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A new polyoxometalate-based inorganic–organic hybrid material, H5Ag(Bbi)1.5(Bbi)2[P2W18O62] (1) (Bbi = 1,1-(1,4-butanediyl)-bis(imidazole)), has been hydrothermally synthesized and characterized by single-crystal X-ray diffraction, elemental analyses, IR spectroscopy, and thermogravimetric analysis. In 1, adjacent [P2W18O62]6− (short for P2W18) anions are connected through Ag by equatorially positioned terminal oxygen atoms to generate a 1-D chain. Adjacent chains were further connected through Ag and two-coordinated Bbi ligands into a (6, 3)-layer, which are extended to 3-D supermolecule nets through H bonds. The photo- and electro-catalytic properties of 1 have been studied. [ABSTRACT FROM PUBLISHER]

In this study, an easily synthesized polydentate ligand N,N,N',N'-tetra(diphenylphosphinomethyl)-1,2-ethylenediamine (1) in combination with [Pd(CH)Cl] was found to be an active catalyst in copper-free Sonogashira reactions. Most substrates, including steric hindered phenyl bromides and heteroaryl bromides, could couple efficiently with terminal alkynes in the presence of low catalyst loading (0.1 mol%) and this catalytic system showed excellent functional group tolerance. The influence of water in this system was also preliminarily investigated via P NMR in situ; that is, appropriate water favors the reaction while excess hindered this reaction. Graphical Abstract: A simple ligand N,N,N',N'-tetra(diphenylphosphinomethyl)-1,2-ethylenediamine was employed in Sonogashira reaction with relatively low catalyst loading and isolated yield up to 99 % was obtained in the absence of copper or any other additives. This catalytic system performed high efficiency and excellent functional group tolerance.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The formation of linear aldehyde from isomerization-hydroformylation of 2-butene represents an important subject and current task in industry. Both high activity and excellent regioselectivity were achieved in the rhodium-catalyzed 2-butene isomerization-hydroformylation with 2,2′-bis(dipyrrolylphosphinooxy)-1,1′-(±)-binaphthyl ( 1) as ligand. Bulky phosphite with electron-withdrawing pyrrol groups dramatically improved the selectivity of linear product, and a good yield of 90.5% aldehydes was obtained with an excellent linear aldehyde regioselectivity of 95.3% under optimized condition. Graphical Abstract: Bulky phosphite with electron-withdrawing pyrrol groups dramatically improved the selective of linear product, and an excellent yield of 90.5% aldehydes with 95.3% regioselectivity of linear aldehyde was obtained in the Rh-catalyzed isomerization-hydroformylation of 2-butene in the presence of ligand 1.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Two novel metal–organic frameworks (MOFs) based on different tetradentate in situligands, CuI3(L1)2(L2)[PMoVI8VV4O40(VIVO)2]·2H2O (1) and [CuI2Cl2(L3)] (2) (L1= 1,4-bis(imidazol-1-ylmethyl)benzene, L2= 1,2,4,5-tetra(4-pyridyl)-benzene L3= a-1-hydroxy-e,e,e,e-1,2,4,5-tetra(4-pyridyl)cyclohexane) have been rationally hydrothermally synthesized and characterized by elemental analyses, IR spectroscopy, TG analyses, and single-crystal X-ray diffraction, respectively. Here, compound 1represents the first example that dehydrogenative coupling has been employed to yield a novel tetradentate coplanar dye molecule in POM-based MOFs. It also exhibits unique 3D MOFs with two topologies (4284)(4283101)(86)2and (4383)(4284)(446289)(4106183) due to different definitions of nodes. Compound 2shows a two-fold diagonal/diagonal inclined interpenetration based on CuIions and in situsynthesized ligands L3. Interestingly, reaction conditions play important roles in the domination of in situligands (L2and L3) from the same precursor bpp (bpp = 1,3-bis(4-pyridyl)propane). Additionally, electrochemical and photocatalysis properties of compound 1have also been minutely investigated. [ABSTRACT FROM AUTHOR]

A new ligand ITAP and its complex [Ru(dmb)2(ITAP)](ClO4)2 (ITAP = isatino [1,2-b]-1,4,8, 9-tetraazatriphenylene, dmb = 4,4'-dimethyl-2,2'-bipyridine) have been synthesized and characterized by elemental analysis, Fast atom bombardment mass spectra, Electrospray mass spectra, and 1H NMR. Thermal denaturation and absorption titration experiments show the complex binds to calf thymus DNA (CT-DNA) with moderate affinities. Viscosity measurements and thermal denaturation indicate that the DNA-binding mode could be intercalative interaction. The Ru(II) complex in the presence of plasmid pBR322 DNA has been found to promote the cleavage of plasmid pBR322 DNA from the supercoiled Form I to the open circular Form II upon irradiation. Mechanisms for DNA cleavage by the complex were also investigated. [ABSTRACT FROM AUTHOR]

Abstract: Three new organic–inorganic hybrid materials with 4,4′-bipy ligands and copper cations as linkers, [CuII(H2O)(4,4′-bipy)2][CuII(H2O)(4,4′-bpy)2]2H[CuIIP8Mo12O62H12]·5H2O (1), [CuI(4,4′-bipy)][CuII(4,4′-bipy)]2 (BW12O40)·(4,4′-bipy)·2H2O (2) and [CuI (4,4′-bipy)]3 (PMo12O40)·(pip)·2H2O (3) (pip=piperazine; 4,4′-bipy=4,4′-bipyridine), have been hydrothermally synthesized. The single X-ray structural analysis reveals that the structure of 1 is constructed from [Cu(H2O)(4,4′-bipy)2] complexes into a novel, three-dimensional supermolecular network with 1-D channels in which Cu[P4Mo6]2 dimer clusters reside. To the best of our knowledge, compound 1 is the first complex in which the [P4Mo6] clusters have been used as a non-coordinating anionic template for the construction of a novel, three-dimensional supermolecular network. Compound 2 is constructed from the six-supported [BW12O40]5− polyoxoanions and [CuI(4,4′-bipy)] and [CuII(4,4′-bipy)] groups into a novel, 3-D network. Compound 3 exhibits unusual 3-D supramolecular frameworks, which are constructed from tetrasupporting [PMo12O40]3− clusters and [CuI (4,4′-bipy) n ] coordination polymer chains. The electrochemical properties of 2 and 3 have been investigated in detail. [Copyright &y& Elsevier]

Abstract: A new inorganic–organic hybrid complex, Na2[{Ag10(NC5H4COO)8(H2O)6}(SiW12O40)] (1), has been successfully synthesized from [SiW12O40]4− anions, Ag+ ions and 1,3-bis(4-pyridyl)propane under hydrothermal conditions and characterized by elemental analyses, IR spectroscopy, TG analyses, and single-crystal X-ray diffraction. In complex 1, each [SiW12O40]4− anion connects with six Ag atoms and in turn each Ag atom links to three [SiW12O40]4− anions, leading to a (6,3) layer. Such (6,3) layers are arranged in parallel and further linked by [Ag(H2O)(NC5H4COOH)2]− fragments to generate a 3D framework. The most striking feature in this work is that 1,3-bis(4-pyridyl)propane converses to isonicotinic acid in the synthetic reaction of 1, which may be induced by the combined function of Ag+ ion and polyoxometalate. [Copyright &y& Elsevier]

Abstract: Two new ruthenium(II) polypyridyl complexes [Ru(dmb)2(Fpp)](ClO4)2 1 (Fpp=2-(3′,3′-difluoro-3,4-methylenedioxyphenyl)imidazo[4,5-f][1,10]phenanthroline, dmb=4,4′-dimethyl-2,2′-bipyridine) and [Ru(bpy)2(Fpp)](ClO4)2 2 (bpy=2,2′-bipyridine) have been synthesized and characterized by elemental analysis, FAB-MS, ES-MS, IR, 1H NMR and 13C NMR. The DNA-binding behaviors of these complexes were investigated by absorption spectroscopic titration, viscosity measurements, thermal denaturation and photocleavage. The mechanism studies of photocleavage reveal that singlet oxygen (1O2) and superoxide anion radical (O2 −) may play an important role in the photocleavage. The cytotoxicity of complexes 1 and 2 have been evaluated by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) method. [Copyright &y& Elsevier]

Abstract: Two new ligands, 3-(pyrazin-2-yl)-as-triazino[5,6-f]-5-methoxylisatin (dtmi), 3-(pyrazin-2-yl)-as-triazino[5,6-f]-5-nitroisatin (dtni) and their ruthenium(II) complexes [Ru(phen)2(dtmi)](ClO4)2 (1) and [Ru(phen)2(dtni)](ClO4)2 (2) have been prepared and characterized by elemental analysis, FAB-MS, ES-MS and 1H NMR. The DNA-binding behaviors of complexes have been studied by spectroscopic titration, viscosity measurements, thermal denaturation and circular dichromism (CD). The results indicate that the complexes 1 and 2 interact with calf thymus DNA (CT-DNA) by intercalative mode. The DNA-binding affinity of the complexes 2 is larger than that complex 1 does. [Copyright &y& Elsevier]

A novel and conveniently prepared diphosphine ligand 6 H -Dibenzo[ d , f -[1,3]diazepin-6-ylidene,5,7-dihydro-5,7-diphenylphosphanyl] (DADPP) combined with [Pd(C 3 H 5 )Cl] 2 affords an efficient catalytic system for Mizoroki–Heck cross-coupling of aryl halides with alkenes. The system could give the yield of 95% for 4-chloronitrobenzene with 0.05 mol.% [Pd(C 3 H 5 )Cl] 2 . For the bromide-substituted substrates, the highest turnover number (TON) is up to 96,000,000. [ABSTRACT FROM AUTHOR]

Rhodium-catalyzed hydroformylation of dicyclopentadiene using different kinds of mono- and bidentate phosphorus ligands was studied. The results demonstrated that the electronic and steric properties of ligand could influence the catalytic activity and the selectivity towards dialdehyde products. High conversion (99.9%) and good selectivity (95.0%) to dialdehydes were achieved under optimized reaction conditions in the presence of Rh/mixed mono- and bidentate phosphorus ligand complex (bidentate ligand: 2,2′-bis(dipyrrolylphosphinooxy)-1,1′-(±)-biphenyl (L1) and monodentate ligand: tri-(4-methoxylphenyl)phosphine (L8) (L1/L8 molar ratio 1/2)), which offers an easy approach to prepare dialdehydes from hydroformylation of cyclopentadiene under mild conditions (5.0MPa, 100°C). [ABSTRACT FROM AUTHOR]

Abstract: Six multidentate nitrogen ligands, 2,6-bis(1,5-diphenyl-1H-pyrazol-3-yl)pyridine (L1), 2,6-bis(1-methyl-5-phenyl-1H-pyrazol-3-yl)pyridine (L2), 2,6-bis(1,5-dimethyl-1H-pyrazol-3-yl)pyridine (L3), 2,6-bis(5-phenyl-1H-pyrazol-3-yl)pyridine (L4), 2,6-bis(1-p-triflurophenyl-5-phenyl-1H-pyrazol-3-yl)pyridine (L5), and 2,6-bis(1-m-methylphenyl-5-phenyl-1H-pyrazol-3-yl)pyridine (L6) were synthesized and characterized. Their palladium complexes catalyzed Suzuki–Miyaura cross-coupling revealed that the catalytic activities of these complexes were in the order of PdCl2-L5>PdCl2-L1>PdCl2-L6>PdCl2-L2>PdCl2-L3>PdCl2-L4. With a low Pd loading of 10−5 mol%, PdCl2-L1 showed a high activity. The turnover numbers (TONs) were up to 58,000,000 for 4-bromobenzotrifluoride. [Copyright &y& Elsevier]

Abstract: Three new Fe-containing MOFs, H3O[Fe5(BTC)3(OAc)2(DMF)2]·H2O 1, [FeNa(m-BDC)2]·NH2(CH3)2 2 and [N(CH3)4]2[Fe3(HBTC)(BTC)2(H2O)]·5.5H2O 3 (BTC=1,3,5-benzenetricarboxylate, m-BDC=1,3-benzene-dicarboxylate), have been synthesized from the solvothermal reactions of iron salts and carboxylate ligands. The framework of 1 is constructed from two kinds of secondary building units (SBUs): the sinusoidal chain of iron octahedra SBU [Fe2(COO)6] n 2 n − and paddle-wheel SBU [Fe2(COO)4(DMF)]. Compound 1 represents the first example of Fe-containing MOFs constructed from two kinds of SBUs. The framework of 2 is built from zigzag-chain SBUs [FeNa(COO)6] n 3 n − and m-BDC linkers. The framework of 3 is formed by linear tri-nuclear iron SBUs [Fe3(COO)8(H2O)]2− and triangular BTC linkers. To our knowledge, the Fe-containing sinusoidal chain SBU in 1, zigzag-chain SBU in 2 and linear tri-nuclear iron SBU in 3 are found in Fe-containing MOFs for the first time. Magnetic investigation indicates the present of antiferromagnetic exchange interaction within the iron units of compounds. [Copyright &y& Elsevier]