2,9-Diazadibenzoperylene and 2,9-Dimethyldibenzoperylene-1,3,8,10-tetratriflates: Key to Functionalized 2,9-Diazaperopyrenes

The synthesis of 2,9-diaza-1,3,8,10-tetratriflato-dibenzoperylene (DDP 3 a ) and corresponding 2,9-dimethyl-1,3,8,10-tetratriflato-dibenzoperylene (DBP 3 b ) has been developed at multigram scale via reduction of one of the industrially most important high-performance dyes, perylene-3,4,9,10-tetracarboxylic diimide (PTCDI), and of the corresponding dihydroxy peropyrenequinone precursor. The focus of this paper is on the reactivity pattern of 3 a as key intermediate towards highly functionalized 2,9-diazadibenzopyrelenes (DDPs) obtained via catalytic substitution of four triflate by aryl, heteroaryl, alkynyl, aminyl, and O-phosphanyl substituents. The influence of electron-donating substituents (OSiMe₃, OPt-Bu₂, N-piperidinyl), electron-withdrawing (OTf, 3,5-bis-trifluoromethyl-phenyl), and of electron-rich π-conjugated (2-thienyl, 4-tert-butylphenyl, trimethylsilyl-ethynyl) substituents on optoelectronic and structural properties of these functionalized DDPs has been investigated via XRD analyses, UV/Vis, PL spectroscopy, and by electroanalytical CV. These results were correlated to results of DFT and TD-DFT calculations. Thus, functionalized DPPs with easily tunable HOMO and LUMO energies and gap became available via a new and reliable synthetic strategy starting from readily available PTCDI.     

铜酞菁同质多晶现象的研究及其超细粒子的制备

采用路易斯酸配位法溶解了铜酞菁,并对路易斯酸溶解铜酞菁的机理进行了简单讨论,同时研究了溶解过程中不同溶剂对铜酞菁晶型的影响.最后,用路易斯酸溶解配位法和微射流纳米分散技术相结合的方法成功制备了铜酞菁超细粒子,并用激光粒度仪、原子力显微镜、紫外可见分光光度计对超细粒子的粒径和吸收光谱进行了表征.     

On the electronic structures and spectroscopic properties of polyyne and its derivatives

We present a theoretical study on the electronic structure and spectroscopic properties of polyyne and its derivatives using periodic density functional theory study and semiempirical ZINDO/s methods. The electronic density of states were calculated, which indicates that polyyne behaves like a semiconductor and the insertion of aromatic groups into the polymer chain gives rise to significant metallic characters in the materials. The vibrational and UV–vis spectra of polyyne and its derivatives were simulated using a monomer or oligomer model. The effects of aromatic insertion into polyyne chain on their electronic and spectroscopic properties were discussed. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2008     

Modifications of 5,12-dihydroindolo[3,2-a]carbazole scaffold via its regioselective C2,9-formylation and C2,9-acetylation

The effective approaches for regioselective double formylation and acetylation of 5,12-dialkyl-6,7-diaryl-substituted 5,12-dihydroindolo[3,2-a]carbazoles by their treatment with dichloromethyl methyl ether in the presence of SnCl₄ or with acetyl chloride in the presence of AlCl₃ to afford the 2,9-diformyl or 2,9-diacetyl derivatives, respectively, were developed. Furthermore, new 2,9-bis(2,2-dicyanovinyl) derivatives were synthesized by the Knoevenagel condensation of diformyl-containing substrates with malononitrile, when new 2,9-bis(quinoxaline-2-yl)- and 2,9-bis(benzo[g]quinoxaline-2-yl) derivatives were formed via microwave-promoted oxidation of diacetyl-containing substrates with SeO₂ to the corresponding diglyoxals, followed by the reaction of these intermediates with o-phenylendiamine or 2,3-diaminonaphthalene, respectively. The basic optical and electrochemical properties of some 5,12-dihydroindolo[3,2-a]carbazoles were investigated.     

Structures, electronic properties and solid state luminescence of Cu(I) iodide complexes with 2,9-dimethyl-1,10-phenanthroline and aliphatic aminomethylphosphines or triphenylphosphine

The luminescent complexes of triphenylphosphine and two interesting aminomethylphosphines: P(CH(2)N(CH(2)CH(2))(2)NCH(3))(3) and P(CH(2)N(CH(2)CH(2))(2)O)(3) with copper(I) iodide and 2,9-dimethyl-1,10-phenanthroline (dmp): [CuI(dmp)PPh(3)], [CuI(dmp)P(CH(2)N(CH(2)CH(2))(2)NCH(3))(3)] and [CuI(phen)P(CH(2)N(CH(2)CH(2))(2)O)(3)] are presented in this work. These complexes were characterized in solution by means of NMR spectroscopy and their structures were crystallographically determined in the solid state. All complexes crystallize as the discrete dimers bound by π-stacking interactions between dmp rings. The coordination geometry about the Cu(I) centre is pseudo-tetrahedral showing small flattening and large rocking distortions. The investigated compounds exhibit intense orange photoluminescence in the solid state (emission peaks at r.t.: λ(max) = 588-592 nm; τ = 1.7-2.2 and 6.4-10.0 μs; at 77 K: λ(max) = 605-612 nm; τ = 4.8-6.5 and 32-47 μs), which is several orders higher than the luminescence of the analogous complexes with 1,10-phenanthroline (phen). Electronic and structural properties of the [CuI(dmp/phen)PR(3)] complexes were characterized using DFT methods to interpret their photophysics. On the basis of TDDFT calculations the broad CT bands observed in UV-Vis spectra are interpreted as the two mixed transitions from σ(CuI) bond with a small admixture of σ(CuP) bond to π* phen or dmp ligand: (MX,MPR(3))LCT, while the emissions most probably occur from two triplet states which are in thermal equilibrium.     

The electronic structure and properties of pyrazine,its cation,and anion

Gaussian orbital LCAO MO calculations are reported for pyrazine in its ground and first excited triplet state, together with calculations on its anion and cation. Energies, population analysis indices, and one-electron properties are compared across the series in order to investigate the differences in electron distribution.     

硫化聚乙炔结构对其电子性能的影响

本文用硫原子和共轭多烯的复合物模拟硫化聚乙炔结构, 并采用一维紧束缚的LCAO-SCF-MO法, 探讨了硫化聚乙炔结构对其电子性能的影响, 揭示出影响的原因, 确定了最佳结构, 为实验合成提供了理论依据。     

Reinvestigation of the GaMn structure and theoretical studies of its electronic and magnetic properties

The crystal structure of the binary gallide compound GaMn is reinvestigated using X-ray diffraction. The structure is quite different from that proposed previously. Although GaMn is reported to crystallize with the Al₈Cr₅ structure type, space group R3m, we found that the centrosymmetric space group , with a=12.605(2) Å and c=8.0424(11) Å, was more accurate. Moreover, the atomic positions and the atomic displacement parameters, which are missing in the previous study, are now refined. Thereafter, band structure calculations have been performed using the TB-LMTO-ASA method to understand the electronic and magnetic properties of this compound. Analyses from the band structure, the density of states and the magnetic moments obtained using spin-polarized calculations show the stability of two different magnetic models relative to the nonmagnetic one.     

苯并噻二嗪衍生物电子结构和非线性光学性质的研究

运用量子化学PM3方法，对苯并噻二嗪几种衍生物的几何构型、电子结构和前线分子轨道成分进行了分析，研究了电荷分布规律。同时，基于体系中电子转移的特点，利用有限场FF方法探讨了其非线性光学性质的变化。结果表明，苯并噻二嗪分子具有较好的二阶非线性光学性质，并可能成为一类良好的光学材料。     

Structural and electronic properties of heptachlor

In this work, the molecular geometry of heptachlor is investigated using ab initio HF, DFT, LDA, and GGA methods. The natural bond orbital (NBO) analysis is performed at the B3LYP/6-311++G(d,p) level of theory. The first order hyperpolarizability β_total, the mean polarizability Δα, the anisotropy of the polarizability Δα, and the dipole moment μ, are calculated by B3LYP/6-311++G(d,p) and HF/6- 311++G(d,p) methods. The first order hyperpolarizability (β_total) is calculated based on the finite field approach. UV spectral parameters along with HOMO, LUMO energies for heptachlor are determined in vacuum and the solvent phase using HF, DFT, and TD-DFT/B3LYP methods implemented with the 6-311++G(d,p) basis set. Atomic charges and electron density of heptachlor in vacuum and ethanol are calculated using DFT/B3LYP and TD-DFT/B3LYP methods and the 6-311++G(d,p) basis set. In addition, after the frontier molecular orbitals (FMOs), the molecular electrostatic potential (MEP), the electrostatic potential (ESP), the electron density (ED), and the solvent accessible surface of heptachlor are visualized as a results of the B3LYP/6-311++G(d,p) calculation. Densities of states (DOS), the external electric field (EF) effect on the HOMO-LUMO gap, and the dipole moment are investigated by LDA and GGA methods.     

Molecular structure of 2,9-dioxo-1,3,8,10-tetraoxa-2,9-dithiacyclotetradeca-5,12-diyne

Conclusions The heterocycle 2,9-dioxo-1,3,8,10-tetraoxa-2,9-dithiacyclotetradeca-5,12-diyne has a conformation of C₂ symmetry in the crystal; the acetylene fragments intersect at an angle of 20.8°. The bond lengths and the endocyclic valence angles are close to their standard values.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2750–2753, December, 1987.     

羿喹啉及其衍生物的电子结构与缓蚀性能关系的研究

本文在30℃, 1.0mol.dm^-3 HCl溶液中用电化学方法测定了异喹啉及其羟基,羧基衍生物对Fe电极的缓蚀效率。并用HMO和CNDO/2方法计算了这些化合物的量子化学参数, 发现异喹啉及其衍生物分子中氮原子电荷和π净电荷越小, 缓蚀性能越好; 随着这些化合物异喹啉环中吡啶环上原子电荷之和的增大, 缓蚀性能提高; 吡啶环亲核前沿电荷与缓蚀效率有很好的线性关系, 提出了这类缓蚀剂分子可能呈平卧方式吸附于金属电极表面, 从而起缓蚀作用, 预测了五个新分子的缓蚀性能。     

A relativistic study of the electronic and magnetic properties of cerocene and thorocene and its anions

In this study, we evaluated the importance of the relativistic effects on the optical and magnetic properties of cerocene and thorocene and its corresponding anions. The optimized molecular structures show D(8h) symmetry for all systems, in good agreement with the experimental data. Atomic charges were analyzed using different approaches (Mulliken, AIM, multipole, and NBO), and the results suggest that the net charge on the thorium is greater than on the cerium atom; however, none of the methodologies were able to predict the expected net charge Ce(III) and Th(IV) atoms. However, by an energy decomposition analysis, a significant electrostatic, ionic, interaction, ~58% and ~61%, was found between the metal and the COT(2-) rings, respectively. The calculated electronic excitations are underestimated in comparison with the experimental data, while the calculated EPR g-tensors are in agreement with previous theoretical and experimental data. Besides, the NICS analysis shows an increased ring electron delocalization due to the lanthanide and actinide metals.     

Monoclinic Low-Temperature Polymorph of Cesium Nitrate

A new CsNO₃ polymorph with space group P2₁/c, Z = 4, a = 4.5699(9) Å, b = 11.1871(10) Å, c = 9.1484(18) Å, β = 131.24(3)° has been prepared by crystallization from a mixture of water and DMSO. Flat triangles NO₃ are located in the (010) and (020) planes between the layers formed by coordination polyhedra of Cs atoms in the (040) plane. In contrast to the previously known low-temperature polymorph, the new modification is characterized by the crystal equivalence of all Cs and NO₃ groups.     

Configuration analysis and electronic states properties

The excited-states electronic properties of unsaturated small-ring hydrocarbons with four- and six--electrons have been studied by the Molecules in Molecules method and compared with experimental data and PPP results interpreted through a configuration analysis procedure. The results show that the MIM method is applicable with good reliability.

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Zusammenfassung Die elektronischen Eigenschaften der angeregten Zustände von ungesättigten kleinen Kohlenwasserstoffringen mit vier und sechs -Elektronen wurden mit Hilfe der Molekül- im-Molekül-Methode untersucht und die Ergebnisse mit experimentellen Daten und PPP Resultaten, die durch eine Konfigurationsanalyse interpretiert wurden, verglichen. Die Ergebnisse zeigen, daß die MIM-Methode mit großer Zuverlässigkeit anwendbar ist.

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Financial aid from the Italian C.N.R. is gratefully acknowledged.     

Luminescent bichromophoric spiroindolones--synthesis and electronic properties

Novel bichromophoric spirocyclic indolones have been synthesized by an insertion-coupling-isomerization-Diels-Alder domino reaction. The emission colors are strongly affected by the substituents: N-Boc leads to intense blue fluorescence, N-dansyl causes turquoise emission, whereas a 1-anthryl substituent on the butadiene results in yellow luminescence. The latter behavior is rationalized by TDDFT computations as a result of significant geometrical changes.     

Structural and electronic properties of borazine cyclacenes

The structural and electronic properties of borazine cyclacenes (BNn) have been investigated by performing semiempirical molecular orbital self-consistent field calculations at the level of AM1 method within the RHF formulation. It has been found that as the number of borazine rings increases in the arenoid belt the structures become more exothermic.