Ag(I)-mediated in situ dehydrogenative coupling of 3-amino-1,2,4-triazole into 3,3'-azobis(1,2,4-triazole) in Cd(II) coordination polymers.

Ag(I)-mediated in situ generation of 3,3'-azobis(1,2,4-triazole) (AzTAZ) from 3-amino-1,2,4-triazole (AmTAZ) through dehydrogenative coupling has been realized during the crystallization process of two Cd(II) coordination polymers with novel topological architectures: a (3, 4, 5)-connected (4 x 6(2))(2)(4 x 6(7) x 8(2))(2)(6(5) x 10) net for [Cd(2)(AmTAZ)(2)(AzTAZ)](n) (1) and a 4-connected (6(2) x 8(4))(6(4) x 8(2))(6(5) x 8)(2) net for [Cd(AzTAZ)(2)(H(2)O)](n) (2), whereas AmTAZ retains its original form in a heterometallic complex, [Ag(2)Cd(AmTAZ)(4)](n) (3).

Temperature-controlled syntheses of substituted 1,2,4-triazolelead(II) complexes: active lone pair and N-H...X (X = Cl, Br, I) hydrogen bonds.

Three isomorphous lead(II) complexes with a new {N(3)SX}-coordinated (X = Cl, Br, I) mode have been synthesized and characterized by X-ray diffraction. The structural analyses reveal that the coordination environment around the center metal is distinctly influenced by the stereochemical 6s(2) lone pair and N-H...X hydrogen bonds. Additionally, doubly deprotonated trzS(2-) (HtrzSH = 1,2,4-triazole-3-thiol) generated in situ via deamination and dehydrazination of ahtrzS(-) (ahtrzSH = 4-amino-3-hydrazino-5-mercapto-1,2,4-triazole) was first observed in a semiconducting three-dimensional coordination network at higher reaction temperature.

Synthesis, structure, and luminescent properties of hybrid inorganic-organic framework materials formed by lead aromatic carboxylates: inorganic connectivity variation from 0D to 3D.

The hydro(solvo)thermal reactions of Pb(OAc)(2).3H(2)O with the aromatic carboxylic ligands 1,3,5-benzenetricarboxylic and 1,4-, 1,2-, and 1,3-benzenedicarboxylic acids (1,3,5-H(3)BTC; 1,4-, 1,2-, and 1,3-H(2)BDC) have yielded a family of inorganic-organic framework materials: [Pb(2)(1,3,5-BTC)(mu(3)-OH)(H(2)O)](n) (Iota), [NaPb(1,3,5-BTC)(H(2)O)](n) (IotaIota), [Pb(1,4-BDC)](n) (IotaIotaIota), [Pb(5)(1,2-BDC)(4)(OAc)(2)](n) (IV), and {[Pb(5)(1,3-BDC)(5)(H(2)O)(2)](2).H(2)O}(n) (V). These complexes have been characterized by means of single-crystal X-ray diffraction, X-ray powder diffraction, thermogravimetric analysis-mass spectrometry, and photoluminescence spectra. They are all three-dimensional structures except for two-dimensional IV. Topology analysis reveals that complexes I an V represent rare (4,8)-connected flu and (3,4)-connected zeolite-like nets, respectively. The five complexes exhibit diverse inorganic connectivity, including a 0D Pb(4)O(16) cluster for I, a 1D Pb-O-Pb chain for II, a 2D Pb-O-Pb network for III and IV, and an unprecedented 3D Pb-O-Pb framework for V. And the diversity in inorganic arrays leads to differences in luminescent properties of these complexes.

Breaking the mirror: pH-controlled chirality generation from a meso ligand to a racemic ligand.

To study the conversion from a meso form to a racemic form of tetrahydrofurantetracarboxylic acid (H(4)L), seven novel coordination polymers were synthesized by the hydrothermal reaction of Zn(NO(3))(2)6 H(2)O with (2S,3S,4R,5R)-H(4)L in the presence of 1,10-phenanthroline (phen), 2,2'-bipyridine (2,2'-bpy), or 4,4'-bipyridine (4,4'-bpy): [Zn(2){(2S,3S,4R,5R)-L}(phen)(2)(H(2)O)]2 H(2)O (1), [Zn(4){(2S,3R,4R,5R)-L}{(2S,3S,4S,5R)-L}(phen)(2)(H(2)O)(2)] (2), [Zn(2){(2S,3S,4R,5R)-L}(H(2)O)(2)]H(2)O (3), [Zn(4){(2S,3R,4R,5R)-L}{(2S,3S,4S,5R)-L} (2,2'-bpy)(2)(H(2)O)(2)]2 H(2)O (4), [Zn(2) {(2S,3S,4R,5R)-L}(2,2'-bpy)(H(2)O)] (5), [Zn(4){(2S,3R,4R,5R)-L}{(2S,3S,4S,5R)-L} (4,4'-bpy)(2)(H(2)O)(2)] (6), and [Zn(2) {(2S,3S,4R,5R)-L}(4,4'-bpy)(H(2)O)] 2 H(2)O (7). These complexes were obtained by control of the pH values of reaction mixtures, with an initial of pH 2.0 for 1, 2.5 for 2, 4, and 6, and 4.5 for 3, 5, and 7, respectively. The expected configuration conversion has been successfully realized during the formation of 2, 4, and 6, and the enantiomers of L, (2S,3R,4R,5R)-L and (2S,3S,4S,5R)-L, are trapped in them, whereas L ligands in the other four complexes retain the original meso form, which indicates that such a conversion is possibly pH controlled. Acid-catalyzed enol-keto tautomerism has been introduced to explain the mechanism of this conversion. Complex 1 features a simple 1D metal-L chain that is extended into a 3D supramolecular structure by pi-pi packing interactions between phen ligands and hydrogen bonds. Complex 2 has 2D racemic layers that consist of centrosymmetric bimetallic units, and a final 3D supramolecular framework is formed by the interlinking of these layers through pi-pi packing interactions of phen. Complex 3 is a 3D metal-organic framework (MOF) involving meso-L ligands, which can be regarded as (4,6)-connected nets with vertex symbol (4(5).6)(4(7).6(8)). Complexes 4 and 5 contain 2D racemic layers and (6,3)-honeycomb layers, respectively, both of which are combined into 3D supramolecular structures through pi-pi packing interactions of 2,2'-bpy. The structure of complex 6 is a 2D network formed by 4,4'-bpy bridging 1D tubes, which consist of metal atoms and enantiomers of L. These layers are connected through hydrogen bonds to give the final 3D porous supramolecular framework of 6. Complex 7 is a 3D MOF with novel (3,4,5)-connected (6(3))(4(2).6(4))(4(2).6(6).8(2)) topology. The thermal stability of these compounds was also investigated.

Controlled generation of acentric and homochiral coordination compounds from a versatile asymmetric ligand 4-(1H-1,2,4-triazol-3-yl)-4H-1,2,4-triazole.

Luminescent acentric and homochiral coordination compounds, which possess new topological networks, multiple helical structures and NLO properties, have been generated through the control of a versatile asymmetric ligand as well as inorganic anions, and this suggests a new protocol for preparing acentric and chiral materials.

Topology analysis and nonlinear-optical-active properties of luminescent metal-organic framework materials based on zinc/lead isophthalates.

Two 3D Zn(II) and Pb(II) isophthalates, [Zn(ip)]n (1) and [Pb4(mu4-O)(ip)3(H2O)]n (2) (H2ip = isophthalic acid), have been prepared under hydro(solvo)thermal conditions and characterized by single-crystal X-ray diffraction. The two complexes crystallize in different space groups (P4(3)2(1)2 for 1 and P2(1)/c for 2) and have different bridging modes of the ip ligand. The 3D framework of 1 is constructed by the interconnection of ZnO4 polyhedra via ip ligands, which represents a chiral net with PtS-type topology. In contrast, complex 2 is formed by the combination of Pb4O-cluster secondary building units and has a novel (3.4.5)(3(2).4(5).5(6).6(7).7(2)) topology, which is the first ever example of a (3,7)-connected net. Complex 1 displays a second harmonic generation efficiency of about 1.5 times that of KH2PO4. Optical properties and thermal stabilities of the two complexes have been studied. Additionally, the calculations of band structure and density of states of 1 have also been performed with the density functional theory method.

Organically templated metal-organic framework with 2-fold interpenetrated {3(3).5(9).6(3)}-lcy net.

A new organic cation templated Zn(II) complex (Et3NH)[Zn4(ip)3(bta)3] (, ip = isophthalate, Hbta = benzotriazole) which consists of plate-like Zn4(bta)3 units bridged by ip ligands is reported; it is the first example of a 6-connected uninodal {3(3).5(9).6(3)}-lcy net which has never been observed previously in MOFs but has been theoretically anticipated.

Synthesis, structure, and physical properties of a new anions-controlled Cd(II)-guanazole (3,5-diamino-1,2,4-triazole) hybrid family.

Nine members of a new anions-controlled Cd(II)-guanazole (3,5-diamino-1,2,4-triazole=Hdatrz) hybrid family, that is, [Cd3(datrz)6(H2O)2] (1), [Cd3(datrz)4F2] (2), [Cd5(datrz)4Cl4(OH)2] (3), [Cd5(datrz)4Br4(OH)2] (4), [Cd3(datrz)2(SO3)2].(H2O) (5), [Cd3(datrz)2(O2CMe)4] (6), [Cd(datrz)(O2CEt)] (7), [Cd(Hdatrz)(O2CtBu)2] (8), and [Cd(Hdatrz)2(H2Edta)] (9) have been synthesized by exploiting hydrothermal reactions of guanazole with suitable cadmium salts under appropriate reaction conditions. With effective control of inorganic or organic anions, the coordination diversity of the guanazole ligand in 1-9 manifests an unprecedented enrichment with five bridging modes varying from bidentate to quadridentate, two of which are first reported. Compound 1 is the first reported three-dimensional chiral complex constructed from the guanazole ligand which adopts a novel N1, N2, amino N-bridging mode. Halogen anions F-, Cl-, and Br- controlled compounds 2-4 are all three-dimensional, with their guanazole ligands possessing another novel quadridentate bridging mode. Sulfite anions controlled compound 5 displays a three-dimensional network with peculiar cage-like hexnuclear cadmium clusters. As for organic anions, low dimensional structures have been found for alkylcarboxylate anions MeCO2-, EtCO2-, and tBuCO2- controlled compounds 6, 7, and 8 (two-dimensional) and for H2Edta2- controlled compound 9 (zero-dimensional), and their guanazole ligands manifest low coordination numbers as well. These hybrid materials also present interesting structure-induced physical properties. The chiral compound 1 exhibits the second-order nonlinear optical properties at room temperature. Compounds 2-9 except 6 all exhibit photoluminescence of blue fluorescent emissions in the solid state at ambient temperature, which may be assigned to the intraligand pi-pi* transitions. Some structure related red or blue emission shifts have been investigated. Thermal studies show that most compounds of this study possess a high thermal stability.

New coordination motifs of melamine directed by N-H---X (X = Cl or Br) hydrogen bonds.

Unusual mu(2)- and mu(3)-coordination modes of melamine are found in two organic-inorganic hybrid copper halides, [Cu(2)Br(2)(MA)](n) (1) and [Cu(3)Cl(3)(MA)](n) (2) (MA = melamine), in which the MA ligand affords two N-heterocycle N atoms to link (Cu(2)Br(2))infinity stairs and serves as a novel mu(3) bridge to give a 3D framework, respectively.

catena-Poly[[diaquazinc(II)]-micro-4,4'-sulfonyldibenzoato-kappa2O:O'].

The title compound, [Zn(C(14)H(8)O(6)S)(H(2)O)(2)](n), is the first reported metal complex of the 4,4'-sulfonyldibenzoate anion. The structure comprises zigzag chains of alternating [Zn(H(2)O)(2)](2+) and sulfonyldibenzoate units, the central Zn and S atoms of which lie on crystallographic twofold axes. The Zn(II) centre occupies a strongly distorted tetrahedral environment [O-Zn-O = 83.30 (7)-136.19 (8) degrees], coordinated by the two water O atoms [Zn-O = 1.986 (2) A] and one O atom from each of two carboxylate groups [Zn-O = 1.9942 (19) A], with much longer contacts to the other O atoms of these carboxylates [Zn-O = 2.528 (2) A]. Hydrogen bonds between carboxylate O atoms and coordinated water molecules in adjacent chains lead to the formation of a three-dimensional network structure.

Poly[mu2-trans-1,2-di-4-pyridylethylene-kappa2N:N'-mu2-sulfato-kappa2O:O'-zinc(II)].

The title compound, [Zn(SO(4))(C(12)H(10)N(2))](n), features a layered structure based on [Zn(SO(4))](n) spirals linked by 1,2-di-4-pyridylethylene (bpe) ligands, with the tetrahedral Zn and S atoms lying on twofold axes. The bpe ligands are centrosymmetric. The layers are linked by weak C-H...O interactions.

[Glottic measurement and vocal evaluation after three surgical techniques in the treatment of bilateral vocal cord paralysis].

OBJECTIVE: To evaluate postoperative glottic area and vocal quality of three various surgical techniques for treating bilateral vocal cord paralysis, including laser arytenoidectomy (Group A, 24 cases), reinnervation of the posterior cricoarytenoid muscle by phrenic nerve (Group B, 9 cases) and arytenoidectomy accompanying lateral cordopexy by extralaryngeal approach (Woodman's procedure, Group C, 13 cases). METHODS: 46 cases suffered from bilateral recurrent laryngeal nerve injury were included in our study. The pre-postoperative glottic measurement and vocal acoustic parameters were analyzed. RESULTS: The decannulated cases in group A and group B and group C were 22, 8, 13 respectively. The post-operative mean maximal glottic area was (47.2 +/- 7.4) mm2, (78.3 +/- 16.0) mm2, (48.1 +/- 6.5) mm2 respectively. Group B cases glottic area was larger than that of group A and group C (t value were 4.46 and 3.85, P value were 0.000 and 0.001). No significant difference was found between group A and group C (t = 1.68, P = 0.101). After surgery, in group A, 17 cases voice quality was the same compared with that of before surgery, and 7 cases voice quality had become worse; In group B, the voice quality had become better in 5 cases, completely recovered in 1 case, and had not change in 3 cases; In group C, the voice quality had become deteriorated in 10 cases and no change in 3 cases. And in group B, ipsilateral diaphragm paralysis in 9 cases after surgery, whose vital capacity and forced vital capacity had decreased to 72%-84%, 76%-84% of that before the surgery respectively; and the diaphragm mobility had recovered by 35%-76% respectively, while vital capacity and forced vital capacity had become 93%-97%, 91%-98% of that before the surgery. In Group B, all cases' pulmonary function was normal half a year postoperatively. CONCLUSIONS: Reinnervation of the posterior cricoarytenoid muscle by phrenic nerve seems to be best procedure with better post-operative voice and larger glottic area. Although the sufficient airway for decannulation can be acquired in Group A and Group C, but most of patients in Group A had pre-operative vocal level and badly abnormal in Group C.

[Endonasal anatomy of lacrimal sac and its clinical significance in dacryocystorhinostomy].

OBJECTIVE: To explore the intranasal surface localization of the lacrimal sac in endoscopic dacryocystorhinostomy. METHODS: Fifteen adult cadavers (30 sides) were studied, the data of projection position of the lacrimal sac on the lateral wall of nasal cavity were measured. RESULTS: In 2/3 cadavers, the lacrimal sac is located above the axilla of the middle turbinate, and 1/3 lies below it. A majority of the lacrimal sac (2/3) are located below the entry point of the common lacrimal canaliculus, about 1/3 lies above it. Inner canthal ligament projects on the middle of the lacrimal sac, almost equal to the level of common lacrimal canaliculus. Thirty-two cases (thirty-nine sides) of chronic dacryocystitis were followed-up > 6 months after operation. Thirty-five sides were cured, 2 sides improved and 2 sides ineffective. The cure rate was 89.8%, improve rate 5.1% and ineffective rate 5.1%, respectively, and the total effective rate was 94.9%. CONCLUSIONS: The central position of dacryocystorhinostomy should be 0.2 cm above the front of the axilla of the middle turbinate, to make an curved mucous membrane incision 0.8 cm above and 0. 4 cm below the front of the axilla of the middle turbinate and bone ostium about 1.2 cm x 1.0 cm. It is the best position in endoscopic dacryocystorhinostomy. Locating the inner canthal ligament with a bayonet type forceps to find the projection of lacrimal sac is also a simple and easy method.

Two cobalt(II) 5-aminoisophthalate complexes and their stable supramolecular microporous frameworks.

Two stable supramolecular microporous cobalt(II) polymers, namely [Co(HAIP)2]n.3nH2O (1) and [Co(AIP)(H2O)]n (2), AIP = 5-aminoisophthalate, were hydrothermally synthesized and characterized by single-crystal X-ray diffraction, IR spectra, thermogravimetric analyses, and variable-temperature magnetic susceptibility measurements. The two complexes are constructed from the same Co2(CO2)2 SBU, which is extended into a 1D chain in 1 and a 2D layer in 2. As a result, 1 and 2 are 2D and 3D coordination polymers, respectively. The 3D supramolecular network of complex 1 is held up by strong hydrogen bonds formed between carboxylate groups and shows very high stability when the free H2O molecules are removed, indicating an extraordinarily stable H-bonding system. Upon water ligands being liberated, complex 2 becomes a stable microporous solid with coordination-unsaturated Co centers. The behavior of the susceptibility curve of 1 suggests the occurrence of an interesting intrachain antiferromagnetic coupling between the Co(II) ions and the presence of a significant orbital contribution, whereas the features of 2 indicate an antiferromagnetic coupling with T(N) = 3.5 K and a long-range antiferromagnetic order with a field-induced magnetic transition.

A polar luminescent Zn polymer containing an unusual noninterpenetrated utp net.

A new Zn coordination polymer with the mixed ligands of 1,3,5-benzenetricarboxylate and 1,3-bis(4-pyridyl)propane has been hydrothermally synthesized, and an unusual distorted noninterpenetrated utp [or (10,3)-d] net has been defined.

A 3-D noninterpenetrating diamondoid network of a decanuclear copper(I) complex.

The solvothermal reaction of CuCl(2).2H(2)O with pyridine-4-thiol and ethanol yielded a novel photoluminescent 3-D polymeric complex with an interesting decorated diamondoid network that is constructed of decanuclear copper(I) cluster units and mu(4)-Cl ligands. The in situ generation of CuSO(4).5H(2)O implies the spontaneous occurrence of desulfurization and redox reactions in the present system.

Poly[[diaquacobalt(II)]-mu-4,4'-bipyridine-kappa2N:N'-mu-p-phenylenebis(oxyacetato)-kappa2O:O'].

The title compound, [CoII(C10H8O6)(C10H8N2)(H2O)2]n, was obtained by the hydrothermal reaction of CoSO(4) with benzene-1,4-dioxydiacetate [systematic name: p-phenylenebis(oxyacetate)] and 4,4'-bipyridine (4,4'-bpy). The Co atom lies at an inversion center and the benzene-1,4-dioxydiacetate and 4,4'-bipyridine moieties lie about other inversion centers. The benzene-1,4-dioxydiacetate ligands bridge the octahedral Co(II) coordination centers, forming a one-dimensional zigzag chain. The chains are further bridged by 4,4'-bpy ligands, forming a novel two-dimensional supramolecular architecture. Hydrogen-bonding interactions between the coordinated water molecules and the carboxylate O atoms lead to the formation of a three-dimensional network structure.