA duplex d(5′-CGCGAATTCGCG-3′)2 was studied using NMR techniques. The results showed that both complexes interacted non-specifically with both the minor and major grooves of the helix. Specifically, (6)Cl exhibited partial binding through intercalation between the T7 and T8 bases of the sequence without disrupting the C–G and A–T hydrogen bonds. Fluorometric determination of the complexes' binding constants revealed a significant influence of the number of connected phenyl rings in the paraphenylene ligand (L) on the binding affinity of their complexes with the d(5′-CGCGAATTCGCG-3′)2. The complexes (6)Cl and (7)Cl2 were found to be highly cytotoxic against the A549 lung cancer cell line, with complex (6) being more effective than (7) (IC50 for (6)Cl: 17.45 ± 2.1 μΜ, IC50 for (7)Cl2: 65.83 ± 1.8 μΜ) and with a selectivity index (SI) (SI for (6)Cl: 1.1 and SI for (7)Cl2: 4.8). [ABSTRACT FROM AUTHOR]

A novel heteroleptic Ag(I) compound, formulated as [AgL(PPh3)]BF4 (1) (where L represents 2,9-bis((E)-4-methoxystyryl)-1,10-phenanthroline and PPh3 stands for triphenylphosphine), was successfully synthesized and thoroughly characterized. The compound's stability in solution was confirmed through 1D and 2D nuclear magnetic resonance (NMR). The photo-irradiation of the complex in a CDCl3 solution, utilizing a common portable UV lamp emitting at λ = 365 nm, led to the partial transformation of the E,E-geometric isomer to E,Z, ultimately yielding a 1:1.4 molar ratio of isomers. Its molecular structure was determined via X-ray crystallography, while molecular packing was assessed using Hirshfeld calculations. The most notable interactions (51%) within the cationic inner sphere involved H···H bonds. The photophysical characteristics of the complex and L were evaluated both in the solid state and in solution (dichloromethane). Compound 1 is a weak emitter, with photoluminescence quantum yields of 8.6% and 4.3% in solution and the solid state, respectively. [ABSTRACT FROM AUTHOR]

Palladium(II) complexes of the general formula [Pd(η3-C3H5)(L)](PF6), where L is 4,7-diphenyl-1,10-phenanthroline (1), 2,9-dimethyl-1,10-phenanthroline (2), 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (3), 5-methyl-1,10-phenanthroline (4), 3,4,7,8-tetramethyl-1,10-phenanthroline (5), and 2-(2′-pyridyl) quinoxaline (6), were synthesized and characterized using high-resolution ESI-MS, NMR techniques and, in the case of (6), single-crystal X-ray diffraction methods. In addition, their photophysical properties were investigated. Complexes (1)–(6) were emitted in the greenish-blue region, with those containing methyl-substituted phenanthrolines having the higher quantum yield (≈14%) in the solid state. [ABSTRACT FROM AUTHOR]

A new emissive heteroleptic Ag(I) complex formulated as [AgL(POP)][PF6] (L = 4,4′-bis (4-Fluorophenyl)-6,6′-dimethyl-2,2′-bipyridine, POP= bis (2-(diphenylphosphino) phenyl) ether) was synthesized and characterized in both the solid state (X-ray crystallography) and the solution. The compound is a yellow-green phosphor (λem = 528 nm), with moderate quantum efficiency (ΦPL = 25% in deaerated dichloromethane). [ABSTRACT FROM AUTHOR]

A new bis cyclometallated Ir(III) phosphor, [Ir(ppy)2L]PF6 (ppy = 2-phenylpyridine, L = 4,4′-bis(4-fluorophenyl)-6,6′-dimethyl-2,2′-bipyridine was prepared and structurally characterized in the solid state (X-ray diffraction) and solution (1 and 2D NMR spectroscopy). The compound exhibited yellow photoluminescence (λem = 562 nm). The quantum yield Φ was solvent-dependent (5% in acetonitrile and 19% in dichloromethane solutions, respectively). [ABSTRACT FROM AUTHOR]

The modification of the methyl group of 4′-(p-tolyl)-2,2′:6′,2″-terpyridine produced the novel unnatural amino acid 3-(4-([2,2′:6′,2″-terpyridin]-4′-yl)phenyl)-2-aminopropanoic acid (phet). Mononuclear heteroleptic ruthenium complexes of the general formulae [Ru(L1)(L2)](PF6)2 (L1 = 2-acetylamino-2-(4-[2,2′:6′,2″]terpyridine-4′-yl-benzyl)-malonic acid diethyl ester, (phem), 3-(4-([2,2′:6′,2″-terpyridin]-4′-yl)phenyl)-2-aminopropanoic acid, (phet), and L2 = 2,2′:6′,2″-terpyridine (tpy), 4′-phenyl-2,2′:6′,2″-terpyridine (ptpy), 4′-(p-tolyl)-2,2′:6′,2″-terpyridine (mptpy)), as well as the homoleptic [Ru(phem)2](PF6)2 and [Ru(phet)2](PF6)2, were synthesized and characterized by means of NMR spectroscopic techniques, elemental analysis, and high-resolution mass spectrometry. The photophysical properties of the synthesized complexes were also studied. [ABSTRACT FROM AUTHOR]

The novel binuclear η6-arene-Ru(II) complexes with the general formula {[(η6-cym)Ru(L)]2(μ-BL)}(PF6)4, and their corresponding water soluble {[(η6-cym)Ru(L)]2(μ-BL)}Cl4, where cym = p-cymene, L = 2,2′-bipyridine (bpy) and 1,10-phenanthroline (phen), BL = 4,4′-bipyridine (BL-1), 1,2-bis(4-pyridyl)ethane (BL-2) and 1,3-bis(4-pyridyl)propane (BL-3), were synthesized and characterized. The structure of {[(η6-cym)Ru(phen)]2(μ-BL-1)}(PF6)4 was determined by X-ray single crystal methods. The interaction of {[(η6-cym)Ru(phen)]2(μ-BL-i)}Cl4 (i = 1, 2, 3; (4), (5) and (6) correspondingly) with the DNA duplex d(5′-CGCGAATTCGCG-3′)2 was studied by means of NMR techniques and fluorescence titrations. The results show that complex (4) binds with a Kb = 12.133 × 103 M−1 through both intercalation and groove binding, while (5) and (6) are groove binders (Kb = 2.333 × 103 M−1 and Kb = 3.336 × 103 M−1 correspondingly). Comparison with the mononuclear complex [(η6-cym)Ru(phen)(py)]2+ reveals that it binds to the d(5′-CGCGAATTCGCG-3′)2 with a Kb value two orders of magnitude lower than (4) (Kb = 0.158 × 103 M−1), indicating that for the binuclear complexes both ruthenium moieties participate in the binding. The complexes were found to be cytotoxic against the A2780 and A2780 res. cancer cell line with a selectivity index (SI) in the range of 3.0–5.9. [ABSTRACT FROM AUTHOR]

Spectroscopy, cryoscopy and microanalyses enable the characterization of Gd(tmhd)3 complexes that form adducts with glyme ligands, where tmhd-H is 2,2,6,6-tetramethylheptane-3,5-dione. The length of the glyme exhibits a positive correlation with the thermal stability of these compounds, wherein the Gd ion is seven- or eight-coordinated prismatically or antiprismatically. The glymes serve as chelating and bridging ligands in these adducts.

Zirconium(IV) metal organic frameworks (MOFs) with low net connectivity and available intra-framework sorption sites constitute excellent sorbents for toxic anions. To expand this family of highly promising sorbents, it would be desired to develop new synthetic strategies aiming towards such materials. Here we show that the utilization of terephthalate ligands with small to medium size alkyl-amino functional groups comprises an effective approach towards microporous Zr4+ MOFs with 8-connected frameworks. The new MOFs were proved the most effective Se(IV) and Se(VI) sorbents ever reported, with exceptional sorption capacities (up to 272 mgSe(IV) g−1 and 290 mgSe(VI) g−1), reusability, rapid sorption kinetics (≤3 min) and capability to sorb efficiently these anions in a very wide pH range (1–10), even in the presence of various competitive anions. The MOFs also display highly efficient sorption capability for the particularly toxic SeCN−, with such property demonstrated for the first time for MOF materials. [ABSTRACT FROM AUTHOR]