Three Mn(II) complexes with 1,3-bis(4-pyridyl)propane and their supramolecular nets

Three complexes, [Mn(bpp)₄(H₂O)₂](ClO₄)₂?·?1.5H₂O (1), [Mn(bpp)₃Br₂]?·?2H₂O (2), and [Mn(bpp)₂(H₂O)₂](ClO₄)?·?I?·?H₂O?·?bpp (3) (bpp?=?1,3-bis(4-pyridyl)propane), were synthesized and structurally characterized by single-crystal X-ray diffraction. Complex 1 is mononuclear where M(II) is coordinated to a monodentate TT-bpp, three monodentate TG-bpp, and two water molecules. Complex 2 possesses a single-stranded helical chain formed from MnN₄Br₂ octahedra by a single TT-bpp, with pendant monodentate TG-bpp ligands. Complex 3 consists of a ribbon-type double-stranded chain formed from MnN₄O₂ octahedra by double TG-bpp ligands. 2-D supramolecular architectures of 1–3 are formed by hydrogen bonds. The fluorescence of the three complexes comes from the π*–π transition of the ligand.     

Exchange reactions of 1,3-bis(nitroarylthio)propanes with propane-1,3-dithiols

Base-catalyzed reactions of propane-1,3-dithiols with 2-chloronitrobenzene, 3,4-dichloronitrobenzene, and 2-chloro-3-nitropyridine afforded 1,3-bis(nitroarylthio)propanes, whose thiolate-thiolate exchange with propane-1,3-dithiols gave dihydrobenzodithiepines. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 163–166, January, 2006.     

Molecular structure and vibrational spectra of 1,3-bis(4-pyridyl)propane by quantum chemical calculations

The experimental and theoretical study on the structures and vibrations of 1,3-bis(4-pyridyl)propane are presented. The FT-IR and Raman spectra of molecule have been measured. The optimized geometric bond lengths have been obtained by DFT show the best agreements with experimental values. The harmonic vibrational frequencies were calculated and scaled values have been compared with experimental FT-IR and FT-Raman spectra. Majority of the computed wavenumbers were found to be in good agreement with experimental observations. A complete assignment of the fundamentals was proposed based on the total energy distribution (TED) calculation.     

Theoretical and experimental study on metal(II) halide complexes of 1,3-bis(4-pyridyl)propane

We report the results of detailed experimental and theoretical studies on the molecular structure and vibrational spectra of metal(II) halide complexes of 1,3-bis(4-pyridyl)propane [M(N₂C₁₃H₁₄)X₂, where M represents Zn or Hg, and X represents Cl, Br, or I]. The FT–infrared spectra (FT-IR) and FT-Raman spectra of the metal complexes of the 1,3-bis(4-pyridyl)propane molecule in the powder form were recorded between the 400–4000 and 5–3500 cm^?1 regions, respectively. The molecular geometry and vibrational frequencies of the metal complexes of 1,3-bis(4-pyridyl)propane in the ground state were calculated using density functional theory (B3LYP functional) with LANL2DZ and SDD as basis sets. The total energy distributions (TED) among the symmetry coordinates of the normal modes were computed for the low-energy structure of the molecules. Complete vibrational assignments based on the calculated TED values are given.     

2D-layered structure of coordination polymer,zinc trifluoroacetate-1,3-bis(4-pyridyl)propane

Compound [Zn(CF₃CO₂)₂(Bpp)₂], where Bpp is 1,3-bis(4-pyridyl)propane, was synthesized and its structure and luminescent properties were determined. Crystals are monoclinic, space group C2/c, a = 21.261(1) Å, b = 17.642(1) Å, c = 18.632(1) Å, β = 115.85(1)°, V = 6289.3(6) ų, ρ_calcd = 1.453 g/cm³, Z = 8. The structure comprises 2D neutral layers of conjugated multiunit rings composed of four Zn²⁺ ions united by four bridging Bpp ligands. Each of two crystallographically nonequivalent Zn atoms is coordinated at the octahedra apices to four nitrogen atoms of two Bpp ligands and two O(CF₃CO₂) atoms. Trifluoroacetate anions are coordinated to Zn²⁺ ions in monodentate manner. The compound exhibits photoluminescence in solid state.     

Transition metal complexes with squarate anion and the pyridyl-donor ligand 1,3-bis(4-pyridyl)propane (BPP): Synthesis,crystal structure and spectroscopic investigation

Synthesis, crystal structure and the vibrational spectra of coordination polymers with 1,3-bis(4-pyridyl)propane (BPP) and squarate ion ligands and transition metal ions (M = Mn²⁺, Co²⁺, Ni²⁺, Cu²⁺ and Zn²⁺) are described. All compounds are isostructural, and the BPP is not coordinated to metal site since it is in cationic form due to protonation of N atoms from pyridyl rings. The metal is coordinated to two squarate ions and two water molecules in an octahedral distorted geometry. The two water molecules are involved in medium hydrogen bonds with squarate ligands and the average of O?O distance is 2.679(3) Å. Squarate ions adopt the 1,3-bis(monodentate) coordination mode bridging two metal centers giving rise to a 2D arrangement with (4,4) topology. The four-member ring is slightly distorted and the M–M distances are respectively 8.024 and 8.111 Å. The cationic form of BPP molecules are located inside of four-member ring cavity, presenting two different orientations, in which one molecule is inverted comparing to another. Vibrational spectra of all compounds are very similar, in agreement to crystal data. In all infrared spectra of the compounds a medium band at 1640 cm⁻¹ is observed, assigned to the in plane deformation mode of NH bond, indicative of the formation of cationic BPP. In the Raman spectra of the investigated compounds is observed a weak band around 1800 cm⁻¹, assigned to the stretching mode of free CO bond, whereas the medium band observed around 1600 cm⁻¹ is tentatively assigned to coordinated CO stretching mode. At last, a very important achievement of this investigation refers to the coordination geometries of all the investigated compounds, which are governed only by the ligands, independently of the different electronic properties of the metal ions.     

Pseudorotaxane-type n-hydrocarbon container. Metallacyclodimer of ionic palladium(II) complexes containing 1,3-bis(4-pyridyl)tetramethyldisiloxane

An unusual "pseudorotaxaned n-alkane within a metalla-cyclodimer" system, C(n)H(2n+2)@[(Me(4)en)Pd(L)](2)(CF(3)SO(3))(4) (n = 5, 6, 7; Me(4)en = N,N,N',N'-tetramethylethylenediamine; L = 1,3-bis(4-pyridyl)tetramethyldisiloxane), was constructed. This system is the first pseudorotaxane-type petroleum container achieved via the appropriate size effect.     

Synthesis, structure, spectroscopic properties, and photochemistry of homo- and heteropolynuclear copper(I) complexes bridged by the 2,5-bis(2-pyridyl)pyrazine ligand

Cu(I)-Cu(I) and Cu(I)-Ru(II) dinuclear complexes bridged by the 2,5-bppz (2,5-bis(2-pyridyl)pyrazine) ligand have been prepared and characterized including the X-ray crystallographic study of the dinuclear [{CuI(PPh3)2}2(mu-2,5-bppz)](PF6)2)2CH3Cl complex: a = 13.974(2), b = 13.993(2), c = 13.537(2) A; alpha = 101.98(1), beta = 103.22(1), gamma = 113.90(1) degrees ; triclinic, P, Z = 1. The trinuclear [{(bpy)2RuII(mu-2,5-bppz)}2CuI](PF6)5 complex was also prepared, and the structure of the complex in solution was studied by spectrometric titration. The dinuclear Cu(I) complex and [(bpy)2RuII(mu-2,5-bppz)CuI(PPh3)2](PF6)5 show photoluminescence in the solid state, which should arise from MLCT states. Photochemical oxidation of the trinuclear RuII2CuI complex occurs in the presence of oxygen to give a RuII2CuII complex. The MLCT states and the redox reaction in the excited state are discussed.     

Spectroscopic, thermal and structural studies of cocrystal of 2,2′-diamino-4,4′-bis(1,3-thiazole) with 4,4′-bipyridine, 1,2-bis(4-pyridyl)ethylene and 1,3-bis(4-pyridyl)propane

Three new cocrystals based upon 2,2′-diamino-4,4′-bis(1,3-thiazole) (DABTZ) with 4,4′-bipyridine (4,4′-bipy), 1,2-bis(4-pyridyl)ethylene (bpe) and 1,3-bis(4-pyridyl)propane (bpp): [(DABTZ) (4,4′-bipy)], [(DABTZ) (bpe)] and [(DABTZ) (bpp)] have been synthesized and characterized by elemental analysis, IR-, ¹H NMR-, ¹³C NMR spectroscopy and studied by thermal and X-ray crystallography. Self-assembly of these compounds in the solid state is likely caused by both hydrogen bonding, and π-π stacking.     

Phenyl-functionalized diiron propanediselenolato complexes containing the chelated or bridged 1,3-bis(diphenylphosphine)propane ligand

Abstract

Reaction of precursor Fe₂[(μ-SeCH₂)₂CHC₆H₅](CO)₆ (A) with 1,3-bis(diphenylphosphine)propane (dppp) in refluxing xylene yielded one diphosphine-containing complex Fe₂[(μ-SeCH₂)₂CHC₆H₅](CO)₄(κ²-dppp) (1) with the diphosphine of dppp displacing the apical and one basal carbonyl ligands of a single iron center, while treatment of precursor A with one-half equivalent of dppp in MeCN in the presence of Me₃NO·2H₂O gave another diphosphine-containing complex {Fe₂[(μ-SeCH₂)₂CHC₆H₅](CO)₅}₂(μ,κ¹,κ¹-dppp) (2) with the diphosphine of the dppp bridging two diiron diselenolato clusters upon replacing one of basal carbonyls, respectively. The structures of both complexes were fully characterized by spectroscopic methods and X-ray crystallography. The electrochemical behaviors of both complexes were investigated by cyclic voltammetry (CV) and the electrochemical reduction of protons from acetic acid to give dihydrogen catalyzed by complex Fe₂[(μ-SeCH₂)₂CHC₆H₅](CO)₄(κ²-dppp) was observed.     

Direct observation of light induced spin transitions in new 3,5-bis(2-pyridyl)pyrazolato bridged thiocyanato diiron(II) complexes by monitoring variable temperature laser Raman spectra

The light induced excited spin state trapping LIESST and the reverse LIESST-like phenomena are observed below and above the spin transition temperature, respectively, for new dinuclear diiron(II) complexes and familiar Fe(II) complexes with thiocyanate ligands by monitoring the Raman spectra where only excitation light of various wavelengths for the spectroscopy was used without extra excitation light sources.     

The transition metal carbonyl complexes of 1,3-bis(di-R-stibino)propanes (R = Me or Ph)

The synthesis and characterisation of complexes of two distibinopropanes R₂Sb(CH₂)₃SbR₂ (R = Me or Ph) with a variety of metal carbonyls is described. These include cis-[M(CO)₄{R₂Sb(CH₂)₃SbR₂}] (M = Cr, Mo or W), [{Fe(CO)₄}₂{μ-R₂Sb(CH₂)₃SbR₂}], [{Ni(CO)₃}₂{μ-R₂Sb(CH₂)₃SbR₂}], [Co₂(CO)₆{Ph₂Sb(CH₂)₃SbPh₂}], [Co₂(CO)₄{Me₂Sb(CH₂)₃SbMe₂}₃][Co(CO)₄]₂ and [Mn₂(CO)₈{Ph₂Sb(CH₂)₃SbPh₂}]. The complexes have been characterised by analysis, mass spectrometry, IR and multinuclear NMR spectroscopy as appropriate. Comparison of the spectroscopic data on these complexes with those of other stibine complexes and with complexes of Group 16 ligands has been used to establish the relative electronic properties of the distibines.     

1,3-二联苯基-2，4-二吡啶基环丁烷的结构与光化学性质

通过反-1-(4-联苯基)-2-(4-吡啶基)乙烯(EI)在稀硫酸中的光二聚反应合成了r-1,c-2,t-3,t-4-1,3-双(4-联苯基)-2,4-二(4-吡啶基)环丁烷(II).用X射线衍射法测定了其结构.晶体II为单斜晶系,空间群为P2     

Heterosynthons in molecular complexes of azopyridine and 1,2-bis(4-pyridyl)ethylene with dicarboxylic acids

A series of co-crystals of azaaromatic molecule with the present of dicarboxylic acid, [SA·BPE], [FA·AZP], [AA·BPE], [AA·AZP], [SEA·AZP] and [OA·AZP] (BPE=1,2-bis(4-pyridyl)ethylene, AZP=azopyridine, SA=succinic acid, FA=fumaric acid, AA=adipic acid, SEA=sebacic acid, OA=oxalic acid), have been synthesized for the regularity investigation of their supramolecular alignments driven by hydrogen bonding. It is significant for the design and synthesis of supramolecular co-crystals with multiple components. For linear molecules with recognition sites on both ends, the stacking regularity of the molecules in the co-crystals is proposed that the interlaced arrangement (motif III) is preferred when the size of the azaaromatic molecule is comparable with that of dicarboxylic acid and the inclined arrangement (motif II) is adopted when the length of azaaromatic molecule is much different from those of dicarboxylic acids.