Synthesis and crystal structure of 15α,20α-di(4-hydroxylphenyl)calix[4]pyrroles and 10α,20β-di(4-hydroxylphenyl)calix[4]pyrroles

In the presence of methanesulfonic acid as catalyst, the condensation reactions of 5,5′-dialkyldipyrromethanes with p-hydroxyacetophenone in methanol resulted in a mixture of the unexpected polysubstituted 15α,20α-di(4-hydroxylphenyl)calix[4]pyrroles and the expected 10α,20β-di(4-hydroxylphenyl)calix[4]pyrroles in comparable lower yields. The crystal structures of the new calix[4]pyrroles and their oxyacetate derivatives were successfully determined by X-ray diffraction and the intermolecular interactions in the solid state is briefly discussed.     

Synthesis and properties of polyimides derived from bis-(Aminophenoxy) containing naphthalene, [Phenyl] propane and [Methyl] cyclohexane segment and 4, 4′-carbonyldiphthalic anhydride

ABSTRACT

Three wholly, semi aromatic and aliphatic-aromatic polyimides containing bis(phenoxy) naphthalene, bis[(phenoxy) phenyl] propane and bis(phenoxy-methyl) cyclohexane segments by the two-step procedure from 2, 7-bis(4-aminophenoxy) naphthalene (BAPON), 2, 2-bis[4-(4-aminophenoxy)phenyl]propane (BAPOP), 1, 4-bis (4-aminophenoxy methyl) cyclohexane (BAPMC) as a diamine and 4,4′-carbonyldiphthalic anhydride (CDPA) were prepared. The first step of this procedure including ring-opening polyaddition in a polar solvent to give poly(amic-acid)s, second step containing cyclodehydration reaction to form polyimides. Synthesized monomer and polyimides were characterized by FT-IR, ¹H NMR spectroscopy and elemental analyses (CHN) that obtained results gave the most powerful evidence. The polyimide synthesized from BAPON was characterized as semi-crystalline, whereas the other polyimides showed amorphous patterns by the x-ray diffraction studies. The inherent viscosity was ranging between 0.87–1.01 dL/g. Tensile strength, initial moduli, and elongation at break of the polyimide films ranged from 88–117 MPa, 1.98–2.32 GPa, and 5–8%, respectively. Thermogravimetric analysis in nitrogen atmosphere shows that these polymers having good stability, so 10% weight will be lost in the range of 500–630°C. The point of polyimide with BAPMC segment, is “adding of good thermal stability and processability” lower moisture absorption and dielectric constant (0.75% and 2.90).     

Spectroelectrochemical studies of [Mo(dtc)_4][Eu(dtc)_4] and [Mo(dtc)_4][Er(dtc)_4]

Redox and spectroscopic properties of the eight-coordination complexes of molybdenum and the rare-earth elements Eu or Er with N,N-diethyldithiocarbamate (dtc) were characterised by cyclic voltamrnetry and UV-visible absorption spectra.The complex cation [Mo(dtc)4]+ is more stable than the complex anions [Eu(dtc)4]-and [Er(dtc)4]-in redox processes,and possesses good redox reversibility.The electron transfer number,formal standard electrode potential in the redox process for the complex cation and its diffusion coefficients were obtained by in aitu spectroelectro-chemistry.     

Complex salts of [ReII(NO)Br4(pyz)]−: synthesis,crystal structures,and DFT studies

Two nitrosyl Re(II) complexes formulated as [Ni(bipy)₃][Re(NO)Br₄(pyz)]₂ and [Cu(bipy)₂Br][ReNOBr₄(pyz)] (pyz = pyrazine, bipy = 2,2′-bipyridine) were synthesized and characterized by single-crystal X-ray diffraction. The pyrazine in [Re(NO)Br₄(pyz)]^? was not able to act as bridge toward a second metal ion, and the two salts were obtained. Computational studies at the density functional level of theory show that the charge on the nitrogen, which could be available for bridging, is dramatically reduced to less than half, decreasing its capability to bind a second metal ion.     

Syntheses, structure, and a Mössbauer and magnetic study of Ba(4)Fe(2)I(5)S(4)

The compound Ba4Fe2I5S4 has been prepared at 1223-1123 K by the "U-assisted" reaction of FeS, BaS, S, and U with BaI2 as a flux. A more rational synthesis was also found; however, the presence of U appears to be essential for the formation of single crystals suitable for X-ray diffraction studies. Ba4Fe2I5S4 crystallizes in a new structure type with two formula units in space group I4/m of the tetragonal system. The structure consists of a Ba-I network penetrated by (1)infinity[Fe2S4] chains. Each Fe atom, which is located on a site with 4 symmetry, is tetrahedrally coordinated to four S atoms. The FeS4 tetrahedra edge-share to form linear (1)infinity[Fe2S4] chains in the [001] direction. The Fe-Fe interatomic distance in these chains is 2.5630(4) A, only about 3% longer than the shortest Fe-Fe distance in -Fe metal. Charge balance dictates that the average formal oxidation state of Fe in these chains is +2.5. The M?ssbauer spectra obtained at 85 and 270 K comprise a single quadrupole doublet that has hyperfine parameters consistent with an average Fe oxidation state of +2.5. The M?ssbauer spectrum obtained at 4.2 K consists of a single magnetic sextet with a small hyperfine field of -15.5 T. This spectrum is also consistent with rapid electron delocalization and an average Fe oxidation state of +2.5. The molar magnetic susceptibility of Ba4Fe2I5S4, obtained between 3.4 and 300 K, qualitatively indicates the presence of weak pseudo-one-dimensional ferromagnetic exchange within a linear chain above 100 K and weak three-dimensional ordering between the chains at lower temperatures.     

Synthesis,mesomorphic and dielectric properties of 4-(cyanomethoxy)phenyl 4-alkoxybenzoates, 4-(cyanomethoxy)-4′-alkoxyazo- and -azoxybenzenes

Preparation methods were developed for homologs of 4-(cyanomethoxy)phenyl 4-alkoxybenzoates (C₇, C₈, C₉), 4-(cyanomethoxy)-4′-alkoxyazo (C₂, C₃, C₆), -azoxybenzenes (C₃, C₆) whose composition and structure were proved by elemental analysis and ¹H NMR spectra. 4-(Cyanomethoxy) group destabilizes the mesophase, consequently, only four among the compounds obtained exhibit the thermotropic nematic mesomorphism.     

Synthesis,Crystal and Molecular Structures of [Co(MH)2(Thio)2][BF4] · H2O and [Co(DH)2(NH3)2][BF4]

Crystal structures of [Co(MH)₂(Thio)₂][BF₄] · H₂O (I) and [Co(DH)₂(NH₃)₂][BF₄] (II), where MH^– is H₃C–C(NOH)–C(NO^–)–H and DH^– is H₃C–C(NOH)–C(NO^–)–CH₃, were determined by X-ray diffraction. The crystals are monoclinic, space group C2/c, unit cell parameters (for I and II, respectively): a = 22.018(2) Å, b = 7.943(1) Å, c = 11.681(1) Å, = 92.68(1)° and a = 21.436(2) Å, b = 6.400(2) Å, c = 12.389(2) Å, = 113.13(1)°. In both cases, the Co(III) coordination polyhedron is a centrosymmetrical trans-octahedron, N₄S₂ for I and N₆ for II. In the crystals of I and II, the complex cations and the outer-sphere [BF₄]^– anions (and the crystal water molecules in I) form elaborate hydrogen bonding system.     

Synthesis and Crystal Structure of Bis[O, O '-bis(4-tert-butylphenyl)dithiophosphate] nic kel(Ⅱ)

A new O,O'-bis(4-tert-butylphenyl)dithiophosphate complex Ni[SSP(OC6H4But- p)2]2 (1) was synthesized and characterized by elemental analysis, IR, 1H NMR, thermogravimetric analysis (TGA) and single-crystal X-ray diffraction. The crystal belongs to the monoclinic system, space group P21/c with a = 12.8440(3), b = 6.18686(12), c=26.3018(5) , β=92.6135(18)°, V = 2087.87(7) 3, Z = 2, Dc = 1.345 g/cm3, μ = 0.780 mm-1, the final R = 0.0316 and wR = 0.0748 (Ⅰ >2σ(Ⅰ)). A total of 4269 unique reflections were collected, of which 3621 with Ⅰ > 2σ(Ⅰ) were observed. The NiII atom lies on an inversion center and is chelated by two (p-ButC6H4O)2PSS-ligands in a [NiS4] square-planar geometry with Ni-S bonds of 2.2408(5) and 2.2444(5) , respectively. A stepwise 1D chain structure is constructed via intermolecular S…S and C-H…S interactions. According to our knowledge this is the first case that intermolecular S…S interaction is observed in mononuclear transition metal complex of O,O'-dialkyldithiophosphates.     

Structure of thiocarbamide-containing cobalt(III) dioximates with [BeF4]2− and [BF4]− anions

The crystal structure of the complexes [Co(DH)₂(Tu)₂]₂[BeF₄]·C₂H₅OH (I) and [Co(DfH)₂(Tu)₂][BF₄] 0.5H₂ (II) (where DH^? is the dimethylglyoxime monoanion, DfH^? is the α-benzyldioxime monoanion, and Tu is thiourea) has been determined by X-ray diffraction analysis. The coordination polyhedron of the Co³⁺ atom is an N₄S₂ octahedron formed by four nitrogen atoms of the dioxime molecule and two sulfur atoms of the fragments of thiourea (Tu); the latter have parallel and perpendicular orientations relative to the dioxime residue. The deviation of the cobalt atom from the four-angle plane (formed by the nitrogen atoms of the dimethylglyoxime residues) does not exceed 0.019 Å. The Co-N and Co-S distances vary from 1.877(3) Å to 1.901(3) Å and from 2.280(1) Å to 2.307(1) Å, respectively. The statistically disordered cations [BeF₄]^2? and [BF₄]^? play an important role in crystal formation — they form a complex system of hydrogen bonds.     

Synthesis and Characterization of a Novel Copoly(aryl ether ketone) Containing 4, 4''''-Biphenyl-bis[4-phthalazin-1(2H)-one] Moiety

Poly(aryl ether ketone)s are a category of high performance engineering thermoplastics characterized by high glass transition temperature and excellent thermooxidative stability. And they have important applications in electronic, electric, aircraft and aerospace industries1~3. Considerable efforts have been made towards the improvement of solubility or processability of poly(aryl ether ketone)s4,5. In our work, a novel bis(phthalazinone) monomer 1 4, 4-biphenyl-bis[4-phthalazin-1(2H)-one] …     

Synthesis, Electrochemistry and Crystal Structure of the [Ni36Pt4(CO)45]6− and [Ni37Pt4(CO)46]6− Hexaanions

The [Ni₃₆Pt₄(CO)₄₅]^6- and [Ni₃₇Pt₄(CO)₄₆]^6- clusters have been obtained in mixture upon reaction in acetonitrile of [Ni₆(CO)₁₂]^2- salts with K₂PtCl₄ in a 2.5:1 molar ratio. The two hexaanions were indistinguishable by spectroscopic techniques. Crystallization of their trimethylbenzylammonium salts led to crystals of composition 0.5[NMe₃CH₂Ph]₆[Ni₃₆Pt₄(CO)₄₅]-0.5[NMe₃CH₂Ph]₆[Ni₃₇Pt₄(CO)₄₆]·C₃H₈O, hexagonal,space group P6₃ (No. 173), a=17.853(9), c=27.127(13) Å, Z=2; final R=0.057. The metal core of the [Ni₃₆Pt₄(CO)₄₅]^6- anion consists of a Pt₄ tetrahedron fully encapsulated in a shell of 36 Ni atoms belonging to a very distorted and incomplete ₅ tetrahedron. The [Ni₃₇Pt₄(CO)₄₆]^6- hexaanion derives from the former by capping the unique triangular face of the metal polyhedron with an additional Ni(CO) fragment. The [Ni₃₆Pt₄(CO)₄₅]^6--[Ni₃₇Pt₄(CO)₄₆]^6- mixture is rapidly degraded to the known [Ni₉Pt₃(CO)₂₁]^4- cluster by exposure to carbon monoxide. Its reaction with protic acids initially affords the corresponding [H_6-nNi₃₆Pt₄(CO)₄₅]^n--[H_6-nNi₃₇Pt₄(CO)₄₆]^n- (n=5, 4) derivatives, and eventually leads to rearrangement to the known [H_6-n Ni₃₈Pt₆(CO)₄₈]^n- species. Both [Ni₃₆Pt₄(CO)₄₅]^6--[Ni₃₇Pt₄(CO)₄₆]^6- and [HNi₃₆Pt₄(CO)₄₅]^5--[HNi₃₇Pt₄(CO)₄₆]^5- mixtures have been chemically and electrochemically reduced to their corresponding [Ni₃₆Pt₄(CO)₄₅]^n--[Ni₃₇Pt₄(CO)₄₆]^n- (n=7–9) and [HNi₃₆Pt₄(CO)₄₅]^n--[HNi₃₇Pt₄(CO)₄₆]^n- (n=6–8) mixtures.     

Synthesis, crystal structure, spectroscopic, magnetic, theoretical, and microbiological studies of a nickel(II) complex of L-tyrosine and imidazole, [Ni(Im)2(L-tyr)2]·4H2O

The [Ni(Im)(2)(L-tyr)(2)]·4H(2)O (1) complex was obtained in crystalline form as a product of interaction of L-tyrosine sodium salt, imidazole, and NiSO(4). The X-ray structure was determined, and the spectral (IR, FIR, NIR-vis-UV, HF EPR) and magnetic properties were studied. The Ni(2+) ion is hexacoordinated by the N and O atoms from two L-tyrosine molecules and by two N atoms of imidazole, resulting in a slightly distorted octahedral [NiN(2)N(2)'O(2)] geometry with a tetragonality parameter T = 0.995. The bands observed in the electronic spectra were ascribed to the six spin-allowed electronic transitions (3)B(1g) → (3)E(g) and (3)B(2g), (3)B(1g) → (3)A(2g) and (3)E(g), and (3)B(1g) → (3)A(2g) and (3)E(g). The spin Hamiltonian parameters g, D, and E, which were determined from high-field HF EPR spectra, excellently reproduced the magnetic properties of the complex. Calculation of the zero-field splitting in the S = 1 state of nickel(II) using DFT and UHF was attempted. The biological activity of the complexes has been tested for antifungal and antibacterial effects against Aspergillus flavus, Fusarium solani, Penicillium verrucosu, Bacillus subtilis, Serratia marcescens, Pseudomonas fluorescens, and Escherichia coli.     

Synthesis and Structure of Tungsten Carbonyl Compound with 2-Mercapto Pyrimidine [Et_4N] [W (CO)_4(SC_4H_3,N_2) ]

1INTR0DUCTI0NLowva1encemolybdenum/tungstencomp1exeswiththiolatoligandsareusefulforthestudiesonsyntheticandstructuralchemistry.Inrecentyearswehavesynthe-sizedandcharacterizedaseriesofdinuclearMo-SRc0mpoundscontainingaplanarMoSzMocorewithamon0dentatethiolatoligand"-"anda"butterfly"M0S2Mocorewithabidentatethi0latoligand"=."H0wdoesmultidentateliganddo"hasnaturallyattracted0urinterest-2-mercaptoPyrimidine(PymS)wasusedasamultidentateligandtocarry0utsynthesisexperiment.unexpectedly,whichgavea…     

Synthesis and Crystal Structure of 4,4'-(4-(1-Naphthyl)-4-phenyl-1,3-butadienylidene)-bis[N,N-diethylbenzenamine]

1 INTRODUCTION Organic photo-conductors (OPCs), due to their great advantages over inorganic ones, have been widely used in xerography and holography and aroused considerable interest in the past several de- cades. Recently, almost all OPCs are of a layered structure with a thin charge generation layer (CGL) and a charge transport layer (CTL). Current resear- ches are directed to both improving the chara- cteristics of existing OPCs and developing new ma- terials for future applicati…     

Heterocyclizations of Di- and Tricarbonyl Indole Derivatives. Synthesis of β-Carbolines, 3H-[1,2,5]Triazepino-[5,4-a]indol-4(5H)-one,and 5,10-Dihydro[1,2]diazepino-[4,5-b]indol-4(3H)-one

Russian Journal of Organic Chemistry - A synthetic approach to β-carbolines has been proposed on the basis of heterocyclization of ethyl 2-(2-benzoyl-1H-indol-3-yl)acetate with...     

Synthesis,crystal structure and Raman spectra of [dabcoH2]CuICl3, [dabcoH2]3Cl4CuIICl4(DMSO) and Cu3Cl3(dabco)(DMSO) (dabco = 1,4-diazabicyclo [2.2.2] octane)

Dissolving elemental copper in a CCl₄–DMSO mixture in the presence of dabco (dabco = 1,4-diazabicyclo [2.2.2] octane) resulted in the formation of a compound with the composition [dabcoH₂][CuCl₃] featuring a univalent copper salt. This compound, composed of discrete dabcoH₂²⁺ cations and CuCl₃^2? anions, represents the first example of a copper(I) chloride derivative containing a doubly protonated [dabcoH₂]²⁺ unit, and a very rare example of the oxidative dissolving of copper in a CCl₄–DMSO mixture to give a Cu(I) compound. The addition of some drops of water to the initial reaction mixture led to the formation of the [dabcoH₂]₃Cl₄CuCl₄(DMSO). Three [dabcoH₂]²⁺ units and four Cl^? anions, bound via N–H…Cl hydrogen bonds, form a horseshoe-like cationic fragment. The divalent copper ion possesses a rather unusual pseudo-tetrahedral surrounding. The comproportionation reaction of CuCl₂·2H₂O and copper powder in the presence of dabco in DMSO results in the formation of the Cu₃Cl₃(dabco)(DMSO) complex. Copper and chlorine ions form unprecedented Cu₆Cl₆ cores, interconnected by neutral dabco linkers into infinite 2-D layers. All the compounds were characterized using the single-crystal X-ray diffraction technique and Raman spectroscopy.     

Synthesis, molecular structures, and properties of heterometallic cobalt tetramethylcyclobutadiene complexes (C4Me4)Co(CO)2TePh, (C4Me4)Co(CO)2TePh[W(CO)5], and Me4C4Co(μ3-S)2Cr2Cp2(μ-SC4H9)

The reaction of Cb*Co(CO)₂I (1) (Cb* is tetramethylcyclobutadiene) with sodium phenyltelluride afforded the mononuclesar complex Cb*Co(CO)₂TePh (2). The reaction of the latter with W(CO)₅(THF) produced the Cb*Co(CO)₂TePh[W(CO)₅] compound (4). The reaction of 1 with the Cp₂Cr₂(SCMe₃)₂S complex gave the heterometallic cluster Cb*Co(μ₃-S)₂Cr₂Cp2 (μ-SCMe₃) (5). Complexes 2, 4, and 5 are diamagnetic. Their structures were determined by X-ray diffraction. Complex 2 contains the Co-Te bond (2.585(1) Å); complex 4, the Co-Te (2.558(8) Å) and W-Te (2.8467(6) Å) bonds. Complex 5 has the stable triangular sulfide-and tert-butylmercaptide-bridged core Cr₂Co (Cr-Cr and Cr-Co bond lengths are 2.626(2) and 2.673(2) Å, respectively) with Cp ligands at the chromium atoms and a Cb* ligand at the cobalt atom. Complex 5 was characterized by cyclic voltammetry. The thermolysis of complex 4 was studied.     

Synthesis,structure, and electrochemical properties of [M(N-MeIm)6]2+ (M = Ni,Co, Cu) associated with [HgCl4]2−

Reaction of Hg(NO₃)₂ with 4 equivalent KI in water afford K₂[HgI₄]. By using K₂[HgI₄] as the precursor, three new heterobimetallic compounds [Ni(N-MeIm)₆][HgI₄] (I), [Co(N-MeIm)₆][HgI₄] (II), and [Cu(N-MeIm)₆][HgI₄] (III) have been characterized by elemental analysis, IR spectra, and the singlecrystal X-ray crystallorgraphy analysis. Three complexes are isomorphous and crystallized in monoclinic symmetry space group P2₁/c. The coordination around each center metal(II) atom is octahedral with six nitrogen atoms of N-MeIm ligand. Each structure contains one tetrahedral [HgI₄]^2? as an anion to balance the charge of the molecular. Thermogravimetry analysis indicates these complexes have the similar departure process and cyclic voltammogram exhibits a significant pair of redox peaks.