Syntheses,crystal structures and properties of two cadmium coordination polymers containing bis (2-methylimidazol-1-yl)methane(2-mBIM) and bis (imidazol-1-yl)methane (BIM) ligands

Coordination polymers, {[Cd(2-mBIM)₃](ClO₄)₂} _n (1) and [Cd(BIM)₂(NO₃)₂] _n (2), have been prepared from the reaction of bis(2-methylimidazol-1-yl)methane(2-mBIM) with Cd(ClO₄)₂ and bis(imidazol-1-yl)methane (BIM) with Cd(NO₃)₂ in ethanol and water, respectively. Their structures were characterized by single crystal X-ray diffraction and IR spectroscopy. Compound 1 crystallizes in the rhombohedral space group R-3c with a = b = 12.3617(5) Å, c = 38.896(3) Å, γ = 120°, V = 5147.5(5) ų, z = 6. The Cd^II occupies a crystallographic inversion center and is coordinated by six N atoms from six distinct 2-mBIM ligands to form a slightly distorted octahedral geometry. Each 2-mBIM is coordinated to two Cd^II cations, linking alternatively four Cd^II cations, resulting in a 32-membered M₄L₄ macrometallacycle. Compound 2 crystallizes in the monoclinic space group C2/m with a = 14.400(3) Å, b = 9.3894(18) Å, c = 8.6926(17) Å, β = 123.499(2)°, V = 980.1(3) ų, z = 2. The Cd coordinates to four nitrogen atoms from four different BIM and two nitrates to form a slightly distorted octahedral geometry. The BIM ligands bridge to form a 1-D infinite double-bridged chain structure with 16-membered M₂L₂ macrometallacyclic structural units.     

Dinuclear copper(II) complex and 1-D copper(II) complex with taurine Schiff base: synthesis,crystal structure,and properties

A dinuclear copper(II) compound, [Cu(btssb)(H₂O)]₂ · 4(H₂O) (1), and a 1-D chain copper(II) compound, [Cu(ctssb)(H₂O)] _n (2) [where H₂btssb is 2-[(5-bromo-2-hydroxy-benzylidene)-amino]-ethanesulfonic acid and H₂ctssb is 2-[(3,5-dichloro-2-hydroxy-benzylidene)-amino]-ethanesulfonic acid], were prepared and characterized. Compound 1 crystallizes in the monoclinic space group P2₁/c, with a = 10.109(2) Å, b = 20.473(4) Å, c = 6.803(1) Å, β = 100.32(3)°, V = 1385.1(5) ų, and Z = 2; R ₁ for 1796 observed reflections [I > 2σ(I)] was 0.0357. The geometry around each copper(II) can be described as slightly distorted square pyramidal. The Cu^II ··· Cu^II distance is 5.471(1) Å. Compound 1 formed a 1-D network through O–H ··· O hydrogen bonds and 1-D water chains exist. The 1-D chain complex 2 crystallizes in the triclinic space group P 1, with a = 5.030(2) Å, b = 7.725(2) Å, c = 17.011(5) Å, α = 92.706(4)°, β = 97.131(4)°, γ = 102.452(3)°, V = 638.6(3) ų, and Z = 2; R ₁ for 1897 observed reflections [I > 2σ(I)] was 0.0171. In 2, Cu(II) was also a slightly distorted square pyramid formed by two oxygens and one nitrogen from ctssb, one oxygen from another ctssb, and one water molecule. The complex formed a 1-D chain through O–S–O bridge of ctssb ligand. The 1-D chain further constructed a double chain through O?H ··· O hydrogen bonds.     

Bridging chlorides and hydroxides: syntheses and crystal structures of binuclear and tetranuclear NiII complexes derived from a reduced Schiff-base ligand 2-(2-pyridylmethylamino)ethanesulfonic acid

Two complexes, [Ni(pmt)(Cl)] (1) and [Ni₄(pmt)₄(OH)₄]·8H₂O (2) [Hpmt = 2-(2-pyridylmethylamino)ethanesulfonic acid], were synthesized by different experimental methods in methanol-water mixed solution. Compound 1 crystallizes in triclinic, space group P?1 with unit cell parameters: a = 8.315(2) Å, b = 8.383(2) Å, c = 9.128(2) Å, α = 103.654(2)°, β = 98.125(2)°, γ = 113.154(2)°, V = 548.6(2) ų, Z = 2. A pair of chlorides is μ ₂-bridges linking two Ni^II atoms in forming binuclear complex 1. The coordination environment at Ni^II is distorted square-pyramidal geometry. Compound (2) belongs to monoclinic, space group C2/c, with a = 16.5168(15) Å, b = 18.3718(17) Å, c = 17.5473(16) Å, α = γ = 90°, β = 93.3820(10)°, V = 5315.3(8) ų, Z = 4. Four hydroxides are μ ₃-bridges joining four Ni^II atoms to generate a cubic framework as a tetranuclear complex. The configuration at each Ni^II is distorted octahedral. Both π–π stacking of pyridine rings and intermolecular hydrogen bonds stabilize the solid state structures for 1 and 2.     

Synthesis of 2-D graphite-like and 3-D diamond-like silver(I) polymers with 1,3-imidazolidine-2-thione

Two metal–organic coordination polymers, [Ag₂(imdt)₃(OAc)₂] _n (1) (imdt = 1,3-imidazolidine-2-thione, OAc = CH₃COO^?) and [Ag(imdt)Cl] _n (2), were synthesized under similar conditions by using Et₃N (triethylamine) as buffering agent. X-ray diffraction shows that 1 crystallizes in the monoclinic system, C2 /c space group, a = 13.822(5) Å, b = 9.082(3) Å, c = 16.965(6) Å, V = 2114.2(14) ų, Z = 8, D _c = 2.012 g cm^?3. Compound 2 crystallizes in the orthorhombic system, P2₁2₁2₁ space group, a = 7.993(6) Å, b = 7.993(6) Å, c = 10.548(7) Å, V = 673.9(7) ų, Z = 4, D _c = 2.419 g cm^?3. Both 1 and 2 exhibit different architectures due to their different anions. Compound 1 shows a 2-D graphite-like network structure and 2 shows a 3-D diamond-like network structure.     

Synthesis,crystal structure and magnetic properties of a dinuclear manganese(III) tetradentate Schiff-base complex

A dinuclear manganese(III) tetradentate Schiff-base complex, [Mn₂(salophen)₂(4,4′-bipy)₃](BPh₄)₂ (1) (salophen = N,N′-o-phenylene-bis(salicylideneaminato)), has been synthesized and structurally characterized. Compound 1 crystallized in the triclinic, P 1 space group, a = 13.431(4), b = 13.791(4), c = 13.886(4) Å, α = 73.599(5)°, β = 80.410(6)°, γ = 71.241(5)°, V = 2328.3(12) ų. Complex 1 contains two Mn(salophen) moieties bridged by 4,4′-bipy to form a dinuclear unit, with two terminal 4,4′-bipy ligands. Variable temperature magnetic susceptibility (2–300 K) shows very weak ferromagnetic interactions between the Mn(III) ions.     

Synthesis,crystal structure and luminescence of a 3-D coordination polymer based on 4-(1H-tetrazol-5-yl) benzoic acid

A cobalt(II) coordination polymer [Co(4-TZBA^2?)(H₂O)₂] (1) was obtained by treatment of Co(ClO₄)₂ · 6H₂O with 4-(1H-tetrazol-5-yl)benzoic acid [H₂(4-TZBA)] under hydrothermal conditions. The X-ray single crystal diffraction analysis reveals that 1 crystallizes in monoclinic P2₁/c, with a = 10.503(2) Å, b = 9.0860(18) Å, c = 10.179(2) Å, β = 96.75(3)° and Z = 4. In 1, adjacent cobalt(II) atoms are bridged by two 4-TZBA^2? ligands to form a dimer, which is linked with six dimers to result in a 3-D structure. 1 exhibits strong luminescence at room temperature in the solid state.     

Syntheses and crystal structures of two cadmium coordination polymers [Cd(2-mBIM)(NCS)(SCN)] n and [Cd2(2-mBIM)2(NO3)2(C4H4O4)(H2O)5] n based on bis(2-methylimidazol-1-yl)methane

Two cadmium(II) coordination polymers, [Cd(2-mBIM)(NCS)(SCN)] _n (1) and [Cd₂(2-mBIM)₂(NO₃)₂(C₄H₄O₄)(H₂O)₅] _n (2) (2-mBIM = bis(2-methylimidazo-1-yl)methane, C₄H₄O₄= succinate), have been synthesized and characterized by X-ray diffraction. Complex 1 crystallizes in the triclinic space group P 1 with a = 9.0770(5) Å, b = 9.4043(4) Å, c = 19.8720(9) Å, α = 101.551(1)°, β = 93.498(1)°, γ = 108.484(1)°, V = 1562.02(13) ų, and Z = 2. Each Cd(II) is octahedrally coordinated and connected with two adjacent Cd(II)'s by double end-to-end thiocyanate bridges, resulting in the formation of 1-D zigzag chains, linked to each other via bridging 2-mBIM giving a 2-D supramolecular framework. Complex 2 crystallizes in the monoclinic space group P2(1)/n with a = 12.6543(6) Å, b = 7.7128(4) Å, c = 17.3089(9) Å, β = 109.3980(10)°, V = 1593.45(14) ų, and Z = 2. Cd(II) is coordinated with oxygen and nitrogens from two independent 2-mBIM, in a cis-configuration to form a 1-D helical structure. A 3-D supramolecular network comprised of succinate anion bridged 1-D helical chains, and weak hydrogen bonds between dimer waters gave 2-D layers.     

Synthesis,crystal structure,magnetic property,and nuclease activity of a binuclear iron(III) complex

A μ-oxo-di-μ-carboxylato-bridged iron(III) complex containing two tridentate nitrogen ligands, {[Fe₂(bpma)(bpea)(μ-CH₃COO)₂ μ-O)] · (ClO₄)₂ · 0.5CH₃OH} (1) (bpma = N, N-bis(2-pyridylmethyl)methyl-amine, bpea = N,N-bis(2-pyridylmethyl)ethylamine), has been synthesized and determined by X-ray diffraction. Complex 1 crystallizes in the monoclinic space group P2₁/c with a = 10.9434(12) Å, b = 23.118(3) Å, c = 15.8721(18) Å, β = 92.736(2)° and Z = 4. In 1, each Fe(III) has a distorted octahedral geometry with a N₃O₃ donor set. The Fe(III) atoms are bridged by two carboxyl groups and one μ-oxo oxygen with Fe1–Fe2 separation of 3.064 Å. Susceptibility data of 1 indicate strong intramolecular antiferromagnetic coupling of the high-spin Fe(III) atoms with J = ?121.0 cm^?1 and g = 2.04. The interaction with calf thymus DNA was investigated by UV absorption and fluorescent spectroscopy. Results show that the complex binds to ct-DNA with a moderate intercalative mode. The interaction between 1 and pBR322 DNA has also been investigated by submarine gel electrophoresis; the complex exhibits effective DNA cleavage activity in the absence of activating agents under similar physiological conditions.     

Cobalt(II) Complexes with Dicyanamide — from Binuclear Entities to Chains

One binuclear complex [Co(bpm*)₂(dca)]₂(ClO₄)₂ ( 1 ) and two 1D chain Co^II complexes, {[Co(bpm)₂(dca)](ClO₄)}_n ( 2 ) and [Co(dmf)₂(dca)₂]_n ( 3 ), (bpm*: bis[(3, 5‐dimethyl)pyrazolyl]methane; bpm: bis(pyrazolyl)methane; dca: dicyanamide; dmf: N, N‐dimethyl formamide) have been prepared and structurally characterized. The cobalt atoms are hexa‐coordinated forming a slightly distorted octahedral coordination. Compound 1 crystallizes in the monoclinic system, space group P2₁/c, a = 9.849(3)Å, b = 21.944(7)Å, c = 13.814(5)Å, β = 94.824(6), Z = 4, R₁ = 0.0672, wR₂ = 0.1395. 1 is a binuclear complex linked by two dca ligands, and each Co^II ion is coordinated by two terminal bpm* ligands. Compound 2 crystallizes in the orthorhombic system, space group Cmcm, a = 10.377(4)Å, b = 13.594(5)Å, c = 15.999(6)Å, Z = 4, R₁ = 0.0609, wR₂ = 0.1328. The structure of 2 can be described as a one‐dimensional zigzag chain of Co^II ions bridged by one dca ligand. Each Co^II ion in the chain is coordinated by two bpm ligands. Compound 3 crystallizes in the monoclinic system, space group C₂, a = 13.559(15)Å, b = 7.393(8)Å, c = 8.110(9)Å, β = 112.228(15), Z = 2, R₁ = 0.0260, wR₂ = 0.0760. 3 has a one‐dimensional linear chain of Co^II ions bridged by two dca ligands, in which each Co^II ion is coordinated with two dmf molecules.     

Ru(II) COMPLEXES CONTAINING CHELATING PHOSPHINE LIGANDS. SYNTHESIS,CHARACTERIZATION, AND X-RAY CRYSTAL STRUCTURES OF DICHLOROBIS(1,2-BIS(DIPHENYLPHOSPHINO)ETHANE)Ru(II) AND THE COORDINATIVELY UNSATURATED TRIGONAL-BIPYRAMIDAL CATION,CHLOROBIS-(1,2-BIS(DIPHENYLPHOSPHINO)ETHANE)Ru(II)

Abstract

The reaction of trans-RuCl₂(dppe)₂ (1), with AgBF₄ in tetrahydrofuran leads to abstraction of one of the halide ligands to produce the trigonal-bipyrimidal complex, [RuCl(dppe)₂]BF₄ (2). Both products are characterized by ³¹P NMR spectroscopy and their crystal structures determined. For the coordinatively unsaturated trigonal-bipyramidal complex (2), we found no evidence for the presence of more than one species or fluxional behaviour at room temperature in the ³¹P NMR spectrum. This complex was found to possess a trigonal-bipyramidal geometry in the solid state. Crystals of 1 are monoclinic, space group P2₁/c with a = 23.713(4)Å, b=11.156(1)Å, c = 17.595(2)Å, β=103.23(1) and v=4531(1)ų. Convergence to conventional R values of R=0.043 and R_w = 0.042 was obtained for 416 variable parameters and 2746 reflections with I>3σ(I). Compound 2 in triclinic, P1, a=12.482(3)Å, b=12.543(3)Å, c=17.582(3)Å, α = 87.52(2)°, β= 72.70(2)° γ = 74.35(2)° and V= 2529(1)ų. Values of R = 0.072 and R_w = 0.097 were obtained for 487 variable parameters and 3242 reflections with I>3σ(I)     

A 3-D cobalt(II)-coordination polymer with mixed-connected network topology constructed from 4-pyridin-3-yl-benzoic acid

A new coordination polymer, [Co₂(μ-H₂O)(4,3-pybz)₄] _n (1), has been hydrothermally synthesized from Co(NO₃)₂ · 6H₂O and an unsymmetrical 4-pyridin-3-yl-benzoic acid (4,3-Hpybz), which is characterized by IR, elemental analysis, thermogravimetric analysis, and single crystal X-ray diffraction. This compound crystallizes in monoclinic, space group C2/c with a = 11.876(3) Å, b = 15.462(3) Å, c = 21.545(4) Å, β = 94.873(5)°, V = 3942.0(15) ų, Z = 4, Dc = 1.565 g cm^?3, F(000) = 1904, GOF = 1.025, μ = 0.910 mm^?1, R ₁ = 0.0456, wR ₂ = 0.0983. Compound 1 shows a 3-D (3,6)-connected coordination framework with (3.4.5)(3².4⁴.5⁵.6².7²) topology, in which cobalt is a six-connected node, and the 4,3-Hpybz ligands serve as two-connected spacers and three-connected nodes. In addition, the magnetic and thermal properties of 1 have also been investigated.     

SYNTHESES,CHARACTERIZATION AND CRYSTAL STRUCTURE OF TETRAMETHYLDIBENZOTETRAAZA[14]-ANNULENE ZINC(II) COMPLEXES CONTAINING AN AXIAL BASE

Abstract

The complexes of Zn(tmtaa) and Zn(tmtaa)L [H₂tmtaa = tetramethyldibenzotetraaza[14]-annulene; L = triethylamine, pyridine (Py) and p-dimethylaminopyridine (p-N(CH₃)₂Py)] were synthesized and characterized by IR, LTV, mass and NMR spectra as well as DSC measurements. The effects of different axial ligands (L) on the spectral properties of the complexes have been studied. The crystal structure of Zn(tmtaa)N(C₂H₅)3 was determined by X-ray diffraction. The crystal belongs to a monoclinic system and the space group is P2₁/n. The cell parameters are a = 11.134(2)A, b = 17.453(4)Å, c= 13.784(3)Å, ? = 106.19(3)°, Z = 4, R₁, =0.0336 and wR₂= 0.0805 for 4539 independent reflections with I <2σ(I). The zinc(II) is coordinated through four nitrogen atoms of tmtaa and a nitrogen of triethylamine to form a five-coordinate square-pyramidal structure. The average bond length of Zn for the four nitrogens of tmtaa is 2.050(2)Å and for a nitrogen of triethylamine is 2.188(2)Å. The displacement of the zinc to the plane of four nitrogens of tmtaa is 0.563(2)Å.     

Synthesis and Characterization of Three Homoleptic Bismuth Silanolates: [Bi(OSiR3)3] (R = Me,Et, iPr)

The bismuth tris(triorganosilanolates) [Bi(OSiR₃)₃] ( 1 , R = Me; 2 , R = Et; 3 , R = iPr) were prepared by reaction of R₃SiOH with [Bi(OtBu)₃]. Compound 1 crystallizes in the triclinic space group with Z = 2 and the lattice constants a = 10.323(1) Å, b = 13.805(1) Å, c = 21.096(1) Å and α = 91.871(4)°, β = 94.639(3)°, γ = 110.802(3)°. In the solid state compound 1 is a trimer as result of weak intermolecular bismuth‐oxygen interactions with Bi–O distances in the range 2.686(6)–3.227(3) Å. The coordination at the bismuth atoms Bi(1) and Bi(3) is best described as 3 + 2 coordination whereas Bi(2) shows a 3 + 3 coordination. The intramolecular Bi–O distances fall in the range 2.041(3)–2.119(3) Å. Compound 3 crystallizes in the orthorhombic space group Pbcm with Z = 4 and the lattice constants a = 7.201(1) Å, b = 23.367(5) Å and c = 20.893(1) Å, whereas the triethylsilyl‐derivative 2 is liquid. In contrast to [Bi(OSiMe₃)₃] ( 1 ) compound 3 is monomeric in the solid state, but shows similar intramolecular Bi–O distances in the range 1.998(2)–2.065(5) Å. The bismuth silanolates are highly soluble in common organic solvents and strongly moisture sensitive. Compound 1 shows the lowest thermal stability.     

Syntheses,crystal structures,and spectroscopic properties of copper(II) complexes with 3,14-diethyl-2,6,13,17-tetraazatricyclo(16.4.0.07,12)docosane

[Cu(L)(NO₃)₂] (1) and [Cu(L)(H₂O)₂](SCN)₂ (2) [L?=?3,14-diethyl-2,6,13,17-tetraazatricyclo(16.4.0.0^7,12)docosane] have been prepared and structurally characterized by single-crystal X-ray diffraction at 100?K. For these constrained macrocycle complexes, copper(II) exists in a tetragonally distorted octahedral environment with the four nitrogen atoms of the macrocyclic ligands and two oxygen atoms from either nitrate or water in axial positions. The macrocyclic ligands in both complexes adopt the most stable trans-III conformation. The Cu–N distances are 2.021(2)–2.047(2)?Å and typical but the axial ligands are weakly coordinating, with Cu–O bond lengths, 2.506(2)?Å for 1 and 2.569(2)?Å for 2, due to the pseudo Jahn–Teller effect. The crystals are stabilized by a 3-D network by intra and intermolecular hydrogen bonds that are formed among the secondary nitrogen hydrogen atoms and nitrate in 1, and intermolecular hydrogen bonds are formed by water and thiocyanates in 2. The electronic absorption and IR spectral properties are also discussed.     

Cu(I) cloride complexes with 4,5-(2-pyridylethylene)dithio-1,3-dithiol-2-thione and triphenylphosphine

Heteroligand binuclear complexes of CuCl with triphenylphosphine and 5-pyridine-2-yl-5,6-dihydro-[1,3]dithiolo[4,5-b][1,4]dithiine-2-thione (L¹) of the compositions [CuCl(PPh₃)(L¹)]₂ (I) and [CuCiL¹]₂ (II) are synthesized and studied by X-ray diffraction method. Crystals I are monoclinic; space group P2₁/n, a=8.9520(18) Å, b=18.926(4) Å, c=16.841(3) Å, β=94.96(3)°, Z=2. The Cu(I) atom has a quasi-tetrahedral surrounding involving the tetraphenylphosphine P atom, the pyridyl N atom of the molecule L¹, and two bridging Cl atoms. Crystals II are monoclinic; space group P2₁/c, a=9.3520(19) Å, b=8.1490(16) Å, c=18.660(4) A, β = 104.43(3)°, Z = 2. Both L¹ ligands in complex II act as bridges. The Cu(I) atom also has a quasi-tetrahedral surrounding formed by the Cl atoms, the pyridyl N atoms and thiol S atom of one L¹ ligand, and the thione S atom of the second L¹ ligand. Similar binuclear complexes with the bridging function of the L¹ ligand were also detected in a solution of II by the ESI method.     

SYNTHESIS AND STRUCTURES OF DICHLOROTETRAKIS-(PHENYLTHIOUREA) CADMIUM(II) AND CATENA-BIS(THIOCYANATE) BIS(PHENYLTHIOUREA)CADMIUM(II)

Abstract

Two new cadmium(II) complexes with phenylthiourea (PTU), namely Cd(PTU)₄Cl₂ (1) and [Cd₂(NCS)₂(μ₂-SCN)₂(PTU)₂(μ₂-PTU)₂] _n (2), have been prepared and characterized structurally by X-ray diffaction. Complex 1 crystallizes in the monoclinic space group C2/c, with a = 27.057(13), b = 8.108(3), c = 16.751(8) Å, β = 114.46°, V = 3345(3) ų, Z = 4. Complex 2 crystallizes in the triclinic space group P-1, with a = 9.336(3), b = 14.686(5), c = 16.911(5) Å, α = 71.36(2), β = 84.31(2), γ = 72.470(10)°, V = 2095.0(12) ų Z = 4. The structural analysis shows that each metal atom in both the mononuclear complex 1 and polynuclear complex 2 is octahedrally coordinated by four sulfur atoms and two chloro ligands or two nitrogen atoms from the thiocyanate groups, respectively. The PTU ligand can serve as either a monodentate ligand or a μ₂-bridging ligand upon coordination to a metal atom.     

Rhenium(I) Tellurolate,Telluroether and Bidentate-Telluroether Complexes: Crystal Structures of Re(CO)3Br(PhTe(CH2)3TePh), PhTeRe(CO)5 Re2(μ-SePh)2(CO)8 and [(PhTeMe)Re(CO)5][BF4]

The monomeric rhenium(I) complex with bidentate telluroether ligand Re(CO)₃Br(PhTe(CH₂)₃TePh) (1) was accessible via reaction of the PhTe(CH₂)₃TePh with Re(CO)₅Br. This chelate complex crystallized in triclinic space group $ {\rm P}\bar 1 $ with a = 9.390(5) Å, b = 10.961(3) Å, c = 11.849(4) Å a = 63.30(3)°, β = 87.49(4)° γ = 69.31(4)°, V = 1009.5(7) ų Z = 2, R = 0.033, and R_w = 0.034. Reaction of Re(CO)₅Cl with NaTePh yielded the Re(I) specics PhTeRe(CO)₅ (2). This complex crystallized in triclinic space group $ {\rm P}\bar 1 $ with a = 7.085(1) Å, b = 9.203(1) Å, c = 11.341(1) Å, α = 107.24(1)°, β = 100.56(1)°, γ = 96.47(1)°, V = 683.2(2) ų, Z = 2, R = 0.027, R_w = 0.022. Reaction of PhTeRe(CO)₅ and (PhSe)₂ in THF at 65 °C yielded a product that was confirmed crystallographically to be the known species Re₂(μ-SePh)₂(CO)₈ (3), in which two phenylselenolate ligands bridge the two Re(I). Compound 3 crystallized in monoclinic space group P2₁/n with a = 7.210(2) Å, b = 18.862(6) Å, c = 9.083(3) Å, β = 107.48(3)° V = 1178.2(7) ų, Z = 2, R = 0.046, and R_w = 0.051. Methylation of PhTeRe(CO)₅ with [Me₃O][BF₄] afforded Re(I) product [(PhTeMe)Re(CO)₅][BF₄] (4). This monodentate telluroether species crystallized in monoclinic space group P2₁/n with a = 8.405(1) Å, b = 13.438(3) Å, c = 15.560(2) Å, β = 92.59(1)° V = 1755.5(5) ų, Z = 4, R = 0.035, and R_w = 0.035.     

Hydrothermal synthesis,crystal structures,and blue photoluminescence of two 2-D Ag–1,2,4-triazolate coordination polymers with 4462 topology

Two 2-D metal-organic coordination polymers, {[Ag(NH₂–BPT)] · NO₃} _n (1) and {[Ag(BPT)] · H₂O} _n (2), have been synthesized via self-assembly of AgNO₃ and 4-amino-3,5-bis(3-pyridyl)-1,2,4-triazole (NH₂–BPT) under hydrothermal conditions by controlling the reaction temperatures. Lower reaction temperature (140°C) led to formation of 1, which crystallizes in the monoclinic system, space group C2/c, a = 24.001(3), b = 15.844(2), and c = 12.981(3) Å, V = 2996.8(6) ų, Z = 8. When the temperature was increased to 180°C, in situ deaminization of the organic ligand led to crystallization of 2 (space group P₂1 /n, a = 7.3106(10), b = 19.633(2), and c = 9.0596(16) Å, V = 1190.2(3) ų, Z = 4). The NH₂–BPT in 1 and BPT in 2 are μ₄ tetradentate utilizing two triazolyl and two pyridyl nitrogens, generating an unusual 2-D layer, in which binuclear Ag(I) motifs and organic ligands are four-connecting nodes that inter-link in 4⁴6² topology. Adjacent 2-D metal-organic layers are linked by a system of hydrogen bonds to form 3-D supramolecular frameworks. Strong blue fluorescence emissions are observed for 1 and 2 in the solid state at ambient temperature.     

Synthesis and Structural Characterization of [Cu20Se4(μ3‐SePh)12(PPh3)6] and [Ag(SePh)]∞

Reaction of lithium phenylselenothiolate, generated in situ from the reductive cleavage of PhSe‐SiMe₃ with alkyl lithium reagents and insertion of elemental sulfur, with triphenylphosphine solubilized CuCl affords the molecular cluster complex [Cu₂₀Se₄ (μ₃‐SePh)₁₂(PPh₃)₆] ( 1 ). The analogous reaction with AgCl yields the extended structure [Ag(SePh)]_∞ ( 2 ) in which an infinite layer of Ag^I atoms is capped on either side by μ₄‐SePh ligands. 1: space group P¯1, a = 17.9510(6), b = 18.1712(7), c = 31.4311(11) Å, a = 78.098(2), β = 82.905(2), γ = 70.012(2)°. 2: space group C2/c, a = 5.8762(6), b = 7.2989(7), c = 29.124(2) Å, β = 95.790(3)°.     

A (3,9)-connected cadmium 1,2,4-triazolate framework based on a trinuclear inorganic cluster

Hydrothermal reaction of 1,2,4-triazole with CdCl₂?·?2.5H₂O generated a 3-D metal-organic framework, {[Cd₃Cl₂(Trz)₄]?·?H₂O} _n (1) (Trz?=?1,2,4-triazole), which was characterized by elemental analysis, FT-IR, X-ray powder diffraction, X-ray single-crystal diffraction, TG/DTA, and photoluminescence measurements. Compound 1 crystallizes in the orthorhombic system, space group Pnma, a?=?16.906(3)?Å, b?=?8.3151(17)?Å, c?=?13.080(3)?Å, V?=?1838.6(6)?ų, Z?=?4. Cd(1) is coordinated by four nitrogen atoms and one chloride to form a distorted trigonal-bipyramidal geometry. Cd(2) is an octahedron defined by four triazole nitrogen atoms and two chlorides. Two Cd(2) and one Cd(1) are linked by μ ₃-Cl(1) to give a [Cd₃Cl] cluster, which is connected by μ ₂-Cl(2) to generate a 1-D inorganic chain. The 1-D inorganic chains are extended by μ ₃-Trz to form a 2-D hybrid layer in the b, c-plane, which is ultimately linked by residual triazole ligands to give a 3-D framework. The [Cd₃Cl] clusters and the Trz ligands can be regarded as 9- and 3-connected nodes, which lead to an unusual (3,9)-connected net with Schläfli symbol of (4²³?·?6¹³)(4³). The solid 1 exhibits high thermal stability and shows strong blue fluorescence emission at 410?nm in the solid state at ambient temperature.