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New heteronuclear Zn2Ln2 clusters [Zn2L2Ln2(hfac)6] (Ln = Eu (1), Tb (2) and Dy (3)) have been synthesized based on a flexible Schiff base (H2L = N,N′-bis(salicylidene)-3,6-dioxa-1,8-diaminooctane) and β-diketonate ligand (hfac = hexafluoroacetylacetonate). The structures of the isomorphous complexes 1–3 were determined by single-crystal X-ray crystallography. Photophysical studies indicate that the short intramolecular distance of Zn…Ln allows energy transfer from the Zn2L2-based sensitizers to the Eu(iii) and Tb(iii) centres; the lanthanide luminescence is indeed “lighted up” by the excitation of the zinc complex. More interestingly, white light emission was realized by codoping Eu(iii) ion into the Dy(iii) complex for the first time. [ABSTRACT FROM AUTHOR]

Two type lanthanide complexes obtained by salen-type ligand N,N'-ethylenebis(salicylideneimine) (HL) and N,N'-ethylene-bis(3-methoxysalicylideneimine) (HL) have been isolated. They are 2D coordination polymer [Yb(HL)(NO)] ( 1), mononuclear Ln(HL)(NO) [Ln = Sm ( 2), Ho ( 3)]. The structures of 1- 3 were determined by single crystal X-ray crystallographic studies and their photophysical properties were investigated. [ABSTRACT FROM AUTHOR]

Abstract: A biphenyl-linked bis-β-diketone ligand, 3,3′-bis(3-phenyl-3-oxopropanol)biphenyl (BPB) has been prepared for the syntheses of a series of dinuclear lanthanide complexes. The ligand bears two benzoyl β-diketonate sites linked by a 3,3’-biphenyl spacer. Reaction of the doubly negatively charged bis-bidenate ligand with lanthanide ions forms triple-stranded dinuclear complexes Ln2(BPB)3 (Ln=Nd (1), Sm (2), Eu (3), Yb (4) and Gd (5)). Electrospray mass spectrometry is used to identify the formation of the triple-stranded dinuclear complexes 1–5, which have been further characterized by various spectroscopic techniques. The complexes display strong visible and NIR luminescence upon excitation at ligands bands around 360nm, depending on the choice of the lanthanides, and the emission quantum yields and luminescence lifetimes of 2–3 have been determined. It shows that the biphenyl-linked ligand BPB is a more efficient sensitizer than the monodiketone ligand DBM (dibenzoylmethane), through the comparisons of Ln2(BPB)3 and Ln(DBM)3 on their photoluminescent properties. [Copyright &y& Elsevier]

Abstract: Three novel N,N′-bis(2-hydroxy-3-methoxybenzylidene)-1,3-diaminopropane dimeric lanthanide complexes, namely, [{H2L}Sm(NO3)3]2·H2O (1), [{H2L}Gd(NO3)3]4·CH3OH (2), [{H2L}Lu(NO3)3]4·H2O (3) (H2L= N,N′-bis(2-hydroxy-3-methoxybenzylidene)-1,3-diaminopropane) and three new N,N′-bis(2-hydroxy-3-methoxybenzylidene)-1,3-diaminopropane 3d-Gd heterodinuclear complexes, namely, [{LCo}(CH3COO)(CH3COOH)Gd(NO3)2] (4), [{LNi(MeOH)2}Gd(NO3)3]·2MeOH (5) and [{(L)Zn(HNO3)}Gd(NO3)3]·NO3·H3O·MeOH (6) have been synthesized and isolated. X-ray crystallographical analysis reveals that complexes 1–3 are isomorphic with unique dimeric topology. Complexes 4–6 are of discrete 3d–4f dinuclear cores. Magnetic properties of complexes 2 and 4–6 are systematically investigated. Complexes 4 and 5 are ferromagnetic, while 2 and 6 are antiferromagnetic. [ABSTRACT FROM AUTHOR]

Abstract: Three Salen-like gadolinium complexes, namely, mononuclear (4f) complex [{H2L}Gd(NO3)3] (1), heterodinuclear (3d–4f) complex [{LCu}Gd(NO3)3]·0.25H2O (2) and dimeric heterotrinuclear (3d–4f–3d′) complex [{LCu}Gd(H2O)3{Fe(CN)6}]2·6H2O (3) [H2L = N,N′-ethylene-bis(3-methoxysalicylideneimine)] have been synthesized by stepwise reactions. X-ray diffraction analysis reveals that 1 is of a discrete structure in which H2L coordinates to gadolinium ion through O2O2 moiety. Then, addition of Cu(Ac)2·H2O to the mononuclear lanthanide complex yields expected heterodinuclear (3d–4f) complexes [{LCu}Gd(NO3)3]. 3 features a unique 1D ladder-like topology structure through the intermolecular double links of Cu–N bonds. The measurement of variable-temperature magnetic susceptibility reveals that complex 1 exhibits antiferromagnetic interaction while 2 and 3 exhibit ferromagnetic interaction between spin carriers. The correlations between the structure and magnetism are described and discussed. [Copyright &y& Elsevier]

Abstract: Three one-dimensional (1D) heterospin trimetallic chain-like polymers [{LCu(H2O)}Ln(MeOH)(H2O)2{(μ-CN)2Fe(CN)4}]·2H2O (1, Ln=La; 2, Ln=Nd; 3, Ln=Gd) were prepared by substitution of the nitrato ligands in [LCuLn] complexes with [Fe(CN)6]3− ions (H2L= N,N′-bis(3-methoxysalicylidene)propane-1,2-diamine). Single-crystal X-ray diffraction analysis revealed that the methyl on the salen-type ligand impeded the connection between cyanide groups and Cu(II) ions efficiently. Consequently, three novel one-dimensional (1D) trimetallic chain-like polymers were obtained with the linker [Fe(CN)6]3− ions interacting only with the lanthanide ions. The magnetic investigation for 3 indicated a ferrimagnetic chain may form. [Copyright &y& Elsevier]

Abstract: Reactions of H2L [H2L= N,N′-bis(3-methoxysalicylidene)propane-1,2-diamine] and Ln(NO3)3 ·6H2O give rise to two different mononuclear 4f complexes, namely, {[(H2L)La(NO3)3(MeOH)]·H2O} n (1) and [(H2L)Nd(NO3)3] (2). Further additions of Cu(Ac)2 ·H2O to the mononuclear 4f complexes yield expected heterodinuclear Cu-4f complexes [LCu(Me2CO)Ln(NO3)3] (3, Ln=Nd; 4, Ln=Eu; 5, Ln=Dy). Complex 1 is a unique 1D polymeric chain structure, and 2 is one of the few structurally characterized discrete hexadentate salen-type mononuclear 4f complexes. Complexes 3–5 are similar to their analogues. However, they are prepared by a reversed synthetic route in contrast to their isomorphic complexes. Electrochemical behavior of heterodinuclear Cu-4f complexes 3–5 has been examined by cyclic voltammetry in acetonitrile. The redox potential of heterodinuclear Cu-4f complexes 3–5 shows significant anodic shift comparing to that of mononuclear copper complex (LCu). A tendency of anodic shift was observed in a sequence of 3 < 4 < 5. This results from the modulating effect of coordination geometry around Cu(II) ion on redox potential. [Copyright &y& Elsevier]

Two new hetero-metallic complexes [LnNa 2 (L) 2 (bta)(CH 3 OH)]∙nH 2 O∙mCH 3 OH (Ln = Dy ( 1 ), n = 1, m = 0; Er ( 2 ), n = 0, m = 1) supported by rigid hexadentate salen-type (H 2 L = N , N ′-bis(2-oxy-3-methoxybenzylidene)-1,2-phenylenediamine) and β-diketonate (bta = benzoyltrifluoroacetone) ligands have been designed and synthesized. Structural analysis reveals that the Ln 3+ ion has a typical double-decker sandwich structure with a distorted bicapped triangular prism. The magnetic analysis unveils that both complexes 1 and 2 are of single molecule magnet behavior, and both of them can be regarded as rare SMMs based on the salen-type ligand with a double-decker structure. [ABSTRACT FROM AUTHOR]

Two new complexes [{CuL}Sm(H 2 O) 3 {Fe(CN) 6 }] 2 ·6H 2 O ( 1 ) [{CuL} 2 Pr(H 2 O){Fe(CN) 6 }] 2 ·4H 2 O ( 2 ) (H 2 L = N , N′ -ethylenebis(3-methoxysalicylideneimine)) have been prepared by reactions of acyclic compartmental Schiff-base heterodinuclear 3d–4f compound [{CuL}Ln(NO 3 ) 3 ] (Ln = Sm & Pr) with K 3 [Fe(CN) 6 ]. Crystal structures of both 1 and 2 reveal unique topology structures. 1 shows a dimeric heterotrinuclear [{CuL}Sm(H 2 O) 3 {Fe(CN) 6 }] 2 while 2 displays a dimeric heterotetranuclear [{CuL} 2 Pr(H 2 O){Fe(CN) 6 }] with distorted sandwich moieties [{CuL} 2 Pr]. Both 1 and 2 form similar 1D ladder-like structure through the intermolecular double bridges of Cu–N bonds. The measurement of variable-temperature magnetic susceptibility reveals that both complexes 1 and 2 exhibit antiferromagnetic interaction between spin carriers. [ABSTRACT FROM AUTHOR]

Abstract: A series of four m-ferrocenylbenzoate [m-ferrocenylbenzoate = Na(m-OOCH4C6Fc), Fc = (η 5-C5H5)Fe(η 5-C5H4)] copper(II) complexes Cu2(μ 2-OOCH4C6Fc)4(CH3OH)2 (1), Cu(η 2-OOCH4C6Fc)2(2,2′-bpy) (2), Cu(η 2-OOCH4C6Fc)2(1,10-phen) (3) and [Cu(η 2-OOCH4C6Fc)2(4,4′-bpy)] n (4) (bpy = bipyridine, 1,10-phen = 1,10-phenanthroline) have been synthesized by reactions of Cu(CH3COO)2·H2O with Na(m-OOCH4C6Fc) and three types of N-donor ligands, respectively. X-ray diffraction analysis reveals that 1 shows a dimeric structure with a Cu⋯Cu distance of 2.5872(16) Å. 2 and 3 exhibit a mononuclear structure. The adjacent mononuclear molecules are packed into a one-dimensional (1D) chain through the π–π interactions between the bpy rings in 2 or phen rings in 3. 4 displays a 1D zigzag chain structure. In 1, the m-OOCH4C6Fc anion adopts the bidentate-bridging coordination mode, whereas it adopts the bidentate-chelating coordination mode in 2–4. Magnetic study indicates that an antiferromagnetic interaction between the CuII ions exists in 1. [Copyright &y& Elsevier]

Abstract: By introducing different quinolone antibacterial drugs into the octamolybdates POMs, four new compounds, [CuII(L1)2(H2O)2]H2[β-Mo8O26]·4H2O (1), [CuII 2(L2)4][δ-Mo8O26]·4H2O (2), [CuII 2(L3)2(H2O)2][β-Mo8O26] (3), [CuII 2(L4)2(H2O)4][β-Mo8O26]·2H2O (4) (where L1 =Enrofloxacin; L2 =Pipemidic Acid; L3 =Norfloxacin; L4 =Enoxacin), have been synthesized and characterized by routine physical methods and single crystal X-ray diffraction. In compound 1, isolated Cu–Enrofloxacin coordination subunits array the both sides of β-Mo8O26, forming 3D supramolecular structure via noncovalent interactions. And the Cu–Pipemidic Acid subunits covalently link δ-Mo8O26 to form 3D supramolecular structures via short interactions in 2. In 3, the Cu–Norfloxacin motif exhibits 1D chain structure, and the tetra-dentate β-[Mo8O26]4− clusters interact with neighboring chains to construct a 2D sheet. Similar to that of 3, the Cu–Enoxacin subunit in 4 exhibits 1D chain structure, and the bi-dentate β-[Mo8O26]4− clusters interact with neighboring chains to construct a 2D sheet. Due to the introduction of different drug molecules, the octamolybdates POMs exhibit different isomers and structures, which bring different properties. The antitumor activities of compounds 1–4 in vitro were studied by MTT experiments, and the results show that introduction of different drug molecules onto the polyoxoanion surface can affect their antitumor activities. [Copyright &y& Elsevier]