Charge-transfer Complexes Of Tetracyanoethylene Research Articles

Spectroscopic Characterization of Charge Transfer Complexes of TCNE with Aromatic Amines - The First Step of Tricyanovinylation Reaction

The first step of electrophilic aromatic substitution reactions generally involves the formation of charge transfer complexes. Tetracyanoethylene (TCNE) in the presence of aromatic amines forms π-type complexes that subsequently lead to tricyanovinylation reaction. Although this kind of reaction was investigated in the past, the spectroscopic characterization of the charge transfer complexes is still lacking, since in many cases the first step of the reaction is too fast to allow their characterization by conventional techniques. In this paper, it is shown the UV-Vis and resonance Raman characterization of the charge transfer complexes formed between TCNE and substituted anilines. The magnitude of the charge transfer could be linearly correlated with the electronic absorpion energies, as well as to the Raman shifts observed for the characteristic ν(C≡N) mode of TCNE. In addition, the results were correlated to ionization potentials of amines, and theoretical calculations by density functional theory/time-dependent density functional theory (DFT/TDDFT) methods were performed to support the experimental data.

Charge-Transfer Complexes of Tetracyanoethylene with Alkyl and Aryl Derivatives of the Halogens

Spectral characteristics (λCT, Δν1/2, and e) and association constants (in dichloromethane) of charge-transfer (CT) complexes of tetracyanoethylene (T) with donors containing C−X linkages (X = F, Cl, Br, and I) are presented. The donor orbitals from which CT transitions originate are identified by correlation of λCT and Δν1/2 values of CT bands of the complexes with the ionization bands of the photoelectron spectra of the donor molecules. CT energies of the complexes are influenced by intramolecular conjugative and inductive effects between halogen atoms and alkyl and aryl groups. Haloalkanes form weak complexes with T through interaction of the px and py orbitals of the halogen with the π* LUMO of T. Monoiodoalkane−T complexes exhibit two spectral bands arising from the transfer of nonbonded electrons from the 5p orbitals of iodine which are split into 2E1/2 and 2E3/2 states through spin−orbit coupling. λ1 and λ2 values of monoiodoalkanes increase progressively with increasing bulk of the alkyl group. Ha...

Charge-Transfer Complexes of Tetracyanoethylene with Alkyl and Aryl Derivatives of Sulfur, Selenium, and Tellurium

Charge-Transfer Complexes of Tetracyanoethylene with Alkyl and Aryl Derivatives of Sulfur, Selenium, and Tellurium

Formation Constants of Radical-Ion Pairs and Charge-Transfer Complexes of Tetracyanoethylene with Group 8 Metallocenes

Formation constants K i of radical-ion pairs and K c of charge-transfer (CT) complexes of tetracyanoethylene (T) with ferrocene and ruthenocene and some of their alkyl derivatives in dichloromethane (DCM) are presented. The spectra of some alkylmetallocene/T/DCM systems simultaneously exhibit CT bands for the feeble n-covalent complex and bands for the radical-ion pairs which follow electron transfer. K i and K c are calculated using a modified form of the Benesi-Hildebrand equation

Charge-Transfer Complexes of Tetracyanoethylene with Alkyl, Alkenyl, and Aryl Derivatives of Oxygen

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTCharge-Transfer Complexes of Tetracyanoethylene with Alkyl, Alkenyl, and Aryl Derivatives of OxygenJohn E. Frey, Theresa Aiello, Douglas N. Beaman, Scott D. Combs, Shi-lin Fu, and Jeffrey J. PuckettCite this: J. Org. Chem. 1994, 59, 7, 1817–1830Publication Date (Print):April 1, 1994Publication History Published online1 May 2002Published inissue 1 April 1994https://doi.org/10.1021/jo00086a037RIGHTS & PERMISSIONSArticle Views140Altmetric-Citations19LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (2 MB) Get e-Alerts Get e-Alerts

Molecular Semiconductors Based on Charge Transfer Complexes of Some Substituted Phenothiazines with Tetracyanoethylene

Abstract Molecular semiconductors based on charge transfer complexes of tetracyanoethylene (TCNE) with phenothiazines namely phenothiazine, 2-chlorophenothiazine, 2-acetylphenothiazine and 2-(trifluoro)methylphenothiazine have been prepared and characterized by elemental analysis, thermal, spectral and X-ray diffraction methods. The thermal decomposition behavior of these materials indicates that they are thermally stable up to about 100°C and then proceed to stoichiometric (1:1) weight losses corresponding to TCNE and phenothiazines. The stoichiometries were confirmed further from the combustion data. The existence of radical cations of phenothiazines and radical anions of TCNE were confirmed from their electronic and infrared spectral data. The preferential complexation with H-intra form of phenothiazines were indicated by their 1H NMR spectra. These materials were polycrystalline in nature and the powder X-ray diffraction data give their structures to be orthorhombic. The electrical conductivities are ...

Charge-transfer complexes of tetracyanoethylene with alkyl- and alkenylnaphthalenes and related compounds

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTCharge-transfer complexes of tetracyanoethylene with alkyl- and alkenylnaphthalenes and related compoundsJohn E. Frey, Anne M. Andrews, Scott D. Combs, Steven P. Edens, Jeffrey J. Puckett, Ronald E. Seagle, and Lori A. TorreanoCite this: J. Org. Chem. 1992, 57, 24, 6460–6466Publication Date (Print):November 1, 1992Publication History Published online1 May 2002Published inissue 1 November 1992https://doi.org/10.1021/jo00050a018RIGHTS & PERMISSIONSArticle Views167Altmetric-Citations22LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (884 KB) Get e-Alerts Get e-Alerts

Charge-transfer complexes of tetracyanoethylene with cycloalkanes, alkenes, and alkynes and some of their aryl derivatives

Caracteristiques spectrales et constantes d'associations des composes de transfert de charge du TCNE avec 89 hydrocarbures donneurs

Photochemistry of charge-transfer complexes of tetracyanoethylene and tetracyanoquinodimethane with aliphatic nitriles

Upon irradiation, tetracyanoethylene (TCNE) in acetonitrile gave 2-amino-1,1-dicyanopropene, while tetracyanoquinodimethane (TCNQ) in isobutyronitrile gave 1-(4-dicyanomethylphenyl)-2-methylpropane-1,1,2-tricarbonitrile; mechanisms involving electron transfer in which liphatic nitriles behave as electron donors are proposed.

Mechanism of oxidation of organopolysilanes by peroxy acids

To determine the regularities in the energy change of the highest occupied molecular orbital of a polysilane, which is localized in the Si-Si bond, the authors investigate the formation of charge-transfer complexes of tetracyanoethylene with some peralkylated and chlorosubstituted polysilanes. In oxidation of organopolysilanes by peroxybenzoic acid, the reaction is retarded with increasing values of I/sub 1/ /SUP D/ in the range of individually taken series of permethylated or chloro-substituted polysilanes. Replacement of an alkyl group at Si by a C1 atom leads to acceleration of the reaction, despite an increase of I/sub 1/ /SUP D/ .

Spectrophotometric studies of some charge-transfer complexes of tetracyanoethylene with poly(N-vinyl halogenocarbazoles)

The results and numerical analysis of measurements of absorption spectra of charge-transfer complexes of poly(N-vinyl halogenocarbazoles) with tetracyanoethylene are presented. The absorption bands result from donor–acceptor interaction together with values of equilibrium constants, enthalpy, and oscillators strengths of investigated complexes allowed us to conclude that isomerism of complexing took place. The influence of halogen substituents (mono- and disubstitution) in positions 3 and 6 of the carbazole ring (polymeric donor) on the spectral properties of its complexes was observed.

On the role of intramolecular vibrations in the nonradiative decay of excited charge-transfer states of molecular complexes

An attempt for a theoretical treatment of radiationless transitions from excited charge-transfer states in molecular complexes is made within the framework of the statistical limit of radiationless transitions theory. This work deals with the S 1 → S 0 internal conversion in charge-transfer complexes of tetracyanoethylene (an electron acceptor) with benzene and toluene and their perdeuterated analogues. A dominant role of the high-frequency totally symmetric intramolecular vibrational modes in the nonradiative decay of excited charge-transfer states is assumed (this was inferred from the experimentally observed deuterium isotope effect on radiationless S 1 → S 0 transitions). Calculated absolute rate constants for internal conversion are found to be in good agreement with experimental ones. The results of our calculations reflect very well the observed moderate deuterium isotope effect.

Photoaddition of the charge-transfer complexes of tetracyanoethylene–ether systems

Irradiation of the charge-transfer bands of the tetracyanoethylene–tetrahydrofuran, –tetrahydropyran, and –diethyl ether systems gave the corresponding 1 : 1 adducts.

Solvent effect on charge transfer complexes and their spectra—II

Abstract The thermodynamic and spectrophotometric properties of the charge transfer complexes of tetracyanoethylene with mesitylene and benzene are studied in cyclohexane, carbon tetrachloride, chloroform, dichloromethane and in addition the properties of the former complex are studied in benzene. The results show that these properties depend on the solvent. This important role of the solvent in changing both thennodynamic as well as spectrophotometric properties of these complexes is assumed to be due to the solvent interaction with tetracyanoethylene. An attempt is made to calculate the thermodynamic properties of the solvent-tetracyanoethylene interaction.

Ionic Photodissociation of Some Weak Charge Transfer Complexes of Tetracyanoethylene with n-Type Donor Molecules

Ionic Photodissociation of Some Weak Charge Transfer Complexes of Tetracyanoethylene with n-Type Donor Molecules

Charge Transfer Complexes of Tetracyanoethylene with [2. 2]Metacyclophane

[2.2]メタシクロファン(MCP)およびそのポリメチル誘導体とテトラシアンエチレン(TCNE)との電荷移動型錯合体について研究を行ない基礎的な知見が得られた。MCPはジクロルメタン溶媒中でTCNEと1:1の錯合体を形成し,そして486mμに極大をもつ新しい吸収帯が現われる。非環状化合物である1,2-ビス(p-エチルフェニル)エタンやm-キシレンとTCNEとの錯合体よりもレッドシフトしておりMCP錯体の安定化が示される。これはMCPにおいて,TCNEと錯体を形成しているベンゼン環へもう一つのベンゼン環からの寄与と見なされ,トランスアンニュラー効果によるもので,二つのベンゼン環の間の電荷移動構造が影響をもつものと思われる。MCP錯体の平衡定数の温度変化から結合エネルギーが-2.8kcal/mo1と見積られ,またMCPのイオン化ポテンシャル8.4eVと算出された。MCPに置換されるメチル基の数が増すにしたがいそれぞれ,CT帯はレッドシフトする。これらの錯合体について,パラシクロファンやベンゼンとTCNEとの錯合体の場合と比較検討した。

Charge-transfer complexes of tetracyanoethylene with acenaphthylene photodimers. The .omega. technique as an approach to transannular interaction

Charge-transfer complexes of tetracyanoethylene with acenaphthylene photodimers. The .omega. technique as an approach to transannular interaction