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Two new salts, [NO2BrBzPy]2[M(mnt)2] ([NO2BrBzPy]+= 1-(2′-bromo-4′-nitrobenzyl)pyridinium; mnt2−= maleonitriledithiolate; M = Ni(1), Pd(2)) have been prepared and characterized by elemental analyses, IR, UV, ESI-MS spectra, TG, and single-crystal X-ray diffraction. The results reveal that when the metal ion is changed from Ni(II) to Pd(II), the crystal system, and the dihedral angles between the phenyl and pyridine rings and the C-C-N reference plane of the cation, and the stacking modes of the anions and the cations are evidently different. Some weak interactions such as C–H···Br, C−H···O, C−H···N and C−H···S hydrogen bonds, p or stacking interactions in 1 and 2 play important roles in the molecular stacking and generate a 2D structure.

The self-assembly of [Co(NCS)4]2− anion and substituted benzyltriphenylphosphonium cations [4RBzTPP]+ (R = H(1), NO2(2)) results in the forming of two new hybrid materials, [BzTPP]2[Co(NCS)4](1) and [4NO2BzTPP]2[Co(NCS)4](2). The Co(II) ions of the [Co(NCS)4]2− anions in 1 form a 1D chain through S⋯S interactions with the S⋯S distance of 3.458 A, while the C–H⋯S, C–H⋯O hydrogen bond and p⋯π interaction were found in 2. Magnetic susceptibility measurement in the temperature range 2–300 K shows that 1 exhibits a magnetic coupling interaction from ferromagnetic to antiferromagnetic around 30 K as the temperature is lowered, while 2 shows weak antiferromagnetic coupling behavior.

Two tetrabromocuprate (II) salts with substituted benzyl pyridinium, [BzPy]2[CuBr4](1) and [4NO2BzPy]2[CuBr4](2) ([BzPy]+ = 1-benzylpyridinium; [4NO2BzPy]+ = 1-(4′-nitrobenzy- lpyridinium), were synthesized and characterized by elemental analysis, IR, MS, and single-crystal X-ray diffraction. The two salts comprise a [CuBr4]2−anion and two cations, and the [CuBr4]2−anion exhibits a distorted tetrahedral coordination geometry. The weak interactions such as p…π, π…π, C-H…π, C−H…Br or C−H…O hydrogen bonds play important roles in the stacking and stabilization of the two salts, and give rise to a 3D network structure. In addition, the two salts show good antibacterial activities for colibacillus, aurococcus, bacillus subtilus and bacillus thuringiensis.

Two new tetranuclear copper (II) macrocyclic complexes, [Cu4L(OAc)2(OH)2](ClO4)2·2MeCN 1 and [Cu4L (OAc)2(OH)2](PF6)2(H2O)2 2, have been obtained via condensation of 2,6-diformyl-4-methylphenolate with N,N′-bis(3-aminopropyl)-2-thiophenoethylamine in the presence of copper (II) ions. The complexes were characterized by IR, ES-MS and X-ray diffraction techniques. It shows the similar chair-shaped Cu4O4 core structure for these two macrocyclic complexes, which is composed of two kinds of crystallographically independent Cu(II) ions. The coordination spheres of the Cu(II) ions are distorted square pyramid and approximate square-planar configuration, respectively. In addition, it was found that the crystal structures are stabilized by abundant hydrogen bonds between perchlorate anions and adjacent macrocyclic units for complex 1. The network structure of 2 was maintained by π–π stacking of thiopheno groups and C H···F hydrogen bond interactions between adjacent macrocycles. The variable temperature magnetic susceptibility of complex 1 was measured in the temperature range of 2–300 K. The best fitting with a quasi-butterfly magneto-structural model gave the magnetic exchange parameters of Jbb = −197.6 cm−1, Jwb1 = −60 cm−1 and Jwb2 = 103.5 cm−1.

A new mononuclear nickel(II) complex, [NiL2] (HL = ((2-(5-fluoro-2-hydroxybenzyl)(2-(imidazole-2-yl)ethyl))imine), has been synthesized and characterized by IR, UV–vis and X-ray diffraction technique. The X-ray crystal structure of the complex shows that the coordination environment around Ni(II) ion is an approximate octahedron. Each molecule connects with four adjacent neighbors through strong hydrogen bonding interactions (N–H···O, d(N–O) = 2.687 A and ∠N–H···O = 158.3(1)°), forming a supramolecular network. The interaction of the complex with DNA was monitored using agarose gel electrophoresis. The results show that the complex has DNA cleavage activity. The cyclic voltammogram shows one pair of anodic and cathodic peaks with E1/2 = −1.06 V, assigned to the Ni(II)/Ni(I) couple.

Two molecular materials, [3RBzTPP][Ni(mnt)2] (mnt2− = maleonitriledithiolate, [3RBzTPP]+ = 3-R-benzyltriphenylphosphinium, R = CN(1), F(2)), have been investigated and characterized by elemental analyses, IR, UV spectroscopy, X-ray diffraction and magnetic susceptibility measurements. The [Ni(mnt)2]− anions of 1 and 2 stack into a column through the Ni⋯S or/and S⋯S interactions with a Ni⋯S distance of 3.765 A for 1 and with the Ni⋯S and S⋯S distances of 3.654 A and 3.681 A for 2. The weak C H⋯N, C H⋯F hydrogen bonds and π⋯π stacking interactions result in the forming of a 3D network structure. Magnetic susceptibility measurements in the temperature range 2–300 K show that 1 shows an antiferromagnetic coupling behavior with θ = −9.3 K, and 2 exhibits a spin-gap transition with Δ/kb = 945.0 K around 217 K.

Two new coordination polymers of Robson-type macrocycles, [Cu2L1(μ-ClO4)2]∞ (1) and [Cu2L2(μ-ClO4)2]∞ (2) (where H2L1and H2L2 are the [2+2] condensation products of 2,6-diformyl-4-flurophenol with 1,3-diaminopropane and 2-hydroxy-1,3-diaminopropane, respectively), have been synthesized and characterized. The intriguing feature is that intermolecular perchlorato bridges occur between adjacent copper(II) centers. The cyclic voltammograms of the complexes show that each complex undergoes two pseudo-reversible processes with the half wave potentials, −0.361 V and −0.729 V for 1, and −0.372 V and −0.744 V for 2, respectively. Magnetic susceptibility was measured for 1 and 2 over a temperature range of 2–300 K. The optimized magnetic data were J = −359.6 cm−1, j′ = −30 cm−1 and R = 6.8 × 10−8 for 1 and J = −411 cm−1, j′ = −26 cm−1 and R = 2.4 × 10−7 for 2, respectively. The data reveal antiferromagnetic couplings between the copper(II) ions of intra- and intermolecular units.

The self-assembly of [BzEtPy]+([BzEtPy]+ = benzyl-4-ethylpyridinium) cation and the [Ni(mnt)2]− (mnt2− = maleonitriledithiolate) anion results in the forming of a new molecular solid [BzEtPy][Ni(mnt)2](1), in which the anions and cations stack into columns and the Ni(III) ions form a 1D zigzag alternating chain through Ni···S and π···π interactions between [Ni(mnt)2]− anions with the Ni···Ni distances of 3.886 A and 4.781 A, and the four columns of cations create cubic-like large channel in which the [Ni(mnt)2]− columns are located. Magnetic susceptibility measurements show that 1 exhibits a spin gap transition around 90 K.

Two new molecular solids, [BzPyNH2][Ni(mnt)2](1) and [2-NpCH2PyNH2][Ni(mnt)2](2) (mnt2− = maleonitriledithiolate, [BzPyNH2]+ = 1-benzyl-2-aminopyridinium and [2-NpCH2PyNH2]+ = 1-(2′-naphthylmethylene)-2-aminopyridinium) have been characterized structurally and magnetically. The Ni(Ш) ions of 1 and 2 form a 1D magnetic chain within a [Ni(mnt)2]− column through Ni⋯N or π⋯π interactions. Some weak interactions observed in 1 and 2 give further rise to a 2D structure. The overlapping fashions of the [Ni(mnt)2]− anions are different when the 2-aminopyridine ring was fixed and the phenyl ring changed into the naphthyl ring of the cation. Magnetic susceptibility measurements in the temperature range 2–300 K show that 1 is weak antiferromagnetic coupling, while 2 exhibits a novel and interesting spin-gap transition around 140 K with Δ/kb = 381.4 K.

A new dumbbell-type 4,4′-bipy-bridged dinuclear copper(II) complex, [Cu2(4,4′-bipy)L2(H2O)2](ClO4)4·8CH3OH·10H2O, where L = 1-[bis(3-aminopropyl)amino]-2- propanol and bipy = bipyridine, has been synthesized and characterized, X-ray crystallographic analysis shows that the [Cu2(4,4′-bipy)L2(H2O)2]4+ cations and water molecules generate layer structures extending parallel to bc planes through hydrogen bonding interactions of O–H···O and C–H···O. The layers are also connected by hydrogen bonding interactions involving methanol, water, and perchlorate anions. These interactions lead to the formation of rectangular channels of 12.3 A × 6.0 A along the crystallographic c axis. Perchlorate anions fill in each channel in a sandwich-like packing mode, they are joined with the adjacent layers by water heptamers. Magnetic susceptibility measurements show that the magnetic exchange interaction is weak although it has a regular π-type electron transfer pathway. Furthermore, the electrochemical and thermogravimetric properties of the complex were also investigated.

Two new salts, [BzTPP]2[Cu(mnt)2] (1) and [4NO2BzTPP]2[Cu(mnt)2] (2) (BzTPP+ = benzyltriphenylphosphonium and mnt2− = maleonitriledithiolate) have been prepared and characterized by elemental analyses, UV, IR, molar conductivity and single-crystal X-ray diffraction. The single-crystal structure analysis shows that 1 crystallizes in the monoclinic space group P21/n, while 2 crystallizes in the triclinic space group P−1. The effects of weak intramolecular interactions such as C–H···O, C–H···S, C–H···N, C–H···Cu hydrogen bonds and p···π, π···π stacking interactions in the solids generate a 3D network structure. It is noted that the change in the molecular topology of the counteraction when the 4-substituted group in the benzyl ring is changed from H to NO2 results in differences in the crystal system, space group, weak interactions and the stacking mode of the cations and anions of 1 and 2. The magnetic susceptibilities of these salts measured in the temperature range 2.0 to 300 K show weak ferromagnetic coupling features with θ = 2.05 × 10−2 K for 1 and 5.13 × 10−3 K for 2.

An ionic pair complex, [FClBzDMAP]2[Pd(mnt)2] (1) , ([FClBzDMAP]+ = [1-(4′-fluoro-2′-chlorobenzyl)-4-dimetylamino pyridinium, mnt2− = maleonitriledithiolate), was synthesized and characterized by elemental analyses, IR, UV-vis spectra, molar conductivities and single crystal diffraction. The crystal belongs to the triclinic system, space group P-1 with cell constants a = 8.3472(8) A, b = 9.3988(9) A, c = 13.5875(14) A, α = 76.676(1)°, β = 86.036(1)°, γ = 71.182(1)°, Z = 1. It is interesting that the [FClBzDMAP]+ cations (C) and the [Pd(mnt)2]2− anions (A) in 1 stack into a 1D alternating CC-A-CC-A-CC column along ab direction, while the cations form a 1D column along bc direction. Some weak interactions such as p … π, π … π, Cl … S, and C─ H … N interactions in the crystal play important roles in the self-assembly process and give rise to a 3D network structure.

Syntheses, structural characterizations, magnetic behaviors and theoretical analyses of two new ion-pair complexes, [IFBzIQl][Ni(mnt)2](1) and [IClBzIQl]2[Ni(mnt)2]2 · MeCN(2) [IFBzIQl][Ni(mnt)2] ([IFBzIQl]+ = 1-(2′-fluoro-4′-iodobenzyl)isoquinolinium, [IClBzIQl]+ = 1-(2′-chloro-4′-iodobenzyl)isoquinolinium, mnt2− = maleonitriledithiolate), have been investigated. In crystal of 1, the [Ni(mnt)2]− anions and the [IFBzIQl]+ cations stack into an alternating column through π⋯π stacking interactions. The anions of both 1 and 2 form a dimer via π⋯π stacking and S⋯S short interactions between the [Ni(mnt)2]− anions. The overlapping mode of two neighboring [Ni(mnt)2]− anions in the dimer is the Ni-ring fashion with a Ni⋯Ni distance of 4.076 A for 1, and ring–ring fashion with the Ni⋯Ni and S⋯S distances being 4.395 and 3.593 A for 2. Some weak interactions such as π⋯π, C⋯N, C–H⋯F or C–H⋯N in 1 and 2 play a crucial role in stacking and stabilizing the crystal lattice, and give a 3D network structure and exchange pathways of the magnetic interaction for 1 and 2. Magnetic susceptibility measurements for 1 and 2 in the temperature range 1.8–300 K show that the overall magnetic behavior indicates the presence of antiferromagnetic interaction, while 2 exhibits an activated magnetic behavior in the high-temperature region (HT) together with a Curie tail in the low-temperature region (LT).

Two new ion-pair complexes, [FBrBzPyN(CH 3 ) 2 ] 2 [Ni(mnt) 2 ] (1) and [FBrBzPyN(CH 3 ) 2 ][Ni(mnt) 2 ] (2) (mnt 2- = maleonitriledithiolate, [FBrBzPyN(CH 3 ) 2 ] + =[1-(4'-fluoro-2'-bromobenzyl)-4-dimethylamino-pyridinium]) have been prepared and characterized by elemental analyses, UV, IR, single crystal X-ray diffraction and magnetic susceptibility. The cations (D) and the anions (A) in 1 stack into a 1 D alternating column (i.e., of type ··· DDADDADD ···) via short S···Br. N···F, C···N interactions, and C-H···Br hydrogen bonds. The cation-cation π···π stacking interactions within the columns give further rise to a 2D network structure. Compound 2 forms a 3D structure in which the Ni(III) ions stack into a uniform 1 D zigzag magnetic chain through Ni···S, Ni···Ni, or π···π interactions with a Ni···Ni distance of 4.024 A. Magnetic susceptibility measurements in the temperature range 2-300 K show that 1 is expected to be diamagnetic, and 2 exhibits an interesting spin-gap transition (Δ/k b = 460.6 K) around 155 K.

Two new salts, [2-NaMePy]2[Ni(i-mnt)2] (1) and [2-NaMe-4-MePy]2[Ni(i-mnt)2] (2) ([2-NaMePy]+ = 1-(2′-naphthylmethyl)pyridinium, [2-NaMe-4-MePy]+ = 1-(2′-naphthylmethyl)-4-methylpyridinium and i-mnt2− = iso-maleonitriledithiolate), have been prepared and characterized by elemental analyses, UV, IR, molar conductivity, and single crystal X-ray diffraction. The anions in 1 form a 1-D chain through short C ··· N interactions between the anions, while the cations in 2 stack a 1-D column via C–H ··· π and π ··· π stacking interactions between the cations. The effect of weak intramolecular interactions such as C–H ··· N, C–H ··· S, C–H ··· Ni hydrogen bonds, and π ··· π stacking interactions between the cations and the anions further generate a 3-D network structure. The change of the molecular topology of the countercation when the 4-substituted group in the pyridine ring is changed from H atom to CH3 group results in different crystal system, space group, and the stacking mode of the cations and anions of 1 and 2.

A new ion-pair complex, bis[1-(4 ′ -nitrobenzyl)-3-cyanopyridinium]-bis(maleonitrile-dithiolate)nickelate(II)(1) ([NO 2 BzCNPy] 2 [Ni(mnt) 2 ]), was synthesized and characterized by elemental analyses, IR, MS spectra and single crystal diffraction. The crystal belongs to the triclinic system, space group P-1 with cell constants a = 9.452(1) A, b = 10.395(2) A, c = 11.117(2) A, α = 96.56(1)°, β = 113.94(1)°, γ = 112.68(1)°, Z = 1. The structure was solved by direct methods and refined to R1 = 0.0415 (wR 2 = 0.0771). The structure analysis reveals that the weak C… N, C-H… π, C-H… O, C-H… N interactions and π… π stacking interactios in the crystal play important roles in the self-assembly process and give rise to a 3D network structure.

A new ion-pair complex, bis(1-benzyltriphenylphosphinium) bis(1,2,5-thiadiazole-3,4-dithiolato)nickelate(II), [BzTPP]2[Ni(tdas)2](1), has been prepared and characterized by elemental analyses, UV, IR, MS spectrum, molar conductivity and single crystal X-ray diffraction. The title complex crystallizes in the triclinic space group P-1, a = 9.098(1) A, b = 9.666(1) A, c = 29.573(3) A, α = 83.81(1)°, β = 81.97(1)°, γ = 78.83(1)°, V = 2,517.5(4) A3, Z = 2. The unit cell contains two [BzTPP]+ and two halves of [Ni(tdas)2]2− anions in which the anion exhibits a quasi-planar structure. The [BzTPP]+ cation adopts a conformation where four phenyl rings are twisted to the C–C–P reference plane. The weak cation–cation C–H···π, π···π interactions and anion–cation C–H···N hydrogen bonds between the anion and cation play an important role in the stacking and stabilizing of the title complex. The title new ion-pair complex, bis(1-benzyltriphenylphosphinium) bis(1,2,5-thiadiazole-3,4-dithiolato)nickelate(II), [BzTPP]2[Ni(tdas)2](1), contains two [BzTPP]+ and two halves of [Ni(tdas)2]2− anions in which the weak cation–cation C–H···π, π···π interactions and anion−cation C–H···N hydrogen bonds between the anion and cation play an important role in the stacking and stabilizing of the title complex.

A novel binuclear manganese Mn(II) macrocyclic complex with two pyridylmethyl pendant arms, [Mn2II(H2L)(μ-OAc)2](ClO4)2 · H2O, has been synthesized and characterized crystallographically and magnetically. The crystal structure of the complex shows that two manganese ions locate in the same head of the macrocycle, leaving an uncoordinating cavity to catch protons through oxide of phenolate and the nearby imine groups in another head. The electrochemical study demonstrates that the complex gives two couples of redox peaks with E1/2 of 0.3775 V and 0.8409 V, respectively. The variable temperature magnetic susceptibility measurement on the sample displays weak antiferromagnetic interaction between two manganese (II) with the J = −3.733(7) cm−1. This complex exhibits a moderate activity for catalyzing disproportionation of H2O2 to O2.

A new molecular magnet, [NO2BrBzPyCH3][Ni(mnt)2] (1) ([NO2BrBzPyCH3]+ = 1-(2′-bromo-4′-nitrobenzyl)-2-methylpyridinium, and mnt2– = maleonitriledithiolate), has been prepared and characterized by single crystal X-ray diffraction and magnetic measurements. The Ni(III) ions of 1 form a quasi-one-dimensional alternating zig-zag magnetic chain within a Ni(mnt)2– column by intermolecular Ni···S, Ni···Ni or π···π interactions, and the [NO2BrBzPyCH3]+ cations stack into a column via weak Br···O interaction, p···π stacking interactions and C-H···O hydrogen bonds between the cations. Magnetic susceptibility measurements in the temperature range 1.8-300 K show that 1 exhibits a spin-gap transition around 180 K, and an antiferromagnetic interaction in the high-temperature phase (HT) and spin gap behavior in the low-temperature phase (LT). The transition for 1 is a second-order phase transition as determined by DSC analyses.

New alkaline-earth metal cryptates [ML](ClO4)2 · solvent (M = Ca2+, Sr2+, Ba2+; L = 1,4, 12,15,18,26,31,39,42,43,44-undecaazapentacyclo-[13.13.13.16,10.120,24.133,37]-tetratetraconta-4, 6, 8, 10(44), 11,18,20,22,24(43),25,31,33,35,37(42),38-pentadecaene) were synthesized by [2 + 3] template condensation of tris(2-aminoethyl)amine with 2,6-diformylpyridine and characterized by physical methods. The crystal structure of the calcium cryptate was determined. The central atom is nine coordinate with three pyridyl and six imino nitrogen atoms. The coordination polyhedron can be described as slightly distorted tricapped trigonal prism.

A meso cobalt(II) complex, [Co(II) L2L2′] · 4.25H2O, has been synthesized from heterocyclic Schiff‐base ligand N‐ (2‐pyridyliene)‐2‐pyrimidylamine (L1) with inorganic cobalt(II) Salt, and its coordination of chemistry has also been investigated. Carmine block crystals of [Co(II) L2 L2′] · 4.25H2O were obtained from the filtrate which was resulted from the addition of a hot alcohol solution of N‐ (2‐pyridyliene)‐2‐pyrimidylamine (L1) into the alcohol solution of the CoCl2 · 6H2O. Single‐crystal X‐ray diffraction analysis indicates that it crystallizes in a trigonal system with space group R‐3c, with a=24.820(4), b=24.820(4), c=21.010(4) A, α=90°, β=90°, γ=120°, V=11209(3) A3, Z=36, Mr=533.413, F(000)=5060, Dc=1.439 g/cm3, μ(MoKα)=0.742 mm−1, R=0.0666, and wR2=0.2734 for 2229 reflections with I>2σ (I). The Co atom is coordinated in a elongated octahedral geometry by two O atoms, which produced by partial hydrolysis of N‐ (2‐pyridyliene)‐2‐pyrimidylamine (L1), and four N atoms, among which two N atoms were f...

Three dimetallic complexes of the unsymmetrical macrocycle (L)2−, [M1M2L]2+ (M1M2 = NiNi, CuZn, CuCd), have been synthesized by cyclocondensation between N,N′-bis(3-formyl-4-n-butylsalicylidene)ethylenediimine and 1,3-diaminopropane in the presence of M 1 2 + and M 2 2 + .The crystal structure of the complex [Ni2L4(H2O)2](ClO4)2 · 0.5CH3OH was determined by X-ray diffraction techniques.The asymmetric unit contains two complete macrocyclic complexes which are nevertheless quite similar to one another.The nickel–nickel separations, bridged by the two phenoxides, are 2.977 A and 2.982 A.In each molecule, the Ni(II) located in the ethylene chain linked site has a square planar geometry whereas the Ni(II) located in the propylene chain linked site has an octahedral environment.The results of ES-MS and cycle voltammograms confirm that Cu–Zn, Ni–Ni form stable complexes with the macrocyclic ligand L, however the complex composed of Cu–Cd was unstable, and easily lost Cd2+ from the complex in methanol solution.The cyclic voltammograms of the complexes show that each complex undergoes a stepwise reduction process, e.g.[Ni2L]2+ with E 1 / 2 1 = - 0.862 V and E 1 / 2 2 = - 1.20 V .Magnetic measurements in the 2–300 K range indicate weak antiferromagnetism for the dinuclear nickel(II) complex with the exchange constantJ = −0.90 cm−1.

Seven lathanide cryptates [LnL](NO)3 · nH2O (n=1–3; Ln=La, Ce, Pr, Sm, Eu, Gd, Tb) were synthesized by the reactions of lanthanide nitrates with free ligand L (L was derived from the (2 + 3) condensation of 2,6-diformyl-pyridine (dfp) with tris-(2-aminoethyl) amine (tren)) and characterized by physical methods. ES-MS spectra show that except for La(III) cryptate, the other six are all stable in solution. The crystal structure of the Eu(III) cryptate showed a tricapped prismatic coordination geometry.

A new neodymium cryptate [NdL](NO)3·H2O (L = 1,4,12,15,18,26,31,39,42,43,44-undecaazapentacyclo-[13.13.13.16,10.120,24.133,37]-tetratetraconta-4,6,8,10(44)11,18,20,22,24(43),25,31,33,35,37(42),38-pentadecaene) was synthesized by the reaction of free ligand L with neodymium nitrate and characterized by physical methods and X-ray crystallography. It crystallizes in space group with a = 14.623(2), c = 32.682(3) A, Z = 6. Final refinement of the structure gave R = 0.042 and Rw = 0.132 . The crystal structure of Nd(III) cryptate shows a tricapped prismatic structure with coordination number nine.

A new heterodinuclear cryptate [AgCuL](ClO4−)2 was synthesized by transmetallation via its precursor [Ag2L](ClO4−)2 (L = ligand). The electrospray mass spectrum (ES-MS) showed that the heterodinuclear entity exists in the solution. The X-Ray structure analysis shows that the AgI ion has tetrahedral geometry while CuI lies in a three-coordinate environment.

A new polyoxometalate (H2bpy)2{Eu(H2O)3(PW11O39)}·6H2O 1 constructed from lacunary Keggin frameworks, has been hydrothermally synthesized and characterized by IR and X-ray single crystal diffraction. It is interesting to find that the heteropolyanions are linked to chains, and the chains are further connected into an extensive two dimension (2D) layer structure depending on hydrogen bond.

The trinuclear copper(II) cryptate [Cu3L(im)(Br)2](ClO4)3·H2O was studied, where im denotes the imidazolate anion and L is a reduced form cryptand which was synthesized by [2 + 3] Schiff-base condensation of tris(2-aminopropyl)amine with 2,6-diformylpyridine followed by reduction with NaBH4. An ES-MS spectrum confirms the presence of a Cu3L core and its dimer in the cryptate. X-Ray analysis shows that the three copper(II) centers are arranged in an isosceles triangles. Cu(1) is located in a N4Br coordination environment with a square pyramidal configuration. Cu(2) and Cu(3) showed square planar configurations with N3Br and N4 coordination environments, respectively. Two nitrogens of an imidazole anion acting as a bridging ligand link Cu(1) and Cu(3). A weak interaction was found between Cu(2) and Br(1). Both intermolecular hydrogen bonds and the weak interaction between two molecules of cryptates via ClO4− resulted in the formation of a dimer of the cryptate. The magnetic interaction in the dimer was also studied.

A novel water-soluble octaazamacrocyclic dinuclear copper(II) complex with tetra-pendant arms, [Cu 2 L] Cl 2 ∙ 5H 2 O, was synthesized by [2+2] condensation between 2, 6-diformyl-4-chlorophenol and N, N, N', N'-tetrakis(2'-aminoethyl)-1, 2-diaminopropane in the presence of Cu(OAc) 2 ·H 2 O. Single-crystal X-ray structural analysis reveals that every copper(II) adopts a trigonal bipyramid coordination configuration. Macrocyclic units are joined together by strong π – π stacking interaction with centroid–centroid distance of 3.658 A. Water pentamers with O–O distances of 2.099–2.841 A are observed in the complex. The activity of superoxide dismutase of the complex has been investigated by the nitro blue tetrazolium method.

The copper(II) complex of a new bis-N4O-hexdentate Schiff-base, in which two N,N′-dimethyl-N-(3-(2′-aminoethylimine)-5-(chlorosalicylamine))-N′-(3-imine-5-chlorosalicylamine) units are connected by an ethylene, was synthesized and structurally characterized in the solid state as a form of pentanuclear single helicate based on the square-planar coordination geometries.

The Gd atom in the title compound, [Gd(C33H39N11)]Cl3·3H2O, lies on a position of 32 point symmetry and exhibits a tricapped trigonal prismatic coordination geometry. A twofold rotation axis passes through the coordinated N atom and the opposite C atom of the pyridyl ring of the ligand, while a threefold rotation axis passes through the aliphatic N atom. The Cl atom and O atom of the uncoordinated water mol­ecule both lie on twofold rotation axes.

Four heterodinuclear cryptates [EuML(dmf)](ClO 4 ) 2 (M=Ca, Cd, Ni, Zn) were synthesized by a two-step method (L denotes deprotonated anionic cryptand synthesized by condensation of tris(2-aminoethyl)amine with 2,6-diformyl-4-chlorophenol). The ES-MS spectra of the four cryptates and the crystal structure of [EuNiL(dmf)]-(ClO 4 ) 2 .MeCN confirm that a strict dinuclear Eu I I I -M I I entity exits in the cryptates. The cyclic voltammetry and luminescence spectral investigations indicate that the introduction of second metal ions into the mononuclear Eu I I I cryptate result in a negative shift of the redox potential of Eu I I I and a change in luminescence intensity of Eu I I I . The cryptate [EuML(dmf)](ClO 4 ) 2 was shown to quench the emission of Eu I I I when M = Ni and to enhance the emission of Eu I I I when M = Ca, Cd, and Zn in the sequence: mononuclear < Eu - Ca < Eu - Cd < Eu - Zn.

The dimeric title complex, [Ho2(CH3COO)6(C12H8N2)2], lies about a centre of symmetry. Each cation is coordinated by a chelating 1,10-phenanthroline and two chelating acetato ligands, one of which also bridges the two Ho atoms. Two other bridging acetate ligands complete the coordination of the nine-coordinate holmium(III) atoms.

A new fluorenyl-substituted dioxotetraamine salicylaldehyde Schiff-base ligand (L1) has been synthesized by the non-template 1 + 2 condensation of ligand 6-(9-fluorenyl)-1,4,8,11-tetraazaundecane-5,7-dione (L) with salicylaldehyde. From reduction of L1 with an excess of NaBH4, a ditopic dioxotetraamine ligand (L2) has been obtained. The copper(II) complex of L1 has been synthesized and its properties were examined by ES-MS and variable-temperature magnetic susceptibility as well as its crystal structure being determined. Detailed studies have been made on solution chemistry of Cu(II) complex of L2 by pH-potentiometric and fluorometric titration.

In the asymmetric unit of the title compound, [LuIII(C26H34N6O2)(NO3)2]NO3·0.5H2O·0.25C4H8O2, there are two cations and two anions of the title complex, together with a water molecule and half a molecule of ethyl acetate. The Lu atom exhibits a nine-coordinate distorted tricapped trigonal-prismatic coordination geometry. The water mol­ecule is disordered, with occupation factors of 0.4 and 0.6.