1D and 2D solid-state metallosupramolecular arrays of freebase 5,10,15,20-tetra(4-pyridyl)porphyrin, peripherally linked by zinc and manganese ions

Freebase 5,10,15,20-tetra(4-pyridyl)porphyrin (TPyP) is able to assemble into crystalline rigid 1D and 2D metallosupramolecular arrrays via exocyclic coordination with tetracoordinate and hexacoordinate metal ions, respectively. In this contribution we report on two coordination polymers of μ ⁴-bridging freebase TPyP with zinc and manganese halide moieties. The structure of [(ZnBr₂)₂TPyP] · 6 TCE (2) (TCE = 1,1,2,2-tetrachloroethane) consists of 1D polymeric chains. The topology of [(MnCl₂)TPyP] · 6 TCE (3) is the (4,4) square grid type. The crystal structure of the known compound [(HgI₂)₂TPyP] · 4 TCE (1) was redetermined by X-ray crystallography.     

卟啉二酸H4THSPP2+聚集状态的吸收光谱研究

强酸性条件下(pH＜0.2),H4THSPP2+的B带发生红移,表明有J类型聚集体(肩并肩排列)生成,溶剂极性的降低有利于H4THSPP2+形成J类型聚集体离子强度的增加使H4THSPP2+的B带发生蓝移,表明形成了H类型二聚体(面对面排列);研究同时表明,适当的离子强度有利于J类型聚集体的稳定,而过高的离子强度则会破坏J类型聚集体,并促使H类型二聚体的形成.     

Synthesis and molecular structures of heptafluoroisopropylated fullerenes: C60(i-C3F7)8, C60(i-C3F7)6, and C60(CF3)2(i-C3F7)2

One isomer of C₆₀(i-C₃F₇)₈, three isomers of C₆₀(i-C₃F₇)₆, and the first mixed perfluoroalkylated fullerene, C₆₀(CF₃)₂(i-C₃F₇)₂, have been isolated by HPLC from a mixture prepared by reaction of C₆₀ with heptafluoroisopropyl iodide in a glass ampoule at 260-290 °C. The molecular structures of the four new compounds have been determined by means of X-ray single crystal diffraction partially also by use of synchrotron radiation. Theoretical calculations at the DFT level of theory have been employed to rationalize the energetics of isomers and of C₆₀-R_f binding.     

Chains,helices, sheets and unusual 3D nets: Diverse structures of the flexible,ditopic ligand 1,2-bis(3-(4-pyridyl)pyrazolyl)ethane

The flexible ditopic ligand 1,2-bis(3-(4-pyridyl)pyrazol-1-yl)ethane (L^4Et) displays remarkable versatility in the complexes that it forms with transition metals with products ranging from 1D chains to interpenetrating 3D networks. The L^4Et ligand itself crystallises in the space group P2₁, adopting a helical twist, although it is found in a variety of other conformations in its complexes. Coordination polymers containing the L^4Et ligand vary from almost straight, parallel 1D chains of [Ag₂(L^4Et)₂(ClO₄)₂(DMF)]·DMF (1), through interdigitating helical complexes containing tetrahedral Zn(II), [Zn(NCS)₂(L^4Et)]·DMF·H₂O (2) to 2D sheets of [Cu(L^4Et)₂(H₂O)₂](PF₆)₂·xH₂O (3) and the three-fold interpenetrating 3D network of [Co(L^4Et)₂(NCS)₂] (4). The 3D network adopts an unusual 3D 4-connected dmp (6⁵.8) topology. Dimensionality can be limited by the use of chelating co-ligands, demonstrated by the formation of the dinuclear complex [{Cu(py-2,6-CO₂)(H₂O)}₂(L^4Et)] (5).     

Synthesis of 5,10,15,20-tetra[3-(o- andm-carboranyl)butyl]porphyrins containing the C−B σ-bond

5,10,15,20-Tetra[3-(o- andm-carboranyl)butyl]porphyrins containing carborane groups bonded to alkyl substituents of the porphyrin cycle by the C−B σ-bond were obtained by condensation of 4-(o- andm-carboran-9-yl)pentanals with pyrrole. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 347–349, February, 1998.     

Syntheses,Structures, and Theoretical Studies of New Mercury Iodobismuthates: (Et4N)4(Bi4Hg2I20) and (nBu4N)2(Bi2HgI10)

The first two mercury iodobismuthates, (Et₄N)₄(Bi₄Hg₂I₂₀) ( 1 ) and (nBu₄N)₂(Bi₂HgI₁₀) ( 2 ) have been synthesized by the reactions of binary BiI₃ and HgI₂ in a mixed solution of ethanol/acetone with the existence of different ammonia cations. The novel hexanuclear (Bi₄Hg₂I₂₀)^4– anion in 1 can be viewed as a dimer of the trinuclear (Bi₂HgI₁₀)^2– anion in 2 . The DFT calculations reveal that the band gaps of both compounds are determined only by the anionic moieties and therefore are similar, which agrees with the experimental measurements.     

Crystal Structure and Disorder Phenomena of the Adduct of Neutral C60 and the Ionic Gold Complex (Ptol3)2AuNO3

The adduct C₆₀·(Ptol₃)₂AuNO₃ has been crystallized from toluene solutions of C₆₀ and (Ptol₃)₂AuNO₃ as violet, trigonal plate‐shaped crystals. The compound was studied by single‐crystal x‐ray diffraction ( , a = 1278.17(3), c = 2282.92(6) pm). The gold complex is dissociated into [(Ptol₃)₂Au]⁺ cations, which encapsulate the neutral C₆₀ molecules, and nitrate anions. The intermolecular interactions between the fullerene molecules and the gold complex cations and the resulting disorder is investigated. The crystal structure of C₆₀·(Ptol₃)₂AuNO₃ is providing an instructive example, demonstrating that symmetry‐matching is not always sufficient for avoiding disorder.     

Crystal Structure of the Mixed‐Valent Basic Mercury Nitrate HgI2(NO3)2·HgII(OH)(NO3)·HgII(NO3)2·4HgIIO [= Hg8O4(OH)(NO3)5]

Light‐yellow single crystals of the mixed‐valent mercury‐rich basic nitrate Hg₈O₄(OH)(NO₃)₅ were obtained as a by‐product at 85 °C from a melt consisting of stoichiometric amounts of (Hg^I₂)(NO₃)₂·2H₂O and Hg^II(OH)(NO₃). The title compound, represented by the more detailed formula Hg^I₂(NO₃)₂·Hg^II(OH)(NO₃)·Hg^II(NO₃)₂·4Hg^IIO, exhibits a new structure type (monoclinic, C2/c, Z = 4, a = 6.7708(7), b = 11.6692(11), c = 24.492(2) Å, β = 96.851(2)°, 2920 structure factors, 178 parameters, R1[F² > 2σ(F²)] = 0.0316) and is made up of almost linear [O‐Hg^II‐O] and [O‐Hg^I‐Hg^I‐O] building blocks with typical Hg^II‐O distances around 2.06Å and a Hg^I‐O distance of 2.13Å. The Hg₂²⁺ dumbbell exhibits a characteristic Hg‐Hg distance of 2.5079(7) Å. The different types of mercury‐oxygen units form a complex three‐dimensional network exhibiting large cavities which are occupied by the nitrate groups. The NO₃^? anions show only weak interactions between the nitrate oxygen atoms and the mercury atoms which are at distances > 2.6Å from one another. One of the three crystallographically independent nitrate groups is disordered.     

Crystal Structure and Thermal Behaviour of the Mixed‐Valent Basic Mercury Nitrate HgI2(OH)(NO3)·HgIIO

Single crystals of the hitherto unknown compound Hg₂(OH)(NO₃)·HgO were obtained unintentionally during hydrothermal phase formation experiments in the system Ag—Hg— As—O. Hg₂(OH)(NO₃)·HgO (orthorhombic, Pbca, Z = 8, a = 6.4352(8), b = 11.3609(14), c = 15.958(2) Å, 1693 structure factors, 83 parameters, R1[F² > 2σ(F²)] = 0.0431) adopts a new structure type and is composed of two types of mercury‐oxygen zig‐zag‐chains running perpendicular to each other and of intermediate nitrate groups. One type of chains runs parallel [010] and consists of (Hg—Hg—OH) units with a typical Hg—Hg distance of 2.5143(10) Å for the mercury dumbbell, whereas the other type of chains runs parallel [100] and is made up of (O—Hg—O) units with short Hg—O distances of about 2.02Å. Both types of chains are concatenated by a common O atom with a slightly longer Hg—O distance of 2.25Å. The three‐dimensional assembly is completed by nitrate groups whose O atoms show Hg—O distances > 2.80Å. Weak hydrogen bonding between the OH group and one oxygen atom belonging to the nitrate group stabilizes this arrangement. Hg₂(OH)(NO₃)·HgO decomposes above 200 °C to HgO.     

Use of cerium oxide (CeO(2)) as a packing material for the chromatographic separation of C(60) and C(70) fullerenes

Cerium oxide (CeO₂) was tested as a packing material in liquid chromatography for the separation of C₆₀ and C₇₀ fullerenes. The separation of C₆₀ and C₇₀ fullerenes could be achieved within 20 min by using pure n-hexane as the mobile phase. Furthermore, some higher fullerenes could also be separated in less than 40 min. The peak area was reproducible to a large extent. The separation of fullerenes by liquid chromatography on CeO₂ is shown to be an effective method for their isolation in large amounts. The column efficiency of the CeO₂ column was compared with commercial silica gel and ODS columns. The main advantage of the CeO₂ column is its ability to separate large amounts of fullerenes (C₆₀ and C₇₀) in toluene.     

Spectroscopic,thermal and structural studies of a new mercury(II) one-dimensional coordination polymer, [Hg(3-bpo)2(SCN)2], 3-bpo = 2,5- bis (3-pyridyl)-1,3,4-oxadiazole

A new mercury(II)-organic polymeric complex generated from 2,5-bis(3-pyridyl)-1,3,4-oxadiazole (3-bpo) as an angular dipyridyl derivative ligand, [Hg(3-bpo)₂(SCN)₂], was prepared from reactions of ligand 3-bpo with mercury(II) thiocyanate. The compound was characterized by elemental analysis, IR-, ¹H NMR-, ¹³C NMR-spectroscopy and structurally determined by X-ray single crystal diffraction. The thermal stability of [Hg(3-bpo)₂(SCN)₂] was studied by thermal gravimetric (TG) and differential thermal analyses (DTA).     

Synthesis and Structure of [Hg{OP(O)CF3(OH)}2(PMe3)3], a Distorted Trigonal Bipyramidal Complex Connected by Hydrogen Bridges to Polymeric Chains

The hydrolysis of [Hg{P(CF₃)₂}₂(PMe₃)₂] yields colourless crystals of [Hg{OP(O)CF₃(OH)}₂(PMe₃)₃]. The proposed multistep reaction proceeds via primary hydrolysis of the starting material giving HgO and HP(CF₃)₂. The latter is directly oxidized by HgO to (CF₃)₂P(O)OH. The bis(trifluoromethyl)phosphinic acid hydrolyses to CF₃P(O)(OH)₂ which reacts with [Hg{P(CF₃)₂}₂(PMe₃)₂] in the presence of PMe₃ to the title compound. The crystal structure was determined by X‐ray single‐crystal analysis (triclinic; P1¯; a = 860.7(1), b = 1007.6(2), c = 1625.0(3) pm; α = 96.09(2), β = 101.09(2), γ = 107.79(2)°; Z = 2) and exhibits distorted trigonal bipyramidal mercury complexes which are connected to polymeric chains. The acidic units, {OP(O)CF₃(OH)}^—, are connected via intermolecular hydrogen bridges, forming two individual centrosymmetric eight membered rings with asymmetric hydrogen bridges with O—O distances of 249.4(8) and 250.8(8) pm.     

Preparation and Crystal Structures of the Hydrous Mercury Tellurates,HgII(H4TeVIO6) and HgI2(H4TeVIO6)(H6TeVIO6)·2H2O

Single crystals of Hg^II(H₄Te^VIO₆) (colourless to light‐yellow, rectangular plates) and Hg^I₂(H₄Te^VIO₆)(H₆Te^VIO₆)·2H₂O (colourless, irregular) were grown from concentrated solutions of orthotelluric acid, H₆TeO₆, and respective solutions of Hg(NO₃)₂ and Hg₂(NO₃)₂. The crystal structures were solved and refined from single crystal diffractometer data sets (Hg^II(H₄Te^VIO₆): space group Pna2₁, Z = 4, a =10.5491(17), b = 6.0706(9), c = 8.0654(13)Å, 1430 structure factors, 87 parameters, R[F² > 2σ(F²)] = 0.0180; Hg^I₂(H₄Te^VIO₆)(H₆Te^VIO₆)·2H₂O: space group P1¯, Z = 1, a = 5.7522(6), b = 6.8941(10), c = 8.5785(10)Å, α = 90.394(8), β = 103.532(11), γ = 93.289(8)°, 2875 structure factors, 108 parameters, R[F² > 2σ(F²)] = 0.0184). The structure of Hg^II(H₄Te^VIO₆) is composed of ribbons parallel to the b axis which are built of [H₄TeO₆]^2— anions and Hg²⁺ cations held together by two short Hg—O bonds with a mean distance of 2.037Å. Interpolyhedral hydrogen bonding between neighbouring [H₄TeO₆]^2— groups, as well as longer Hg—O bonds between Hg atoms of one ribbon to O atoms of adjacent ribbons lead, to an additional stabilization of the framework structure. Hg^I₂(H₄Te^VIO₆)(H₆Te^VIO₆)·2H₂O is characterized by a distorted hexagonal array made up of [H₄TeO₆]^2— and [H₆TeO₆] octahedra which spread parallel to the bc plane. Interpolyhedral hydrogen bonding between both building units stabilizes this arrangement. Adjacent planes are stacked along the a axis and are connected by Hg₂²⁺ dumbbells (d(Hg—Hg) = 2.5043(4)Å) situated in‐between the planes. Additional stabilization of the three‐dimensional network is provided by extensive hydrogen bonding between interstitial water molecules and O and OH‐groups of the [H₄TeO₆]^2— and [H₆TeO₆] octahedra. Upon heating Hg^I₂(H₄Te^VIO₆)(H₆Te^VIO₆)·2H₂O decomposes into TeO₂ under formation of the intermediate phases Hg^II₃Te^VIO₆ and the mixed‐valent Hg^IITe^IV/VI₂O₆.     

Structural characterization of a copper(II) complex containing oxidative cyclization of N-2-(4-picolyl)-N′-(4-methoxyphenyl)thiourea,new ligands of 4-picolylthiourea derivatives and the precursor molecular structure of oxidative cyclization of N-(2-pyridyl)-N′-(4-methoxyphenyl)thiourea

Three new compounds of aryl thiourea derivatives, namely N-2-(4-picolyl)-N′-(4-methoxyphenyl)thiourea (L1), N-2-(6-picolyl)-N′-(4-methoxyphenyl)thiourea (L2) and N-2-(4-picolyl)-N′-(4-nitrophenyl)thiourea (L3), and the new copper(II) complex [Cu(4PicTz4OMePh)(OAC)(EtOH)] (C1), as a result of oxidative cyclization of the ligand (L1), were synthesized. In addition, pure precursor (P1), as the product of the oxidative cyclization of N-(2-pyridyl)-N′-(4-methoxyphenyl)thiourea (L4), was isolated and characterized. Ligands (L1) and (L2) were characterized by ¹H and ¹³C NMR and single crystal X-ray analysis. ¹H NMR spectroscopy showed strong hydrogen bonding interactions between N′H-functionalities and the pyridine nitrogen atoms as well as weak intermolecular hydrogen bonding between the thione sulfur and the NH hydrogen. Structural studies of complex (C1) showed that the copper ion is five-coordinated with a square-pyramidal environment. The oxidative cyclization of ligand (L1) results in an anionic bidentate ligand in complex (C1). Both ligand (L1) and precursor (P1) crystallize as centrosymmetric dimers.     

The Molybdenum(V) Chelates Formed by the Reaction of Molydbdenum Hexacarbonyl or Molybdenum Pentachloride with Salicyl(2-pyridyl)aldazine

Abstract

Reaction of molybdenum hexacarbonyl with salicyl(2-pyridyl)aldazine leads to the formation of the dinuclear compound tetra(salicyl(2-pyridyl)aldazineato)-μ-oxodioxodimolybdenum(V). Reaction of the ligand with molybdenum pentachloride gives tris(salicyl(2-pyridyl)-aldazineato)oxomolybdenum(V) which reacts with thionyl chloride to form dicholortris(salicyl(2-pyridyl)aldazineato)molybdenum(V). The dicholoride undergoes a hydrogen chloride elimination reaction with aniline to give tris(salicyl(2-pyridyl)aldazineato)-bis(anilineato)molybdenum(V). Spin Hamiltonian parameters and e.s.r spectral linewidths have been determined from the e.s.r. spectra due to the molybdenum(V)chelates. Computer simulations of the S-band e.s.r. spectrum due to the dichlorotris(salicyl(2-pyridyl)aldazineato)molybdenum(V) points to a cis configuration of the chloride anion about the molybdenum(V) centre with one chloride anion in the of the predominantly 4dxy ground molybdenum(V) centre and the other chloride anion out of that plane.     

Assembly of 1-D and decanuclear cage compounds from copper halide,cyclohexenephosphonic acid,and 3-(2-pyridyl)pyrazole

The reactions of cyclohexenephosphonic acid (C₆H₉PO₃H₂) and 3-(2-pyridyl)pyrazole (2-pyPzH) with copper(II) chloride and copper(II) bromide affords a 1-D compound [Cu(2-pyPz)Cl] (1) and a decanuclear [Cu₁₀(OH)₄(C₆H₉PO₃)₆(2-pyPz)₄] (2) cage complex. In 1, adjacent copper ions are bridged by two 2-pyPz ligands into dimers, which are further linked by Cl^? into a ladder-like chain. Compound 2 has a decanuclear cage structure, the overall cage can be viewed as composed of two Cu₄(OH)₂(2-pyPz)₂ wings that are bridged by a central Cu₂P₂O₆ rim. Variable-temperature magnetic susceptibility studies indicate that both compounds show antiferromagnetic interactions between copper centers.