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Two Cd(II) coordination compounds exhibit tunable excitation-dependent emissions in the solid state originating from a combination of exciplex and charge-transfer complexes. Two Cd(II) coordination compounds, i.e. [Cd(HL)(phen) 2 (H 2 O)]·HL·3H 2 O (1) and {[Cd(HMeL) 2 (4,4′-bipy)(H 2 O)]·H 2 O} n (2) and (where HL = N -carboxymethyl- N -phenyliminoacetato, HMeL = N -carboxymethyl- N -(m -methylphenyl)iminoacetato, 4,4′-bipy = 4,4′-bipyridine and phen = phenanthroline) have been synthesized and characterized by elemental analysis, IR and single-crystal X-ray diffraction methods. The photoluminescence properties and mechanisms, studied by means of solid state absorption, excitation/emission spectra, time-resolved lifetime techniques, and density functional theory (DFT) calculations, indicate that the emissions of both compounds originate from a combination of exciplex and charge-transfer complex. Interestingly, both compounds exhibit excitation-dependent emissions, which can be used to fine-tune their emission wavelengths. [ABSTRACT FROM AUTHOR]

A new polyiodide compound [Ni(bpy) 3 (H 2 O) 2 ]·bpy·2H 2 O·2I 3 − with the rare 1D → 3D interdigitated architecture has been synthesized by hydrothermal method. A new polyiodide compound [Ni(bpy) 3 (H 2 O) 2 ]·bpy·2H 2 O·2I 3 − (1), where bpy is 4,4′-bipyridine, has been synthesized by hydrothermal method. In 1 , the adjacent Ni(II) ions are bridged with the bpy ligand to form a 1D chain, which is further extended to be a 3D supramolecular framework by π – π interactions. This 3D supramolecular framework is a rare 1D → 3D interdigitated architecture. Compound 1 has been characterized by X-ray crystallography, elemental analysis, IR, PXRD and TG. The variable-temperature magnetic studies indicate very weak antiferromagnetic interactions in 1. [ABSTRACT FROM AUTHOR]

Graphical abstract Two new coordination compounds {[Cu(L 1)]·(ClO 4)·2H 2 O} (1) and [Cu 2 (L 2) 2 ]·(ClO 4) 2 (2) were synthesized with novel tripodal ligands N1-(2-Amino-ethyl)-N1-(1H-imidazol-2-ylmethyl)-ethane-1,2-diamine (HL 1) and N1-(2-Amino-ethyl)-N1-(2H-pyrazol-3-ylmethyl)-ethane-1,2-diamine (HL 2). 1 exhibits 1D zig-zag chain structure and 2 displays dinuclear structure, and both of them exhibit antiferromagnetic interactions between the Cu(II) atoms. Abstract Two new coordination compounds {[Cu(L 1)]·(ClO 4)·2H 2 O} (1) and [Cu 2 (L 2) 2 ]·(ClO 4) 2 (2) were synthesized with novel tripodal ligands N1-(2-Amino-ethyl)-N1-(1H-imidazol-2-ylmethyl)-ethane-1,2-diamine (HL 1) and N1-(2-Amino-ethyl)-N1-(2H-pyrazol-3-ylmethyl)-ethane-1,2-diamine (HL 2), respectively. Interestingly, coordination compound 1 exhibits one-dimensional (1D) zig-zag chain structure, coordination compound 2 displays dinuclear structure. The results showed that nitrogen-position of the ligands have distinct impact on the frameworks of the coordination compounds. In addition, the magnetic studies indicated that 1 and 2 exhibit antiferromagnetic interactions between the Cu(II) atoms. [ABSTRACT FROM AUTHOR]

The synthesis, characterization, DFT and, in two cases, the structure of seven novel dichloro(bis{2-[1-(4-methylphenyl)-1H-1,2,3-triazol-4-yl-κN 3 ]pyridine-κN})metal(II) coordination compounds ([M(L 2 ) 2 Cl 2 ]), containing transition metals of groups 7–12, are described. Both experimentally measured magnetic moment and DFT calculations showed that d 5 Mn(II) (with µ eff  = 5.62 B.M., S  = 5/2), d 6 Fe(II) (with µ eff  = 5.26 B.M., S  = 2), d 7 Co(II) (with µ eff  = 3.98 B.M., S  = 3/2), d 8 Ni(II) (with µ eff  = 3.00 B.M., S  = 1) and d 9 Cu(II) (with µ eff  = 1.70 B.M., S  = ½) are all paramagnetic, while d 10 Zn(II) and Cd(II) are diamagnetic with S  = 0. DFT calculations on the possible isomers of these coordination compounds, showed that the cis–cis – trans and the trans – trans – trans isomers, with the pyridyl groups trans to each other, are the lowest in energy. The trans – trans – trans isomers were experimentally characterized by X-ray crystallography for [Ni(L 2 ) 2 Cl 2 ] and [Zn(L 2 ) 2 Cl 2 ]·L 2 in this study. In the solid state the coordination compounds are connected by intermolecular hydrogen bonds, mainly involving the chloride atoms, to form 3D supramolecular structures. Computational chemistry calculations, using Natural Bonding Orbital calculations, identified these inter-molecular hydrogen bonds, C H⋯Cl, by a donor–acceptor interaction from a filled lone pair NBO on Cl to an empty antibonding NBO on (C H). The inter-molecular hydrogen bonds were also identified by QTAIM determined bonding paths between Cl and the respective hydrogen. The theoretically calculated computational chemistry results thus give an understanding on a molecular level why in the solid state where inter-molecular forces and packing play a role, the trans – trans – trans isomers are mostly obtained. [ABSTRACT FROM AUTHOR]

New silver complexes [AgL(NO 3 )] n ( 1 ), [AgL 2 (NO 3 )] n ( 2 ) and [AgL 3 (NO 3 )] 2 ( 3 ) (L = 4-amino-2,1,3-benzothiadiazole) were obtained as single-phase products of the reactions of AgNO 3 with L by varying their ratio. The structures of 1 – 3 were established by single-crystal X-ray diffraction and contain {Ag 2 L 2 } units, where L acts as a bridging ligand. The other metal coordination sites are occupied by O atoms of nitrates and N atoms of L ligands. Several types of strong and weak L–L and Ag–L interactions in the complexes are discussed herein, supported by quantum chemical calculations. Differences in the structures of the complexes cause significant changes of the photoluminescence intensity: no emission for 2 and noticeable for 1 and 3 . However, similar values of luminescence maxima for 1 and 3 (630 and 620 nm, respectively) result in red emission for both compounds. Structural, topological, and spectroscopic findings are interpreted on the basis of state-of-the-art quantum mechanical calculations. [ABSTRACT FROM AUTHOR]

Three coordination compounds, zero-dimensional Co(tib)(ADC) 2 ( BUC-60 ), one-dimensional Zn 3 (tib) 2 Cl 6 ( BUC-61 ) and three-dimensional [Cu 2 (tib) 2 (MoO 4 )Cl]Cl ( BUC-62 ), were obtained from the reaction of 1,3,5-tris(1-imidazolyl)benzene (tib), 1,3-adamantanedicarboxylic acid (H 2 adc), phosphomolybdic acid hydrate (H 3 PO 4 ·12MoO 3 ) and the corresponding metal salts under hydrothermal conditions. The as-prepared samples were characterized by single-crystal X-ray diffraction, Fourier transform infrared spectroscopy, CHN elemental analyses, thermal gravity analyses and photoluminescence spectroscopy. BUC-60 and BUC-61 exhibit good adsorption performances toward congo red ( CR ) and mordant blue 13 ( MB13 ). The maximum adsorption capacities of BUC-60 and BUC-61 toward CR are 1949 and 1992 mg g −1 , respectively, along with those toward MB13 being 564 and 209 mg g −1 , respectively. In addition, BUC-60 can selectively capture anionic dyes molecules from a dye matrix. [ABSTRACT FROM AUTHOR]

4-Amino-2,1,3-benzothiadiazole (L) and its model complexes with Cu + , Zn 2+ , Ag + and Cd 2+ have been computationally investigated in order to reveal the origins of coordination preferences of this multidentate ligand. The computational description is consistent with the analysis of experimental crystal structures of the coordination compounds described earlier and of two new complexes viz . [ZnL(H 2 O)Cl 2 ] and [CdL 2 (H 2 O) 2 (NO 3 ) 2 ]. Possible coordination types of L are discussed by means of rotational hindrance of NH 2 group, relative thermodynamic stability of the complexes and intramolecular interaction analysis. On the basis of our findings, molecular structure – spectral properties relationships of the complexes are revealed. The results obtained for L are compared with those obtained for 8-aminoquinoline, which is structurally similar to L and is known to form a number of metal complexes. [ABSTRACT FROM AUTHOR]

Complexes [Pd(aemptrz)Cl 2 ] ( 1 ) and [Pd 2 (μ-mptrz) 2 (mptrz) 2 (en)]·CH 3 OH ( 2 ) (where aemptrz is 1‐(1‐(λ 2 ‐azanyl)ethyl)‐4‐methyl‐5‐(λ 1 ‐sulfanyl)‐4 H ‐1λ 4 ,2,4‐triazole, mptrz is 4-methyl-4 H -1,2,4-triazole-3-thiolato and en is ethylene diamine) were synthesized by the reaction of 4-methyl-4 H -1,2,4-triazole-3-thiol (Hmptrz) ( 1 ) or a mixture of (Hmptrz) and ethylene diamine ( 2 ) with PdCl 2 . Complexes [Pd 2 (μ-mptrz) 4 ] ( 3 ) and [Pd 2 (μ-mptrz) 2 (mptrz) 2 (en)] ( 4 ) were obtained by similar methods, but using Pd(OAc) 2 instead of PdCl 2 . The four complexes were thoroughly characterized by elemental analysis, IR, UV–Vis, 1 H NMR, luminescence spectroscopy as well as single-crystal X-ray diffraction method. Central Pd(II) ions in 1 are tetra-coordinated by two chloride atom in the cis -positions, one sulfur atom and one nitrogen atom to form PdNSCl 2 coordination sphere, presenting slightly distorted square planar geometry around Pd atom. In complex 2 , the Pd1 atoms are coordinated to four triazole units via four Pd S bond (PdS 4 square-plane) and the Pd2 atoms are coordinated to two of these triazole units together with the two N atoms of ethylene diamine ligand (PdN 4 square-plane). In complex 3 the two Pd(II) centers are connected together by four bridging triazole ligands providing a paddle wheel-like arrangement. The Pd1 atom in complex 4 has a square-planar coordination involving the S atoms from four mptrz − ligands (two terminals and two bridged triazole) and the Pd2 atom is coordinated by two nitrogens of ethylene diamine and two nitrogens of the two bridged triazole ligand. Complex 1 has τ 4 value (the geometric parameter) of 0.043, which fits with a slightly distorted square planar geometry. Considering the Pd⋯Pd contact, the stereochemistry of the palladium(II) ion in 2 , 3 and 4 suggest a distorted square pyramid with a geometrical factor τ 5 = 0.042, 0.013 and 0.040, respectively. The luminescence properties of the free ligand as well as the complexes 1 – 4 were investigated in solution. [ABSTRACT FROM AUTHOR]

Four new tetranuclear complexes, [Ln 4 (dbm) 4 (O-btd) 6 (OH) 2 ] 1a (Ln = Yb), 1b (Ln = Dy) and [Ln 4 (dbm) 6 (O-btd) 4 (OH) 2 ] 2a (Ln = Yb), 2b (Ln = Dy) (O-btd = 4-hydroxo-2,1,3-benzothiadiazolate and dbm = dibenzoylmethanide), and their solvates with toluene and tetrahydrofuran were synthesized. The magnetic properties of the complexes 1a , 1b , 2a and 2b have been studied, revealing different magnetic susceptibility patterns for the Yb(III) and Dy(III) complexes in the temperature range 80–300 K. Upon lowering the temperature, a weak antiferromagnetic ordering is observed for both Yb compounds, while the Dy derivatives are assumed to show weak ferromagnetic interactions. The Yb complexes 1a and 2a demonstrate strong NIR luminescence at ∼1000 nm in CH 2 Cl 2 solution upon excitation of the (O-btd) − ligand. This observation suggests the (O-btd) − ligand to be an efficient antenna ligand for lanthanide-based NIR luminescence. [ABSTRACT FROM AUTHOR]

Five new coordination compounds, [Ag 2 (L3) 2 ]·(ClO 4 ) 2 ( 1 ), [Zn(L3)(Cl)]·(ClO 4 )·H 2 O ( 2 ) [Zn 2 (L3)(Cl) 4 ] ( 3 ), [Cu(L3)(Cl)]·(Cl)·2H 2 O ( 4 ) and [Cd(L3)(Cl)(H 2 O)]·(ClO 4 )·H 2 O ( 5 ), with the tripodal ligand N 1 -(2-amino-ethyl)-N 1 -pyridin-3-ylmethyl-ethane- 1,2-diamine (L3) have been synthesized. Interestingly, coordination compound 1 shows a dinuclear structure, coordination compounds 2 , 4 and 5 display 1D zig-zag chain structures, and coordination compound 3 exhibits an uncommon 1D chain structure. The results showed that the metal ions and anions have a distinct impact on the frameworks of the coordination compounds. The photoluminescent properties of the ligand and coordination compounds were also investigated. [ABSTRACT FROM AUTHOR]

Nine coordination compounds, namely, Cu(Hdmpz) 2 (L1) 2 ( 1 ) (Hdmpz = 3,5-dimethylpyrazole, L1 = 4-methylbenzoate), Cu(Hdmpz) 2 (L2) 2 ( 2 ) (L2 = 3-methylbenzoate), Cu(Hdmpz) 2 (L3) 2 ( 3 ) (L3 = 2-chlorobenzoate), Cu(Hdmpz) 2 (L4) 2 ( 4 ) (L4 = 2-chloronicotinate), Cu(Hdmpz) 2 (L5) 2 ( 5 ) (L5 = 4-methoxybenzoate), Cu(Hdmpz) 2 (L6) 2 ( 6 ) (L6 = 1-naphthylacetate), Cu 2 (Hdmpz) 4 (L7) 2 ( 7 ) (L7 = 1,4-cyclohexanedicarboxylate), Cu(Hdmpz) 2 (L8) ( 8 ) (L8 = terephthalate) and Cu 3 (Hdmpz) 9 (L9) 2 ·Hdmpz ( 9 ) (L9 = trimesate) have been synthesized by the self-assembly of copper acetate, 3,5-dimethylpyrazole and carboxylate ligands at room temperature. All the compounds were structurally characterized by different techniques, including elemental analysis, IR spectra, TG and single crystal X-ray diffraction analysis. The X-ray studies suggested that these complexes display mononuclear to trinuclear structures with tetrahedral (for compounds 1 – 8 ) or distorted square pyramidal (for compound 9 ) geometries around the copper ion. The pyrazole and carboxylate groups in all the compounds are only coordinated in the monodentate fashion. The uncoordinated oxygen atom of the carboxylate groups in all of the compounds forms intramolecular/intermolecular hydrogen bonding with the N–H group of the coordinated 3,5-dimethylpyrazole. On the basis of the X-ray crystallographic study, the rich intra- and intermolecular N–H⋯O hydrogen bonds, and other weak interactions, including CH 3 –C π , Cl⋯O, C–H⋯O, CH 3 ⋯O, C–H⋯π, CH 3 –π, and π–π associations, are analyzed. The various non-bonding interactions in these compounds are responsible for different structures such as sheet, 3D network and 3D layer structures. The thermal stabilities for 1 – 9 were examined and the results show that the complexes seem to be good candidates for novel inorganic–organic hybrid materials with good thermal stability. [ABSTRACT FROM AUTHOR]

Stoichiometry, steric factors, and hydrogen bonding directly influence the bonding behavior of hydrazine and its derivatives with RuCl 2 (PPh 3) 3. [Display omitted] The reactivity of the prominent ruthenium(II) catalyst and precursor, RuCl 2 (PPh 3) 3 , was explored with hydrazine and its derivatives. The reactions produced 6-coordinate ruthenium(II) products that bond with the hydrazine moiety in bridging (NH 2 NH 2 or NH 2 NHMe), end-on (NH 2 NHMe, NH 2 NHPh, or NH 2 NMe 2), or side-on (NH 2 NMe 2) fashions. The products have been characterized by single crystal X-ray diffraction and 31P NMR spectroscopy. With NH 2 NH 2 , the dimeric product, [RuCl 2 (PPh 3) 2 ] 2 (μ -N 2 H 4) 2 , was formed under all conditions used. For other hydrazines, the reaction stoichiometry governed product formation to yield either bimetallic or monomeric products. When the RuCl 2 (PPh 3) 3 to hydrazine derivative ratio was 1:1 or lower, bimetallic complexes were formed while a 1:2 ratio produced monomeric compounds. The exception to the latter occurs with the production of the monomeric compound, RuCl 2 (PPh 3) 2 (η 2-NH 2 NMe 2), that forms employing a 1:1 ratio. In addition to stoichiometry, steric factors and hydrogen bonding played a significant role in dictating the bonding mode of hydrazines. The bimetallic complexes were further reacted to yield the corresponding monomeric products, adopting the form RuCl 2 (PPh 3) 2 (L) 2 (L = NH 2 NHMe, NH 2 NHPh, or NH 2 NMe 2). Reactions utilizing less than a 1:2 ratio of RuCl 2 (PPh 3) 3 to NH 2 NMe 2 produced a mixture of products that appear to be in equilibrium. DFT calculations were performed to gain insight into the reaction energetics and molecular stability. [ABSTRACT FROM AUTHOR]

Abstract: Two heteronuclear NCS-bridged compounds, namely [{Cu(3,3,3-tet)(CH3CN)}2{Mo(NCS)6}][Mo(NCS)6][PPh4]2·6CH3CN (1) and [{Cu(3,3,3-tet)(CH3CN)}4{Mo(NCS)6}][Mo(NCS)6]3[Cu(3,3,3-tet)(CH3CN)]2 (2) (with 3,3,3-tet= N,N-bis(3-aminopropyl)-1,3-propanediamine) have been synthesized and their crystal structures were characterized by single crystal X-ray diffraction studies. For the cationic trinuclear cluster of 1 one hexaisothiocynato Mo(III) unit, [Mo(NCS)6]3−, is linked to two Cu units through two NCS bridging ligands, and the anionic pentanuclear cluster of 2 results from the linkage of the Mo unit to four Cu moieties. In 1 and 2, the coordination of a solvent molecule (i.e. acetonitrile) in one apical position of Cu prevents the extension of the system, while charge neutrality is achieved by co-crystallization of non-bonded Cu and/or Mo complexes. Magnetic studies of 1 and 2 reveal the weak antiferromagnetic interaction between the two spin carriers CuII and MoIII, through the NSC ligand. For 1, modeling the experimental data yields a value of J MoCu =−5.9cm−1 (H =−J(S1 S2 + S2 S3 )) for the exchange interaction. [Copyright &y& Elsevier]

Abstract: In this paper a pyridine-based racemic ligand [N,N′-bis(2-pyridylmethylidene)-1,2-(R,R + S,S)-cyclohexanediamine], 1, and its new trifluoromethansulfonate (CF3SO3 −, triflate) and nitrate Eu(III) complexes were studied, both in the solid state and in acetonitrile (AN) solution. In the case of the triflate complexes, a combination of structural and spectroscopic evidences, revealed the different nature of the species in solution and in the solid state. On the contrary, the nitrate adduct in the solid state presented similar features as the complex present in AN solution. All triflate and nitrate complexes detected in solution are highly stable. [Copyright &y& Elsevier]

Treatment of metal(II) halides (metal = Cu, Ni, Co, Fe, Mn, Cr) with the potassium salts of carbohydrazides L1–L6 afforded Cu(L1)2 (75%), Cu(L2)2 (51%), Cu(L3)2 (23%), Co(L1)2 (57%), Cr(L1)2 (62%), Ni(L1)2 (76%), Ni(L2)2 (62%), Ni(L3)2 (62%), Ni(L4)2 (13%), Ni(L5)2 (11%), Ni(L6)2 (29%), [Fe(L1)2]2 (28%), and [Mn(L1)2]2 (12%) as crystalline solids, where L1 = Me2NNC(tBu)O−, L2 = Me2NNC(iPr)O−, L3 = Me2NNC(Me)O−, L4 = (CH2)5NNC(tBu)O−, L5 = (CH2)5NNC(iPr)O−, and L6 = (CH2)5NNC(Me)O−. These complexes were characterized by spectral and analytical techniques, and by X-ray crystal structure determinations for Cu(L1)2, Co(L1)2, Cr(L1)2, Ni(L1)2, and [Fe(L1)2]2. Cu(L1)2, Co(L1)2, Cr(L1)2, and Ni(L1)2 exist as square planar, monomeric complexes, whereas [Fe(L1)2]2 is a dimer. A combination of sublimation studies, thermal decomposition temperature determinations, and thermogravimetric/differential thermal analysis demonstrate that the Cu, Co, and Ni complexes Cu(L1)2, Cu(L2)2, Co(L1)2, Ni(L1)2, and Ni(L2)2 have the lowest sublimation temperatures and highest decomposition temperatures among the series. Additionally, these compounds have higher volatilities and thermal stabilities than commonly used ALD and CVD precursors. Hence, these new complexes have excellent properties for application as ALD precursors to Cu, Co, and Ni metal films. [Copyright &y& Elsevier]

The reaction of the potassium diketiminate K[RN＝C(CF3)CH＝(CF3)CNR)], where R = 3,5-C6H3Me2, with PPh3AuCl afford the complex [RN＝C(CF3)CH＝(CF3)CNR)AuPPh3]. Unlike gold(I) diketiminates without backbone-CF3 substituents, the complex is thermally stable in the solid state and in solution. The crystal structure confirms that, unlike previous examples of Au(I) ketiminates, this complex possesses a three-coordinate metal centre with a distorted Y-shaped coordination geometry. [Copyright &y& Elsevier]

Abstract: The solvent-mediated crystal-to-crystal transformation was observed from yellow crystal of NiCl2(CH3OH)2(1,4-dioxane)0.5 (1) to green crystal of [NiCl2(H2O)2(1,4-dioxane)](1,4-dioxane) (2) under high humidity or adding of H2O in CH3OH/1,4-dioxane solution. The μ-Cl2 bridge in 1 replaced by 1,4-dioxane bridge in 2. In 1, the chlorine-bridged linear chains of NiCl2(CH3OH)2 and 1,4-dioxane molecules stack along the b- and c-axis alternatively with hydrogen bonds intrachain, interchain, between chain and solvent. These hydrogen bonds and dipolar interaction between ferromagnetic coupling chlorine-bridged chains result in long-range ferromagnetic ordering at 3.1K and a strong frequency dependence of the ac-susceptibilities associated to domain structures with very large shape anisotropy was observed below 3.1K. In 2, layers of 1,4-dioxane-bridged linear chains of NiCl2(H2O)2(1,4-dioxane) are intercalated by layer of 1,4-dioxane molecules with hydrogen bonds between chain and solvent. Compound 2 is paramagnet to 2K. [Copyright &y& Elsevier]

Abstract: This work presents a new oxovanadium(IV)–cucurbit[6]uril complex, which combines the catalytic properties of the metal ion with the size-excluding properties of the macrocycle cavity. In this coordination compound, the ions are coordinated to the oxygen atoms located at the rim of the macrocycle in slightly distorted square-pyramidal configurations, which are in fact symmetries. This combination results in a size-selective heterogeneous catalyst, which is able to oxidize linear alkanes like n-pentane at room temperature, but not styrene, cyclohexane or z-cyclooctene, which are too big to enter the cucurbit[6]uril cavity. The results presented here contribute to understanding the mechanism of alkane catalytic oxidation by oxovanadium(IV) complexes. [ABSTRACT FROM AUTHOR]

[Display omitted] Bis-tridentate chelates of Zn(ClO 4) 2 , Cd(ClO 4) 2 , and Hg(ClO 4) 2 with two equivalents of bis(2-pyridylmethyl) ether (L1) were isolated. The complexes were characterized using X-ray crystallography, IR, 1H NMR, and TGA. Isomorphs [Zn(L1) 2 ](ClO 4) 2 ·CH 3 CN (1 ·CH 3 CN) and [Cd(L1) 2 ](ClO 4) 2 ·CH 3 CN (2 ·CH 3 CN) crystallized in the monoclinic space group P 2 1 with meridional octahedral geometry. [Hg(L1) 2 ](ClO 4) 2 (3) crystallized in the monoclinic space group P 2 1 / c with approximately C 2 symmetric trigonal prismatic geometry. Proton NMR of 3 at −40 °C revealed heteronuclear J HgH coupling yet lacked the geminal splitting of methylene protons expected from the solid-state structure suggesting equivalence through intramolecular reorganization was rapid relative to the NMR time scale. The complexes are compared to other bis-tridentate chelates of bis(2-pyridylmethyl) ligands with the central oxygen of L1 replaced by other heteroatoms. [ABSTRACT FROM AUTHOR]

The reaction of Ti(bipy)3 with BF3 resulted in the formation of [Ti(bipy)3]BF4 (1), whereas the interaction of Ti(bipy)3 with the LiAlH4 yielded the unforeseen aluminum complex Li(THF)4[Al(bipy)2] (2). The complexes 1 and 2 were characterized by NMR, mass spectra and elemental analysis. Complex 2 was investigated by X-ray structural analysis and consists of cationic [Li(THF)4]+ and anionic [Al(bipy)2]− units containing the coordinated dinegatively charged [bipy] ligand. [Copyright &y& Elsevier]

Single crystal X-ray diffraction shows that [La(gly)2(H2O)2(phen)2(CH3CH2OH)](ClO4)3(phen)3·3H2O (1), [Ln(gly)2(H2O)2(phen)2](ClO4)3 (phen)4·nH2O [n=0, Ln=Nd (2); n=1, Ln=Ho (3)], and [Yb(gly)4(H2O)(phen)](ClO4)4(phen)2(gly+H)·2H2O (4) (gly=glycine, phen=1,10-phenanthroline) with the coordination number 9 for La3+, 8 for Nd3+ and Ho3+, and 7 for Yb3+, exhibit the effect of lanthanide contraction. Complexes 1–4 are all mononuclear structures, with the ligand glycine coordinated to the Ln3+ ion in the monodentate mode and in zwitterionic form. There exist free phen molecules and solvent molecules in the lattice. Therefore, there are different types of hydrogen bonding and π–π stacking interactions in the crystals that give rise to different supramolecular architectures. The structure of 1 is composed of 1D chains which extend in the [1 0 0] direction, while those of 2 and 3 are 2D structures extending in the (0 0 1) plane. However, complex 4 shows a complicated 3D network. [Copyright &y& Elsevier]

Isoquinoline-containing bidentate chelators with varying 1- and 3-connectivity prepared from tandem CuAAC methods are capable of forming stable 3:1 Ru(II) coordination compounds. Isoquinoline connectivity influences the spectroscopic properties of these complexes, while isoquinoline incorporation can significantly improve antibacterial properties relative to analogous complexes with pyridine-containing chelators. Bidentate chelators 1-(1-benzyl-1,2,3-triazol-4-yl)isoquinoline and 3-(1-benzyl-1,2,3-triazol-4-yl)isoquinoline were prepared from benzyl bromide and trimethylsilylethynylisoquinoline precursors using a tandem deprotection/substitution/CuAAC synthetic approach. Each chelator is capable of forming a stable 3:1 Ru(II) coordination compound, which forms as a geometric isomer mixture. These Ru(II) complexes possess unique MLCT absorbance signatures at 450/472 nm (1-isomer) and 367 nm (3-isomer) relative to their constituent chelating units. Minimum inhibitory concentration values as low as 0.4 μM are observed for Ru(II) complexes against representative Gram-positive bacteria Bacillus subtilis and Staphylococcus epidermidis. Comparing the MIC values of these isoquinoline compounds with analogous 2-(1-benzyl-1,2,3-triazol-4-yl)pyridine compounds shows a 2.5- to 40-fold improvement in potency. This study establishes that increased hydrophobicity introduced at the central chelating units of Ru(II) coordination compounds can be a useful means by which to optimize antimicrobial activity that is complimentary to the variation of peripheral substituent identity at the chelator's N1 triazole position. [ABSTRACT FROM AUTHOR]