Single Crystal X-ray Molecular Structures Research Articles

Synthesis of New Cobalt(III) Meso-Porphyrin Complex, Photochemical, X-ray Diffraction, and Electrical Properties for Photovoltaic Cells.

The present work describes the preparation and characterization of a new cobalt(III) porphyrin coordination compound named (chlorido)(nicotinoylchloride)[meso-tetra(para-chlorophenyl)porphyrinato]cobalt(III) dichloromethane monosolvate with the formula [CoIII(TClPP)Cl(NTC)]·CH2Cl2 (4). The single-crystal X-ray molecular structure of 4 shows very important ruffling and waving distortions of the porphyrin macrocycle. The Soret and Q absorption bands of 4 are very red-shifted as a consequence of the very distorted porphyrin core. This coordination compound was also studied by fluorescence and cyclic voltammetry. The efficiency of our four porphyrinic compounds-the H2TClPP (1) free-base porphyrin, the [CoII(TClPP)] (2) and [CoIII(TClPP)Cl] (3) starting materials, and the new Co(III) metalloporphyrin [CoIII(TClPP)Cl(NTC)]·CH2Cl2 (4)-as catalysts in the photochemical degradation was tested on malachite green (MG) dye. The current voltage of complexes 3 and 4 was also studied. Electrical parameters, including the saturation current density (Js) and barrier height (ϕb), were measured.

Construction and Functionalization of Highly Strained N -Doped Zigzag Hydrocarbon Belts

Construction and Functionalization of Highly Strained <i>N</i> -Doped Zigzag Hydrocarbon Belts

A Convenient Approach to Luminescent Cyclometalated Platinum(II) Complexes with Organometallic π‐Bonded Benzenedithiolate

A family of neutral cyclometalated platinum(II) complexes [(C^N)Pt(η‐S^S)] with π‐bonded benzenedithiolate {(η‐S^S) = Cp*Ru(C6H4S2)} and various cyclometalated ligands, {(C^N) = 2‐phenylpyridine (ppy), (2); 2,4‐difluorophenylpyridine (F2ppy) (3), benzo[h]quinoline (bzq) (4); dibenzo[f,h]quinoline (dbzq) (5)} were prepared and fully characterized. For comparison purposes the related bipyridine platinum(II) complex [(bpy)Pt(η‐S^S)][OTf] (6) was also prepared. The electrochemistry behavior of these complexes was investigated and shows the enhanced stability of these compounds toward oxidation due to the presence of Cp*Ru moiety which is now π‐bonded to the benzenedithiolato group. Moreover, several complexes were identified by single‐crystal X‐ray molecular structures. To the best of our knowledge, these are the first structures to be reported for cyclometalated platinum complexes with a π‐bonded benzenedithiolate (bdt) ligand. All of the complexes are luminescent in fluid solution at room temperature and in glassy solution at 77 K; their emission properties can be tuned through ligand variation.

Synthesis, Crystal Structure, Electrochemical and Catalytic Properties of Hybrid Polyoxomolybdate Clusters-Based Terbium Complex

The inorganic–organic compound based on polyoxomolybdate [Tb(C2H6SO)8][PMo12 O40]·2C2H6SO·½H2O (I) has been isolated and structurally characterized by single-crystal X-ray molecular structure, IR spectra, thermogravimetric analysis and cyclic voltammetry measurements. The catalytic activities of (I) were also tested. The title compound crystallizes in monoclinic crystal system with C2/c space group. In the crystal, the polyoxidometalate anions are arranged in chains parallel to the [010] direction. The complex cations are located between these layers and linked to the neighbouring anions via weak C–H⋯O hydrogen bonding interactions leading to the formation of three dimensional network structure. Their catalytic activity toward organic dye is quite sizeable since the target removal is about 68% in the presence of the system POM-Tb/H2O2 after 120 min.

X-ray Molecular Structure of ({[(1E)-3-(1&lt;i&gt;H&lt;/i&gt;-Imidazol-1-yl)-1- phenylpropylidene]amino} oxy)(3,4,5-trimethoxyphenyl)- methanone: A Potential Anti-&lt;i&gt;Candida&lt;/i&gt; Agent

Purpose: To elucidate the solid-state conformation as well as the imine double bond configuration of a potential anti-Candida agent ({[(1E)-3-(1H-imidazol-1-yl)-1-phenylpropylidene]amino}oxy)(3,4,5trimethoxyphenyl)methanone. Methods: Acetophenone was used as a starting material to prepare the target oximino ester in a fourstep reaction sequence. Nuclear magnetic resonance ( 1 H-NMR and 13 C-NMR) and mass spectrometry were used to confirm the chemical structure of the synthesized compounds. Thereafter, x-ray crystallography was performed on single crystals of the target compound. The solid-state conformation of the target molecule and the (E)-configuration of its imine double bond were determined via the investigation of its single crystal x-ray molecular structure. Results: The titled compound crystallized in the triclinic space group P-1 with a = 11.0719 (7) A, b = 14.6602 (9) A, c = 14.8530 (9) A, α = 67.205 (4)°, β = 80.388 (5)o, γ = 70.100 (5)°, V = 2088.2 (2) A 3 , and Z = 4. Individual molecules were packed in the crystal by three weak non-classical intermolecular hydrogen interactions, including C9A—H9AA•••O3A, C9B—H9BA•••O3B, C18B—H18C•••O2A and C20B—H20B•••O4B. Conclusion: The results of the single crystal x-ray molecular structure of the titled anti-Candida agent unequivocally confirmed its (E)-configuration.

Synthesis and structure of iron(III) complexes of amine-bis(phenolate) ligands

The synthesis and structures of four new iron(III) amine-bis(phenolate) complexes are reported. Reaction of anhydrous FeCl3 with the diprotonated tridentate ligand isopropyl-N,N-bis(2-methylene-4-t-butyl-6-methylphenol) (H2L1) and NEt3 produces the trigonal bipyramidal iron(III) complex [NEt3H]+ [FeCl2L1]– (1). The reaction of FeBr3 with the sodium or lithium salts, Na2L1 and Li2L2, results in the formation of FeBr2L1H (2) and FeBr2L2H (3), tetrahedral iron(III) complexes possessing two bromide ligands and quaternized ammonium fragments. A trigonal bipyramidal FeIII hydroxido-bridged dimer, [Fe(μ-OH)L2]2 (4), was also isolated during the synthesis of 3. Single-crystal X-ray molecular structures have been determined for complexes 1–4 and H2L2.

Magnetic, electrochemical and spectroscopic properties of iron(iii) amine–bis(phenolate) halide complexes

Eight new iron(III) amine-bis(phenolate) complexes are reported. The reaction of anhydrous FeX(3) salts (where X = Cl or Br) with the diprotonated tripodal tetradentate ligands 2-tetrahydrofurfurylamino-N,N-bis(2-methylene-4,6-di-tert-butylphenol), H(2)L1, 2-tetrahydrofurfurylamino-N,N-bis(2-methylene-4-methyl-6-tert-butylphenol), H(2)L2, and 2-methoxyethylamino-N,N-bis(2-methylene-4,6-di-tert-butylphenol), H(2)L3, 2-methoxyethylamino-N,N-bis(2-methylene-4-methyl-6-tert-butylphenol), H(2)L4 produces the trigonal bipyramidal iron(III) complexes, L1FeCl (1a), L1FeBr (1b), L2FeCl (2a), L2FeBr (2b), L3FeCl (3a), L3FeBr (3b), L4FeCl (4a), and L4FeBr (4b). All complexes have been characterized using electronic absorption spectroscopy, cyclic voltammetry and room temperature magnetic measurements. Variable temperature magnetic data were acquired for complexes 2b, 3a and 4b. Variable temperature Mössbauer spectra were obtained for 2b, 3a and 4b. Single crystal X-ray molecular structures have been determined for proligand H(2)L4 and complexes 1b, 2b, and 4b.

Synthesis of Novel Indeno[1,2-c]isoquinoline Derivatives

Indeno[1,2-c]isochromene was prepared using the readily obtainable starting materials via the condensation of dimethyl homophthalate with 3,4-dimethoxybenzaldehyde in the presence of sodium methoxide in absolute methanol followed by saponification and cyclization with concentrated sulfuric acid at 0°C. The proclivity of cyclized product for undergoing nucleophilic addition has been tested by reaction with nitrogen nucleophiles. Structural assignments are based on spectroscopic data (infrared, 1H NMR, 13C NMR, and mass spectra) and confirmed by the single-crystal x-ray molecular structure (2 and 3).

Synthesis, structure and properties of the mixed-ligand tungsten(II) complex [WBr2(CO)3(tmpymt)] (tmpymt = 1,4,6-trimethylpyrimidine-2-thione)

In the mononuclear seven-coordinated complex [WBr 2 (CO) 3 (tmpymt)]·C 3 H 6 O the W II atom adopts a distorted capped trigonal prism (CTP) geometry. The single-crystal X-ray molecular structure was compared to the optimized molecular structure (RHF/LanL2DZ) and the results are convergent to CTP geometry. The reaction of [{WBr(CO) 4 } 2 (μ-Br) 2 ] 2 1 with 1,4,6-trimethylpyrimidine-2-thione (tmpymt) affords the air-sensitive complex [WBr 2 (CO) 3 (tmpymt)] 2 . The X-ray structure of 2 ·C 3 H 6 O reveals that the geometry surrounding the tungsten(II) atom is best described as a distorted capped trigonal prism with a bromine atom Br(1) in the unique capping position. The other bromine atom Br(2), the (N,S)-chelate and one carbonyl C(41) occupy the capped quadrilateral face. The complex has been additionally characterized by IR and NMR spectroscopy. The optimized molecular structure (RHF/LanL2DZ) supports the experimental data.

Synthesis and structure of iron(iii) diamine-bis(phenolate) complexes

The structures and properties of six new iron(iii) diamine-bis(phenolate) complexes are reported. Reaction of anhydrous FeX(3) salts (where X = Cl or Br) with the diprotonated tripodal tetradentate ligands 2-pyridylamino-N,N-bis(2-methylene-4-methyl-6-tert-butylphenol), H(2)[L(1)], and N,N-dimethyl-N',N'-bis(2-methylene-4-methyl-6-tert-butylphenol)ethylenediamine, H(2)[L(2)], produces the trigonal bipyramidal iron(iii) complexes, [L(1)]FeCl , [L(1)]FeBr , [L(2)]FeCl and [L(2)]FeBr . Reaction of FeX(3) with the related linear tetradentate ligand N,N'-bis(4,6-tert-butyl-2-methylphenol)-N,N'-bismethyl-1,2-diaminoethane, H(2)[L(3)], generates square pyramidal iron(iii) complexes, [L(3)]FeCl and [L(3)]FeBr . Complexes have been characterized using electronic absorption spectroscopy and magnetometry. Single crystal X-ray molecular structures have been determined for complexes 1, 3, 5 and 6.

Regioselective Synthesis of 4′‐Amino‐1′H‐spiro[cyclohexane‐1,2′‐(pyrimido [1,2‐a]benzimidazole)]‐3′‐carbonitrile in Aqueous Medium.

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Regioselective Synthesis of 4′-amino-1′H-spiro[cyclohexane-1,2′-(pyrimido [1,2-a]benzimidazole)]-3′-carbonitrile in Aqueous Medium

A simple, mild and environment-friendly procedure for synthesis of 4′-amino-1′H-spiro[cyclohexane-1,2′-(pyrimido[1,2-a]benzimidazole)]-3′-carbonitrile is developed using microwave irradiation in water. The product is obtained in short time, in excellent yield, and in a good state of purity. The reaction pathway and the influence of reaction conditions on regiochemistry are also investigated. The regioselectivity in this process is confirmed chemically and by single-crystal X-ray molecular structure determination.

Mild and ecofriendly tandem synthesis of 1,2,4-triazolo[4,3-a]pyrimidines in aqueous medium

A rapid, efficient, clean and environmentally benign exclusive synthesis of 1,2,4-triazolo(4,3- a)pyrimidines from the reaction of amino triazole, carbonyl compounds and alkene-nitrile derivatives has been developed in an aqueous medium in an excellent yields using microwaves or ultrasonic waves. The results are compared with conventional heating. Structural assignments are based on spectroscopic data (IR, 1 HNMR, 13 CNMR, mass spectra). Further the product structure is confirmed by the single-crystal X-ray molecular structure of 7'-amino-8'H-spiro (cyclohexane- 1,5'-(1,2,4) triazolo (4,3-a) pyrimidine)-6'-carbonitrile (4g).

Supramolecular Assemblies of Trinuclear Triangular Copper(II) Secondary Building Units through Hydrogen Bonds. Generation of Different Metal−Organic Frameworks, Valuable Catalysts for Peroxidative Oxidation of Alkanes

Formation of the trinuclear triangular copper derivative [Cu3(mu3-OH)(mu-pz)3(EtCOO)2(H2O)] x H2O, 1b (Hpz = pyrazole), has been simply achieved by addition of Hpz to a water solution of Cu(EtCOO)2 x H2O and leaving the resulting solution to crystallize at ca. 12 degrees C. When the reaction and crystallization were carried out at a slightly higher temperature (18-22 degrees C), the compound [Cu3(mu3-OH)(mu-pz)3(EtCOO)2(H2O)], 1c, formed. Single-crystal X-ray molecular structure determinations show that both compounds have analogous trinuclear triangular structures, but very different supramolecular assemblies, due mainly, but not only, to the crystallization molecule of H2O in 1b. In particular, contrarily to the previously reported, strictly related, [Cu3(mu3-OH)(mu-pz)3(EtCOO)2(EtOH)], 1a, the propionate ions in 1b and 1c do not bridge different triangular units, whereas they are involved in intra- and intermolecular H-bonds, generating complex supramolecular 2-D MOFs. Compounds 1a and 1c act as remarkably active and selective catalysts or catalyst precursors for liquid biphasic (MeCN/H2O) peroxidative oxidation of cyclohexane and cyclopentane to the corresponding alcohols and ketones.

2,5-Dichloro-1-(ROSO 2)benzene [R = C 6H 5, C 6F 5, and CH 2(CF 2) 4H]: Synthesis, molecular structure, and solubility in supercritical CO 2

Highly crystalline phenyl 2,5-dichlorobenzenesulfonate (PDBS, T melt = 86–87 °C) and pentafluorophenyl 2,5-dichlorobenzenesulfonate (FPDBS, T melt = 120–122 °C) were synthesized. Single-crystal X-ray molecular structure determinations show that both compounds have similar three-dimensional molecular structures; however, PDBS crystals are thin platelets and FPDBS crystals form hexagonal tube-like structures that are predominately hollow at one end. PDBS crystals exhibit offset π-stacking of the phenoxy-rings that form complete two-dimensional layers each two molecules thick. Hydrogen-bonding interactions are calculated at ∼3.2 Å between the C6-hydrogen and the sulfonyl-oxygen of a neighboring molecule. On the other hand, for FPDBS, π-stacking of the dichloro-substituted ring as well as dipole–dipole interactions of the fluorinated-phenoxy rings appears to be the predominate intermolecular interactions. Neither structure exhibits any kind of side-on interaction of the phenyl rings. PDBS and FPDBS exhibit melting point depressions of 26 and 40 °C, respectively, in the presence of supercritical CO 2. Although both sulfonates exhibit high solubility in CO 2, much lower pressures are needed to dissolve FPDBS compared to PDBS. For example, at 100 °C FPDBS dissolves at 4750 psia and PDBS dissolves at 11,000 psia. The solubility data reinforce the observation that fluorinating a compound can significantly lower the conditions needed to dissolve that compound in CO 2.

Synthesis, structure and characterization of new complexes [Fe 2(μ-OMe) 2(PAP)(X) 4] (PAP= 1,4-di(2 ′-pyridyl)aminophthalazine, X=Cl, OAc) and their oxidation catalysis

Two dinuclear iron(III) complexes with tetradentate N-donor ligand 1,4-di(2 ′-pyridyl)aminophthalazine (PAP), [Fe 2(μ-OMe) 2(PAP)Cl 4] ( 2) and [Fe 2(μ-OMe) 2(PAP)(OAc) 4] ( 3) were prepared and characterized. Single crystal X-ray molecular structure of [Fe 2(μ-OMe) 2(PAP)Cl 4] · 2MeOH have been elucidated. The six-coordinate iron atoms are in distorted octahedral environment bridged by the oxygen atoms of two methoxy groups and the PAP ligand. The Mössbauer spectra of both complexes show one quadrupole doublet and the isomer shift and quadrupole splitting values indicate the presence of octahedral high-spin Fe III ions. Complex 2 showed catalytic activity for alkane oxidation with hydrogen peroxide.

Synthesis and characterization of [(CO)4FeL-L] and [(CO)4FeL-LFe(CO)4] wherein L-L is N(CH2CH2)3N and also P(NMeNMe)3P in the latter complex: single crystal X-ray molecular structure of [Fe(CO)4DABCO

Herein we report the syntheses and characterization of the novel title mono- and dinuclear compounds from pentacarbonyliron. They were obtained in a stepwise manner by UV irradiation of [Fe(CO)5] with the appropriate ligand in THF and were characterized by ¹H, 13C, 13C{¹H} 31P and 31P{¹H} NMR spectroscopy, by IR spectroscopy and by elemental analysis. The single crystal X-ray molecular structure of [Fe(CO)4(DABCO)] is described. The 13C{¹H} NMR spectra of each of the title complexes reveal their fluxional behavior, which presumably occurs via Berry pseudorotation.

Synthesis and structures of dinuclear low-coordinate lithium and zirconium(iv) complexes derived from the diamido ligands 1,3-(CH2N̄C6H3R12)2C6H4(R1= Me or Pri)

Treatment of 1,3-bis(bromomethyl)benzene with two equivalents of the appropriate compound Li[N(H)C6H3R12-2,6] yielded the diamines 1,3-[CH2N(H)C6H3R12-2,6]2C6H41 [R1 = Me, abbreviated as H2(D)] or 2 [R = Pri, abbreviated as H2(D′)]. The crystalline complex [Li2(D′)]23 was obtained from 2 and 2 LiBun; the analogue from 1 and 2 LiBun was an incompletely characterised oil. The binuclear, crystalline zirconium(IV) amides [{Zr(NMe2)3}2(μ-D′)] 4, its D analogue 5 and [{Zr(NMe2)2}2(μ-D)2] 6 were prepared from [{Zr(NMe2)3(μ-NMe2)}2] and H2(D′) [or 2 H2(D′)], H2(D) and 2 H2(D), respectively. The single crystal X-ray molecular structures of complexes 3 and 4 have been elucidated. That of 3 comprises a sixteen-membered, twisted macrocyclic LiNC5NLiNC5N core with each of the two-coordinate lithium atoms part of the LiNLiN rhombus. The four-coordinate zirconium atoms in 4 are in an only slightly distorted tetrahedral environment, with the two Zr(NMe2)3 units arranged trans to one another across the central aromatic ring. None of 4–6, with MAO, showed catalytic activity for ethylene polymerisation under ambient conditions.

Synthesis of Higher-Nuclearity Clusters by Use of Small Cluster Units as Building Blocks: Synthesis and X-Ray Structure Analysis of [ClCCo3(CO)8]2(μ-dppe) and [ClCCo3(CO)7][ClCCo3(CO)8](μ-TRIPHOS) (dppe = 1,2-bis(diphenylphosphino)ethane; TRIPHOS = bis(2-diphenylphosphinoethyl)phenylphosphine)

Abstract Two ClCCo3(CO)9 units are, after treatment with Me3NO, linked at basal cobalt atoms by dppe spacer to yield [ClCCo3(CO)8]2(μ-dppe) and by TRIPHOS to yield [ClCCo3(CO)7][ClCCo3(CO)8](μ-TRIPHOS); they are characterized by single crystal X-ray molecular structure analysis and two Cl atoms in the TRIPHOS derivative are found to be located in close proximity.

Synthesis, characterization, and polymerization of new ferrocene-fluorene complexes. A novel high-molecular-weight conjugated polymer with pendant ferrocene groups

Abstract : Ferrocenecarboxaldehyde was successfully condensed with fluorene derivatives to afford a series of new complexes, (eta5-C5H5) Fe(eta5-C5H4CH=(9- fluorenyl)) where fluorenyl = 1A, 2-bromo: 2a, 2,7-dibromo; 3, 2-nitro. The ferrocene-fluorenyl derivatives la and 2a were converted to the monocarboxaldehyde, tributylstannyl, bis(carboxaldehyde), and bis(tributylstannyl) complexes (lb, lc, 2b, and 2c, respectively). Complexes lb and 2b were characterized by single-crystal x-ray molecular structures. The fluorenyl ring systems were tilted out of the eta5-C5H4 plane by 39 deg. Treatment of lc and 2c with I2 afforded the mono- and bis(iodo)fluorenyl complexes ld and 2d, respectively. The reactivity of complexes 2a-d was explored. The alkynylation (alkyne, L2PdCl2, CuI, PPh3) of 2a was an extremely poor reaction giving little or no cross-coupling. Complex 2b did not undergo the Knoevenagel polycondensation with bis(cyanoacetate) comonomers. Treatment of 2c with acid chlorides under Stille cross-coupling conditions afforded ketone product and iodobenzene showed no cross-coupling. Complex 2d did copolymerize very cleanly with 2,5(diethynyl)-1,4-(decoxy)benzene using palladium catalysis to afford a soluble, high-molecular weight conjugated polymer, 4. A model compound, 5, was prepared from cross-coupling ld with 2,5-(diethynyl)-1,4- (decoxy)benzene.