Inorganic Chemistry Communications (v.12, #4)

Contents List (iii-vii).

A novel 2D organic–inorganic hybrid solid [(Cu6I4)2(bbta)2(bta)4] n (1) (bta = benzotriazole, bbta = 1,2-bis(benzotriazole)ethane) constructed from unprecedented flower-basket-shaped [ Cu 4 I I 4 ] clusters was prepared under solvothermal condition and characterized.The solvothermal reaction of the flexible ligand 1,2-bis(benzotriazole)ethane (bbta) with CuI produced a novel two-dimensional organic-inorganic hybrid solid, namely, [(Cu6I4)2(bbta)2(bta)4] n (bta = benzotriazole) (1). Novel 1D inorganic chains [ Cu 6 I 4 ] n 2 n - constructing from unprecedented flower-basket-shaped [ Cu 4 I I 4 ] clusters are observed, which are further linked by the bbta and bta ligands using rare μ3-bidging mode to generate the 2D organic–inorganic hybrid structure of 1.
Keywords: Organic–inorganic hybrid solid; 1,2-Bis(benzotriazole)ethane; [Cu4I4] cluster; Luminescence;

A novel 3D coordination polymer {[Ag2(BPT)] · NO3} n (1) (BPT = 3,5-bis(3-pyridyl)-1,2,4-triazole) was prepared under hydrothermal condition and characterized by X-ray single-crystal diffraction, elemental analysis, X-ray powder diffraction (XRPD), FT-IR, TGA and photoluminescence measurements.The hydrothermal reaction of AgNO3 and 4-amino-3,5-bis(3-pyridyl)-1,2,4-triazole (NH2-BPT) generated an unprecedented three-dimensional coordination polymer {[Ag2(BPT)] · NO3} n (1). The crystal structure reveals that two independent Ag(I) centers are linked via cisoid μ5-BPT anions to form a unique tetranuclear cluster, which is further interconnected to four neighbors to give a 3D cationic framework with dia-topology.
Keywords: Silver; 3,5-Bis(3-pyridyl)-1,2,4-triazole; Coordination polymer; Topology; Luminescence;

Construction of a 2D luminescent network with a novel asymmetric flexible ligand involving unique octameric water clusters by Wei Wei; Feilong Jiang; Mingyan Wu; Qiang Gao; Qingfu Zhang; Chunfeng Yan; Ning Li; Maochun Hong (290-292).
A two-dimensional (2D) metal-organic network, [AgL] n  · 2nH2O (1), has been obtained by reaction of silver(I) nitrate and new flexible asymmetric ligand, 2-sulfanylmethyl-4′-phenylcarboxylate-1,3,4-thiadiazole (L). Single crystal analysis shows that there is a new octameric water cluster consisting of a cyclic water tetramer and two dangling water dimmers in 1.A two-dimensional (2D) metal-organic network, [AgL] n  · 2nH2O (1), has been obtained by reaction of silver(I) nitrate and new flexible asymmetric ligand, 2-sulfanylmethyl-4′-phenylcarboxylate-1,3,4-thiadiazole (L). Single crystal analysis shows that there is a new octameric water cluster consisting of a cyclic water tetramer and two dangling water dimmers in 1. Moreover, the emissive properties of 1 in solid state at room temperature and 10 K were investigated.
Keywords: Coordination polymer; Asymmetric flexible ligand; Water cluster; Luminescence;

A new polynuclear Fe(III) cluster based on inorganic O-donor polyoxometalate and organic N-donor ligands by Quan Shi; Zhi-Ming Zhang; Yang-Guang Li; Qiong Wu; Shuang Yao; En-Bo Wang (293-295).
A new polynuclear Fe(III) cluster based on both inorganic O-donor polyoxometalate ligand and organic N-donor ligand hexamethylenetetramine (hmta), Na9(CH3-hmta)4 (hmta)2[{Fe10− x W x H15−3 x O15(hmta)2}(P2W13O51)2] · ∼70H2O (x  = 0.18) (1), has been synthesized and structurally characterized, exhibiting good electrocatalytic properties to reduce the nitrites.A new polynuclear Fe(III) cluster based on both inorganic O-donor polyoxometalate ligand and organic N-donor ligand hexamethylenetetramine (hmta), Na9(CH3-hmta)4 (hmta)2[{Fe10− x W x H15−3 x O15(hmta)2}(P2W13O51)2] · ∼70H2O (x  = 0.18) (1), has been synthesized and structurally characterized, exhibiting good electrocatalytic properties to reduce the nitrites.
Keywords: Iron cluster; Polyoxometalate; Hmta; Electrocatalysis;

Reaction of mononuclear Ln(fod)3 chelates (where fod is the anion of 6,6,7,7,8,8,8-heptafluoro-2,2-dimethyl-3,5-octanedione and Ln = Nd, Eu, Tb and Lu) with potentially bridging ligand 2,2′-bipyrimidine (bpm) in ethanol in 2:1 molar ratio afforded new dinuclear lanthanide complexes. Neodymium complex is one of the rare bpm bridged dinuclear complexes. These complexes are thermally more stable than their mononuclear analogues with 1,10-phenanthroline and 2,2′-bipyridyl.Reaction of mononuclear Ln(fod)3 chelates (where fod is the anion of 6,6,7,7,8,8,8-heptafluoro-2,2-dimethyl-3,5-octanedione and Ln = Nd, Eu, Tb and Lu) with potentially bridging ligand 2,2′-bipyrimidine (bpm) in 2:1 mole ratio in ethanol afforded new dinuclear lanthanide complexes of the form [Ln(fod)3-(μ-bpm)-Ln(fod)3]. Neodymium complex is one of the rare bipyrimidine-bridged dinuclear complexes. The absorption spectrum of the neodymium complex displays characteristic hypersensitive as well as non-hypersensitive transitions. The excitation of Eu–Eu and Tb–Tb complexes at 355 nm produces an intense red and green luminescence, respectively.
Keywords: 2,2′-Bipyrimidine; Dinuclear complexes; Neodymium; NMR; Luminescence;

CSB, a coumarin Shiff-base derivative, could be used to detect Zn(II) by both fluorescence and the naked eye. CSB has nearly no fluorescence due to rapid isomerization in the excited state. However, this isomerization is stopped because of bonding to Zn(II) ion resulting in fluorescence “turn-on” with more than 1000-fold enhanced intensity.A coumarin Shiff-base derivative, 7-hydroxy-3-(2-hydroxybenzylideneamino)-2H-chromen-2-one (CSB), was obtained by simple two-step organic synthesis from cheap and commercially available starting materials. CSB has nearly no fluorescence in CH3CN solution. However, in the presence of Zn(II) ion, a “turn-on” fluorescence was observed. Other metal ions in CSB solution show very little emission or do not show any emission. CSB can also be used as a colorimetric chemosensor for Zn(II), which is easily observed from colorless to yellow by the naked eye. The absorption maximum of CSB shows a large red shift from 374 to 452 nm upon addition of Zn(II).
Keywords: Colorimetric chemosensor; Coumarin Shiff-base; “Turn-on” fluorescence; Zn(II) ion;

A new magnesium porphyrazine (4) containing four peripheral calix[4]arene-crown-5 moieties has been prepared by cyclotetramerization reaction of calix[4]arene-crown-5 (3).The synthesis and characterization of novel magnesium porphyrazine, peripherally symmetrically derived from 1,3-alternate 26,28-[35,36-dicyano-34,37-dithia-29,32,40,43-tetraoxa-35-en]calix[4]arene-crown-5, were carried out. This compound was prepared starting from cis-1,2-dicyano-1,2-ethylenedithiolate and 1,3-alternate 26,28-bis(5′-chloro-3′-oxapentyloxy)calix[4]arene-crown-5. The new macrocycle was characterized using the techniques of UV–vis, 1H, 13C NMR, IR, MS and elemental analysis.
Keywords: Calix[4]arene; Crown ether; Porphyrazine; Magnesium complex; Polymacrocycle;

The 1D chain coordination polymer [Co(dca)2(4-bpmp)2(H2O)2] n (1, dca = dicyanamide, 4-bpmp = bis(4-pyridylmethyl)piperazine) exhibits a relatively uncommon monodentate dca binding mode. Hydrogen-bonding interactions between aqua ligands and piperazinyl nitrogen atoms within the 4-bpmp tethers promote a novel (4,6)-connected supramolecular network.The 1D chain coordination polymer [Co(dca)2(4-bpmp)2(H2O)2] n (1, dca = dicyanamide, 4-bpmp = bis(4-pyridylmethyl)piperazine) has been prepared by a solution phase method and characterized by single-crystal X-ray diffraction, IR and elemental analysis. The dca ligand adopts a relatively uncommon monodentate binding mode. Interchain hydrogen-bonding mechanisms between the unligated nitrogen atoms of the pendant dca ligands and aqua ligands promote formation of a sawtooth (4,4) supramolecular layer. In turn, hydrogen-bonding interactions between aqua ligands and piperazinyl nitrogen atoms within the 4-bpmp tethers result in a simple yet unique (4,6)-connected supramolecular network with (425262)(42566473) topology.
Keywords: Coordination polymer; Cobalt; Dicyanamide; Crystal structure; Organodiimine; Hydrogen-bonding; Supramolecular network;

Synthesis of nanoporous iminodiacetic acid sorbents for binding transition metals by Brad Busche; Robert Wiacek; Joseph Davidson; View Koonsiripaiboon; Wassana Yantasee; R. Shane Addleman; Glen E. Fryxell (312-315).
Self-assembly of IDAA ligands inside a mesoporous silica makes an effective sorbent for transition metal separations.Iminodiacetic acid (IDAA) forms strong complexes with a wide variety of metal ions. Using self-assembled monolayers in mesoporous supports (SAMMS) to present the IDAA ligand potentially allows for multiple metal–ligand interactions to enhance the metal binding affinity relative to that of randomly oriented polymer-based supports. This manuscript describes the synthesis of a novel nanostructured sorbent material built using self-assembly of a IDAA ligand inside a nanoporous silica, and demonstrates its use for capturing transition metal cations, and anionic metal complexes, such as PdCl 4 - 2 .
Keywords: Nanoporous; Sorbent; Ion exchange; Chelation; Ion chromatography; Self-assembled monolayer;

3D pillar-layered 4d–4f heterometallic coordination polymers based on pyridine-3,5-dicaboxylate and oxalate mixed ligands by Xiao-Ming Lin; Yin Ying; Li Chen; Hua-Cai Fang; Zheng-Yuan Zhou; Qing-Guang Zhan; Yue-Peng Cai (316-320).
Three 4d–4f heterometallic polymers, Ln2Ag2(Hpydc)2(pydc)2(ox) · 4H2O (Ln = Nd (1), Eu (2) and Er (3); H2Pydc = pyridine-3,5-dicarboxylic acid, H2ox = oxalic acid), have been successfully synthesized under hydrothermal condition and structurally characterized. Single-crystal X-ray diffraction analyses reveal that three compounds are isomorphous and exhibit 3D pillar-layered coordination frameworks constructed from two-dimensional lanthanide-carboxylate layers and [Ag(pydc)] pillars. Furthermore, the luminescent property of compound 2 was studied.Three 4d–4f heterometallic polymers, Ln2Ag2(Hpydc)2(pydc)2(ox) · 4H2O (Ln = Nd (1), Eu (2) and Er (3); H2Pydc = pyridine-3,5-dicarboxylic acid, H2ox = oxalic acid), have been successfully synthesized under hydrothermal condition and structurally characterized. Single-crystal X-ray diffraction analyses reveal that three compounds are isomorphous and exhibit 3D pillar-layered coordination frameworks constructed from two-dimensional lanthanide-carboxylate layers and [Ag(pydc)] pillars. Furthermore, the luminescent property of compound 2 was studied.
Keywords: Hydrothermal synthesis; Crystal structure; 4d–4f Heterometallic polymers; Luminescent property;

A novel 1-D coordination Cu(II) polymer with alternating μ1,3-squarato and binucleating polypyridylamine bridges by Thibaut LeGuet; Franz A. Mautner; Serhiy Demeshko; Franc Meyer; Richard S. Perkins; Salah S. Massoud (321-324).
The 1-D coordination polymer {[Cu2(L)(μ1,3-C4O4)(ClO4)2]·1.33 H2O} n (L  = 1,3-bis[bis(2-pyridylmethyl)aminomethyl]benzene was synthesized and structurally characterized. The structure consists of L bound to two Cu(II) centers and a bridging squarato in a μ-O1,O3-bis(monodentate) fashion.A novel 1-D coordination polymer {[Cu2(L)(μ-1,3-C4O4)(ClO4)2]·1.33 H2O} n ( C 4 O 4 2 - = 3 , 4 -dihydroxycyclobut- 3 - en - 1 , 2 -dionate , L  = 1,3-bis[bis(2-pyridylmethyl)aminomethyl]benzene was synthesized and structurally characterized by X-ray crystallography. The spectral and structural characterization, electrochemical and magnetic properties as well as thermo gravimetric analyses are reported. The structure of the complex consists of the ligand L bound to two Cu(II) centers and a bridging squarato in the 1,3-bonding mode. The coordination geometry around the Cu(II) centers is a five-coordinate with a slightly distorted square pyramidal environment which is achieved by the three N-donor atoms of each arm of the ligand L, an oxygen atom of the bridging squarato moiety and by an oxygen atom of the ClO 4 - anion. The complex shows antiferromagnetic coupling between the squarato-bridged Cu(II) ions with J  = −6.3 cm−1.
Keywords: Copper complexes; 1D complexes; Squarato bridges; Crystal structure; Magnetic properties;

A tetranuclear ferrous cluster, [(phen)2Fe(II)(CN)2Fe(II)(bpqa)]2(PF4)4  · H2O · (CH3OH)2 (bpqa = bis(2-pyridylmethyl)(2-quinolylmethyl) amine, phen = 1,10-phenanthroline), has been synthesized via self-assembly reaction. Both the structural analysis and magnetic measurements revealed its mix-spin state for the spin alignment within the tetranuclear cluster.A tetranuclear ferrous cluster, [(phen)2Fe(II)(CN)2Fe(II)(bpqa)]2(PF4)4  · H2O · (CH3OH)2 (abbreviated as 1-(PF6)4) (bpqa = bis(2-pyridylmethyl)(2-quinolylmethyl)amine, phen = 1,10-phenanthroline), has been synthesized via self-assembly reaction. Single-crystal X-ray diffraction analysis shows that 1-(PF6)4 is a tetranuclear cyanide-bridged ferrous cluster, which is crystallized in centrosymmetric C2/c space group of monoclinic crystal system. The temperature (5–300 K) dependent magnetic susceptibility of 1-(PF6)4 corresponds to a mixed-spin state with two high spin and two low spin Fe(II) ions within the cluster.
Keywords: Cluster; Square; Mixed-spin; Cyanide; Crystal structure; Magnetic property;

A novel methoxide-bridged complex, (PyH)2[Mo2O3(OMe)(OOCCH3)Cl4], has been prepared. It converts readily to {Mo2O22-O)2}2+ species.Reaction of a mononuclear [MoOCl4(H2O)] with pyridinium acetate in methanol leads to formation of an unusual complex, (PyH)2[Mo2O3(OMe)(OOCCH3)Cl4]. Instead of the common dioxide-bridged structure, the anionic complex features a pair of metal centres bridged by oxide, methoxide and acetate. The Mo−Mo bond distance is 2.6390(2) Å. The intermediate nature of this triply-bridged species was shown by its reactions with pyridine and methanol which afforded stable {Mo2O22-O)2}2+ species.
Keywords: Polyoxometalates; Molybdenum(V) complexes; Methoxide; Acetate; Crystal structure;

Chromogenic sensing of Cu(II) by imino linked thiacalix[4]arene in mixed aqueous environment by Manoj Kumar; J. Nagendra Babu; Vandana Bhalla; Abhimanew Dhir (332-335).
Thiacalix[4]arene based imino receptors 45 carrying azophenol appendage have been synthesized and studied for their binding abilities towards different metal ions (Li+, Na+, K+, Cd2+, Ni2+, Cu2+, Zn2+, Ag+, Pb2+ and Hg2+). Receptor 4 showed selective chromogenic sensing for Cu2+ ions in mixed aqueous conditions (THF:H2O, 9:1 v/v).Thiacalix[4]arene based imino receptors 45 carrying azophenol appendage have been synthesized and studied for their binding abilities towards different metal ions (Li+, Na+, K+, Cd2+, Ni2+, Cu2+, Zn2+, Ag+, Pb2+ and Hg2+). Receptor 4 showed selective chromogenic sensing for Cu2+ ions in mixed aqueous conditions (THF:H2O, 9:1 v/v).
Keywords: Thiacalix; Chromogenic; Colorimetric; Cu2+ selective;

Syntheses, characterizations, and redox behaviors of new self-assembled metal complexes with bridging ligands incorporating chalcogen sites by Makoto Miyazawa; Yasuhiko Irie; Kazuki Kashimoto; Naoko Nishina; Mitsuru Kondo; Sachiko Yasue; Kenji Maeda; Fumio Uchida (336-339).
Self-assembled metal complexes were synthesized from organic bridging ligands incorporating chalcogen sites. Single-crystal X-ray diffraction analysis demonstrated that these metal complexes have network structures connected by coordination bonds, π–π interactions, and hydrogen bonds. Their crystal structures and redox properties based on the bridging ligands in the solid state are described.Three new complexes, [Zn(dbsf)2(dmf)2] · 5.5dmf (dbsf = 4,4′-sulfonyldibenzoate) (1 β ), [Cu(tdsa)(phen)2] · 1.5EtOH (tdsa = 5,5′-thiodisalicylate, phen = 1,10-phenanthroline) (2), and [Cu(sdp)(phen) · Cu(Hsdp)(phen)(CH3COO)] · 3EtOH (sdp = 4,4′-sulfonyldiphenolate) (3) were prepared and structurally characterized. Complex 1 β shows a one-dimensional coordination framework constructed from bridges between Zn(II) centers with two ligands. Complex 2 is a monomeric complex, which assembles by π–π interactions. Complex 3 shows a unique two-dimensional coordination framework that is constructed from two Cu(II) centers, sdp, and Hsdp. The redox properties of these three complexes were characterized by solid-state cyclic voltammetry. Complexes 1 β and 3 show irreversible reduction waves because of the reduction of their sulfone sites. Complex 2 shows an irreversible oxidation wave because of oxidation of the sulfide site.
Keywords: Coordination polymer; Redox property; Crystal structure; Chalcogen site;