Cyclic butadiyne-linked porphyrin(2.1.2.1) oligomers

2020 ◽  
Vol 24 (01n03) ◽  
pp. 489-497 ◽  
Author(s):  
Daiki Kuzuhara ◽  
Wataru Furukawa ◽  
Naoki Aratani ◽  
Hiroko Yamada
Keyword(s):  
Cyclic Voltammetry ◽  
Nmr Spectroscopy ◽  
Fluorescence Spectra ◽  
Theoretical Calculations ◽  
Cyclic Structure ◽  
Absorption And Fluorescence Spectra ◽  
H Nmr ◽  
Reduction Potentials ◽  
Cyclic Trimer ◽  
Tof Ms

Cyclic butadiyne-linked porphyrin(2.1.2.1) oligomers are synthesized from 5,16-diethynylporphyrin(2.1.2.1) by Glaser–Hay coupling. Porphyrin(2.1.2.1) forms a bent structure which gives advantages for making cyclic structure without templating molecules. We isolated cyclic trimer and tetramer and characterized them by MALDI-TOF-MS and [Formula: see text]H NMR spectroscopy, theoretical calculations, UV-vis absorption and fluorescence spectra and cyclic voltammetry. The cyclic structure mainly affects the reduction potentials because of expansion of [Formula: see text]-conjugations through butadiyne-linkages to stabilize their LUMOs.

Synthesis, Characterization and Photophysical Properties of Rhenium(I) Complexes Containing 4,5-Diazafluorene Ligan

2011 ◽  
Vol 239-242 ◽  
pp. 2612-2615
Author(s):  
Jie Xiu Wang ◽  
Feng Zhao
Keyword(s):  
Charge Transfer ◽  
Fluorescence Spectra ◽  
Photophysical Properties ◽  
Absorption And Fluorescence Spectra ◽  
Rhenium Complexes ◽  
H Nmr ◽  
Ligand Charge Transfer

Two related tricarbonyl rhenium complexes with the formula of [Re(CO)3(L)Cl], where L=4,5-diazafluoren-9-one (Dafo-Re) and 9-(phenylamino)-4,5-diazafluoren (PADF-Re) were successfully synthesized with the aim to explore the effect of the geometry of Dafo on Rhenium(I) coordination, and characterized by1H NMR. Photophysical behaviors are investigated by UV–vis absorption and Fluorescence spectra. The two complexes Dafo-Re and PADF-Re show metal-to-ligand charge transfer absorptions at ca.391nm, ca.394 nm and emissions at ca.492nm, ca.470nm, respectively.

Synthesis, Electronic States, and Electroluminescent Properties of Aluminum Complex Based on Mixed Ligands with 8-Hydroxyquinolinate and Acetylacetone

2011 ◽  
Vol 306-307 ◽  
pp. 358-361
Author(s):  
Liu Qing Chen ◽  
Chun Yan Sun ◽  
Xu Guang Liu ◽  
Bing She Xu
Keyword(s):  
Fluorescence Spectra ◽  
Orbital Energy ◽  
Computational Studies ◽  
Absorption And Fluorescence Spectra ◽  
Aluminum Complex ◽  
Analysis Techniques ◽  
H Nmr ◽  
Mixed Ligands ◽  
Organic Electroluminescent ◽  
Electron Transport Properties

We report the synthesis, photophysical investigation, computational studies and electroluminescent(EL) properties of an organic electroluminescent material-Bis(8-hydroxyQuino line) acetylacetone aluminum (Alq2A). It is characterized by 1H NMR, IR and elemental analysis techniques. The absorption and fluorescence spectra of various Alq2A systems including solution in ethanol, powder and thin film on quartz (thickness of 50nm) have also been systematically evaluated. Analysis of the electronic structure of Alq2A calculated by quantum chemical calculations reveals a localization of orbital and the distribution of orbital energy. The results from EL experiments indicate that Alq2A has good electron transport properties as compared with tris(8-hydroxyquinolinato) aluminum (Alq3). Thus, Alq2A is considered to be a superior emitter and electron transporting material for display application compared with Alq3.

Synthesis of perialkynylated tetrapyrazinoporphyrazines and its Optical Properties

2009 ◽  
Vol 2009 (5) ◽  
pp. 312-316 ◽  
Author(s):  
Chun Keun Jang ◽  
Jae Yun Jaung
Keyword(s):  
Optical Properties ◽  
Nmr Spectroscopy ◽  
Laser Desorption ◽  
Diels Alder ◽  
Visible Spectroscopy ◽  
H Nmr ◽  
Uv Visible ◽  
Tof Ms ◽  
Matrix Assisted Laser ◽  
Matrix Assisted Laser Desorption

Some phthalocyanines soluble in organic solvents have been developed by peripheral introduction of substituent groups. We report a new method for preparation of the polyphenyl-substituted dicyanopyrazines based on the [2 + 4] Diels-Alder cycloaddition of the tetraphenylcyclopentadienone to an ethynyl compound. The synthesised tetrapyrazinoporphyrazinato metal complexes were characterised by UV-visible spectroscopy, MALDI-TOF-Ms (matrix-assisted laser desorption ionisation time-of-flight mass) spectroscopy, and 1H NMR spectroscopy.

Electrochemical Study of Tricarbonyl(η6-cyclooctatetraene)metal(0) Complexes of the Group 6 Elements

1998 ◽  
Vol 53 (8) ◽  
pp. 875-880
Author(s):  
Giirkan Atinç Yilmaz ◽  
Ahmet M. Önal ◽  
Saim Özkar
Keyword(s):  
Cyclic Voltammetry ◽  
Nmr Spectroscopy ◽  
Supporting Electrolyte ◽  
Energy Levels ◽  
Dichloromethane Solution ◽  
Reduction Potentials ◽  
Ir And Nmr Spectroscopy ◽  
Group 6 ◽  
Constant Potential ◽  
Uv Visible

Abstract Tricarbonyl(η6-cyclooctatetraene)metal(0) complexes of the group 6 elements were prepared by using the procedures described in the literature with some minor modifications and identi­fied by IR and NMR spectroscopy. Their electrochemical behavior was studied by using cyclic voltammetry in dichloromethane solution containing 0.1 M tetrabutylammonium tetrafiuorob-orate as supporting electrolyte. Their oxidation and reduction potentials were measured and discussed in terms of the frontier energy levels in connection with the UV-Visible electronic ab­ sorption spectral data. In order to elucidate the mechanism of electrooxidation of the complexes, constant potential electrolysis was performed for one representative example, tricarbonyl(η6-cyclooctatetraene)chromium(O). The IR monitoring of the reaction showed that it is gradually converted to hexacarbonylchromium(O) upon electrolysis at constant potential.

Novel mono- and heterobimetallic chromium−nickel s-indacene complexes: synthesis, characterization, and DFT studies

2014 ◽  
Vol 92 (7) ◽  
pp. 677-683 ◽  
Author(s):  
Cesar Morales-Verdejo ◽  
Eduardo Schott ◽  
Ximena Zarate ◽  
Juan Manuel Manriquez
Keyword(s):  
Cyclic Voltammetry ◽  
Elemental Analysis ◽  
Molecular System ◽  
Theoretical Calculations ◽  
Dft Studies ◽  
Nickel Compound ◽  
H Nmr ◽  
Bridging Ligand ◽  
Ft Ir ◽  
C Nmr

The preparation of a novel heterobimetallic chromium−nickel compound (3), including 2,6-diethyl-4,8-dimethyl-5-hydroindacenide (IcH′) as bridging ligand was successfully achieved and it was characterized by means of 1H NMR, 13C NMR, and FT-IR spectroscopies and elemental analysis. Cyclic voltammetry studies were performed for complex 3 as well as for its respective mononuclear species. Theoretical calculations of this compound were carried out to gain further understanding of this novel molecular system.

A pentaammineruthenium(III) dimer with the novel bridging ligand 4,4′-dicyanamidobiphenyl dianion

1996 ◽  
Vol 74 (11) ◽  
pp. 2201-2208 ◽  
Author(s):  
Christopher A. White ◽  
Corinne Bensimon ◽  
Robert J. Crutchley ◽  
Manuel A.S. Aquino ◽  
J.E. Greedan
Keyword(s):  
Cyclic Voltammetry ◽  
Nmr Spectroscopy ◽  
Mixed Valence ◽  
The Novel ◽  
Temperature Dependent ◽  
Monoclinic Crystal ◽  
H Nmr ◽  
Weakly Coupled ◽  
Anti Conformation ◽  
Mixed Valence Complex

The novel ligand 4,4′-dicyanamidobiphenyl dianion (bp2−) has been synthesized and characterized by 13C NMR spectroscopy, cyclic voltammetry, and crystallography. The crystal structure of [Ph4As]2[bp]•H2O showed that bp2− is approximately planar with a dihedral angle of 8.2° between phenyl ring planes and the cyanamide groups in an anti conformation. The water of crystallization is asymmetrically hydrogen bonded between cyanamide groups of adjacent bp2− ions. The crystal data for C62H48N4As2 + H2O are monoclinic crystal system and space group P21/c with a = 12.998(5) Å, b = 13.465(4) Å, c = 28.703(13) Å, β = 98.94(3)°, V = 4963(3) Å3 and Z = 4. The structure was refined by using 4555 reflections with I > 2.5σ(I) to an R factor of 0.058. The complex, [{(NH3)5Ru)2(μ-bp)][X]4, where X = tosylate or PF6− ions, was also synthesized and characterized by 1H NMR spectroscopy, cyclic voltammetry, spectroelectrochemistry, and temperature-dependent magnetic susceptibility measurements. From cyclic voltammetry measurements, the comproportionation constants to form the mixed-valence complex [{(NH3)5Ru)2(μ-bp)]3+ were estimated to be 4.1, 16, and 22 in water, acetonitrile, and nitromethane, respectively. The trend and magnitude of Kc suggests solvent valence trapping of a weakly coupled Class II ion. The MMCT band of the mixed-valence complex had to be deconvoluted from the low-energy LMCT band and had the following properties in acetonitrile, νmax = 8400 cm−1, εmax = 3300 M−1 cm−1, and Δν1/2 = 3300 cm−1. The weak superexchange mediating properties of bp2− compared to 1,4-dicyanamidobenzene dianion were suggested to arise from the larger barrier to the formation of the radical anion bp−. Key words: cyanamido, mixed valence, superexchange, ruthenium.

scholarly journals Studies on the reactions of [AuCl4]− with different nucleophiles in aqueous solution

2014 ◽  
Vol 43 (23) ◽  
pp. 8620-8632 ◽  
Author(s):  
Mirjana D. Đurović ◽  
Ralph Puchta ◽  
Živadin D. Bugarčić ◽  
Rudi van Eldik
Keyword(s):  
Aqueous Solution ◽  
Cyclic Voltammetry ◽  
Kinetic Parameters ◽  
Theoretical Calculations ◽  
Stopped Flow ◽  
Flow Measurements ◽  
H Nmr ◽  
Rapid Scan

The type of reaction that occurs between [AuCl4]− and Br−, I−, NO2−, tu, py and DMSO, as well as their kinetic parameters, were determined using UV-vis, rapid-scan, stopped-flow measurements, cyclic voltammetry, 1H NMR and theoretical calculations.

A novel nitrogen-containing compound with D-π-A structure: theoretical and experimental study

2014 ◽  
Vol 92 (5) ◽  
pp. 411-416 ◽  
Author(s):  
Xiaoting Gong ◽  
Ziyan Zhou ◽  
Shuguang Zhang ◽  
Shuping Zhuo ◽  
Xiurong Huang ◽  
...  
Keyword(s):  
Density Functional ◽  
Fluorescence Spectra ◽  
Density Functional Theory Calculations ◽  
Absorption And Fluorescence Spectra ◽  
Functional Theory ◽  
H Nmr ◽  
Measured Absorption ◽  
Nmr Techniques ◽  
Good Agreement ◽  
C Nmr

2-(2-Hydroxy-styryl)-4,6-dimethyl-1,3,5-triazine (P1), a novel compound with D-π-A structure, possesses a variety of isomers. Density functional theory calculations were employed to explore the isomerization mechanisms of its various isomers at the 6-311+G** level. The calculated results show that the phenol configurations of compound P1 are more stable than the quinoid configurations, whether they exist as monomers, complexes, with methanol or dimers. The most stable structure of compound P1 was used to calculate the UV-vis and fluorescence spectra. To validate the calculated results, the title compound was synthesized and characterized by 1H NMR and 13C NMR techniques. The measured absorption and fluorescence spectra of P1 in methanol and N,N-dimethylformamide are in good agreement with the calculated ones.

Preparation of phthalocyanines fused with four tetrathiafulvalene units via the functional group transformation of tetrakis(o-xylylenedithio)phthalocyanines with toluene/aluminum chloride

2014 ◽  
Vol 18 (10n11) ◽  
pp. 884-890 ◽  
Author(s):  
Takeshi Kimura ◽  
Tadafumi Chiba ◽  
Shiduko Nakajo
Keyword(s):  
Cyclic Voltammetry ◽  
Optical Properties ◽  
Aluminum Chloride ◽  
Nickel Complex ◽  
Functional Group ◽  
H Nmr ◽  
Vis Spectroscopy ◽  
Thiolate Anions ◽  
Functional Group Transformation ◽  
Tof Ms

Tetrakis(o-xylylenedithio)phthalocyanine 5 and its nickel complex 5-Ni were treated with aluminum chloride in toluene to eliminate the peripheral o-xylylene groups. The thiolate anions generated from 5 and 5-Ni were reacted with carbonyldiimidazole to produce phthalocyanines 6 and 6-Ni with four 1,3-dithiole-2-one rings, respectively. Phthalocyanine 7a having four ethylenedithiotetrathiafulvalene units was prepared via the condensation of 6-Ni with ethylenedithio-1,3-dithiole-2-thiones. The reaction of 6-Ni with bis(methylthio)-1,3-dithiole-2-thiones gave phthalocyanine 7b with the corresponding TTF units. The structures of the products were determined by 1 H NMR and MALDI-TOF-MS. Their electrochemical and optical properties were examined by cyclic voltammetry and UV-vis spectroscopy.

Metall-π-Komplexe von Benzolderivaten, XLaSelen in der Peripherie des Bis(benzol)chroms: Darstellung, Strukturdynamik und Redoxverhalten eines neuen Hetera-[3]-chromocyclophans / Metal-π Complexes of Benzene Derivatives, XLaSelenium in the Periphery of Bis(benzene)chromium: Synthesis, Structural Dynamics, and Redox Behavior of a New Hetera-[3]-chromocyclophane

1992 ◽  
Vol 47 (8) ◽  
pp. 1157-1164 ◽  
Author(s):  
Christoph Elschenbroich ◽  
Heike Burdorf ◽  
Helmut Burdorf ◽  
Dagmar Mahrwald ◽  
Bernhard Metz
Keyword(s):  
Cyclic Voltammetry ◽  
Nmr Spectroscopy ◽  
Redox Potential ◽  
Structural Dynamics ◽  
Half Life ◽  
Redox Behavior ◽  
Benzene Derivatives ◽  
Subsequent Reaction ◽  
H Nmr ◽  
Electron Donation

Lithiation of bis(benzene)chromium and subsequent reaction with Ph2Se2 or Se and CH3I, respectively, afforded the complexes (PhSe-η6-C6H5)2Cr (6) and (MeSe-η6-C6H5)2Cr (8), the latter being convertible into interannularly bridged (MeSe-η6-C6H5)2Cr[M(CO)4] (9-11, M = Cr, Mo, W). According to 1H NMR spectroscopy, 9 undergoes both bridge inversion and reversal, the former displaying spectral coalescence at 283 K (ΔGc≠ = 55.9 kJ mol-1) whereas the latter is still rapid at 200 K. Substitution of H for –SeMe and addition of a Cr(CO)4 unit effect anodic shifts of the redox potential E1/2(+/0) of 95 mV/SeMe and 230 mV/Cr(CO)4. Despite electron donation from the bis(arene)metal backbone 8 is a fairly weak ligand, cleavage of the interannular bridge occuring with the half life τ1/2 = 41.4 min (9→8) and τ1/2 = 5.8 s (9+•→8+) as inferred from cyclic voltammetry in DME at 293 K.

Sign in / Sign up

Export Citation Format

Share Document