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Although diradicals and azaacenes have been greatly attractive in fundamental chemistry and functional materials, the isolable diradical dianions of azaacenes are still unknown. Herein, we describe the first isolation of pyrene‐fused azaacene diradical dianion salts [(18‐c‐6)K(THF)2]+[(18‐c‐6)K]+? 1 2?.. and [(18‐c‐6)K(THF)]2+? 2 2?.. by reduction of the neutral pyrene‐fused azaacene derivatives 1 and 2 with excess potassium graphite in THF in the presence of 18‐crown‐6. Their electronic structures were investigated by various experiments, in conjunction with theoretical calculations. It was found that both dianions are open‐shell singlets in the ground state and their triplet states are thermally readily accessible owing to the small singlet–triplet energy gap. This work provides the first examples of crystalline diradical dianions of azaacenes with considerable diradical character.  相似文献   

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An arginine‐substituted zinc phthalocyanine (ArgZnPc) capable of disaggregating at high concentrations in polar non‐aqueous solvents through concentration‐driven hydrogen bond type transformation has been prepared. The ArgZnPc was prepared through a guanidine‐meditated self‐catalytic ester hydrolysis reaction. The concentration‐driven disaggregation of ArgZnPc was confirmed by UV‐Vis absorption spectra, fluorescence emission spectra and lifetimes, and singlet oxygen quantum yield data.  相似文献   

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《化学:亚洲杂志》2017,12(16):2121-2126
Two novel diazadioxaacene derivatives ( ADOP and ADOQ ) have been successfully synthesized and characterized. Their single crystal analyses disclose that molecule ADOP forms a twisted topology configuration, whereas ADOQ adopts reclining‐chair architecture. Both of them emit strong blue fluorescence in organic solvents. Moreover, they can self‐assemble to form regular nanobelts and nanowires, respectively, via a simple surfactant‐assisted method.  相似文献   

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Phthalocyanine compounds of novel type based on a bridged bis‐ligand, denoted “intracavity” complexes, have been prepared. Complexation of clamshell ligand 1,1′‐[benzene‐1,2‐diylbis(methanediyloxy)]bis[9(10),16(17),23(24)‐tri‐tert‐butylphthalocyanine] (clam,tBuPc2H4, 1 ) with lanthanide(III) salts [Ln(acac)3] ? n H2O (Ln=Eu, Dy, Lu; acetylacetonate) led to formation of double‐deckers clam,tBuPc2Ln ( 2 a – c ). Formation of high molecular weight oligophthalocyanine complexes was demonstrated as well. The presence of an intramolecular covalent bridge affecting the relative arrangement of macrocycles was shown to result in specific physicochemical properties. A combination of UV/Vis/NIR and NMR spectroscopy, MALDI‐TOF mass‐spectrometry, cyclic voltammetry, and spectroelectrochemistry provided unambiguous characterization of the freshly prepared bis‐phthalocyanines, and also revealed intrinsic peculiarities in the structure–property relationship, which were supported by theoretical calculations. Unexpected NMR activity of the paramagnetic dysprosium complex 2 b in the neutral π‐radical form was observed and examined as well.  相似文献   

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《化学:亚洲杂志》2018,13(19):2881-2890
A set of 1,8‐naphthalimide (NPI)‐substituted 4,4‐difluoroboradiaza‐s‐indacene (BODIPY) dyads 1 a – 1 c were designed and synthesized by the Pd‐catalyzed Sonogashira cross‐coupling reaction of ethynyl substituted NPI 1 with the meso‐, β‐, and α‐halogenated BODIPYs a , b , and c , respectively. The BODIPY 1 c exhibits redshifted absorption, which suggests better electronic communication with substitution at the α‐position of BODIPY compared with at the meso and β positions, which was further supported by time‐dependent DFT calculations. The optical band gap follows the order 1 a > 1 b > 1 c . The single‐crystal X‐ray structures of dyads 1 a – 1 c are reported, which reflect planar orientations of the BODIPY units with respect to the NPIs. The DFT‐optimized structures show good correlation with the experimental data obtained from the single‐crystal X‐ray structures. The packing diagram of 1 a shows a sheet‐like arrangement, 1 b forms a ladder‐like structural motif, and 1 c forms a complex 3D structural arrangement. The dyads 1 a – 1 c show low cytotoxicity (IC50>100 μm ). The confocal microscopy studies with HeLa and A375 cells (when treated with dyads 1 a – 1 c ) show that all the dyads easily enter the cell membrane and show significant multicolor intracellular fluorescence covering the entire visible range with clear emissions in blue, green, and red channels.  相似文献   

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In this account, the synthesis and applications of pyrene‐fused acenes, as well as pyrene‐fused azaacenes, have been carefully reviewed. Moreover, the synthetic methods involving two key synthons (different lengths of dienes and ynes) have been included. Furthermore, the “clean reaction” strategy has been introduced for the preparation of pyrene‐fused acenes with a single terminal‐pyrene unit from tetracene to octacene, as well as for the synthesis of pyrene‐fused octatwistacenes and nonatwistacenes with double terminal‐pyrene units. Similarly, the synthons and the synthetic methods for pyrene‐fused azaacenes have also been summarized. The applications of pyrene‐fused acenes and pyrene‐fused azaacenes have been included.  相似文献   

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Pi ‐extended polyaromatics tend to exhibit improved electronic properties with respect to the intrinsic structures. Herein, the rational design of a π‐extended diindole‐fused diazapentacenone ( IP ), with a nine‐ring‐fused core, obtained by applying an intramolecular Friedel–Crafts diacylation synthetic routine, is reported. The chemical structure, physical properties, and morphology of IP were fully characterized. Serving as an organic cathode material for a lithium‐ion battery, the as‐prepared nanorods of π‐extended IP display higher conductivity and superior electrochemical performance than those of the naked diazapentacenone without diindole fusion.  相似文献   

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A highly soluble pyrene‐fused undecacene is realized by end‐capping the rectilinear aromatic π‐plane with triptycenylene units. Besides the good solubility, the compound shows a high tendency to crystallize. Two polymorphs from dichlorobenzene and chloroform are described. In the polymorph from chloroform, half of the molecules are strongly bent out of the π‐plane by 26.4°.  相似文献   

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A series of four phenanthro[4,5‐fgh]quinoxaline‐fused subphthalocyanine derivatives 0 – 3 containing zero, one, two, and three phenanthro[4,5‐fgh]quinoxaline moieties, respectively, were isolated from the mixed cyclotrimerization reaction of 2,9‐di‐tert‐butylphenanthro[4,5‐fgh]quinoxaline‐5,6‐dicarbonitrile with 4,5‐bis(2,6‐diisopropylphenoxy)phthalonitrile and characterized by a series of spectroscopic methods including MALDI‐TOF mass, 1H NMR, electronic absorption, magnetic circular dichroism (MCD), and fluorescence spectroscopy. The molecular structures for the compounds 0 and 2 were clearly revealed on the basis of single‐crystal X‐ray diffraction analysis. Their electrochemical properties were also studied by cyclic voltammetry. In particular, theoretical calculations in combination with the electronic absorption and electrochemical analyses revealed the significant influence of the fused‐phenanthro[4,5‐fgh]quinoxaline units on the electronic structures.  相似文献   

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合成了一种新型不对称Schiff碱铜前体配合物KCuL和一种化学组成为[(CuL)2Mn (H2O)2]·0.5CH3OH·0.5CH3OH的顺式异三核配合物,并通过元素分析、IR谱的方法对其进行了表征(其中H3L = N-(2-{[(1E)-(5-氯-2-羟基苯基)亚甲基]胺基}乙基)-2-羟基苯甲酰胺)。利用X-射线单晶衍射方法对三核配合物的晶体结构进行了测定。该三核配合物的每一晶胞单元含有一个顺式中性异三核分子和两个无序的甲醇分子。中心锰离子Mn2+处于O6形成的变形八面体几何构型,而两个配阴离子[CuL]-在Mn2+周围呈顺式排布。磁性表明该三核配合物不仅具有分子内反铁磁作用,而且三核单元之间具有弱的铁磁交换作用,磁参数分别为J = -12.1 cm-1, g = 2.20 and zj¢ = 1.37 cm-1.  相似文献   

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π‐Extended thiadiazoles 4 – 8 fused with various electron‐donating heteroaromatic moieties have been designed and synthesized. Just like thiadiazoles 1 – 3 synthesized previously, 4 – 8 exhibit intramolecular charge‐transfer (CT) interactions, moderate‐to‐good fluorescence quantum yields of up to 0.78, and electrochemical amphoterism. In comparison with 1 – 3 , the benzannulation in thiadiazoles 4 – 7 moderately extends the π conjugation and significantly increases the stability of the cationic species formed upon electrochemical oxidation. The fluorescence quantum yields increase remarkably from 3 to 6 and 7 due to the efficient suppression of nonradiative intersystem crossing resulting from the benzannulation. The properties of 4 – 8 strongly reflect the different species annulated to the pyrrole rings, namely benzothiophene, naphthalene, and benzofuran. Eleven crystals, including poly‐ and pseudopolymorphic crystals of 1 ( 1‐Crys. ( Y ) and 1‐Crys. ( G )), 2 ( 2‐Crys. ( O ) and 2‐Crys. ( G )), 4 ( 4‐Crys. ( O ) and 4‐Crys. ( G )), and 6 ( 6‐Crys. ( O ) and 6‐Crys. ( G )), were obtained and characterized by X‐ray crystallography. The fluorescence colors and efficiencies are distinct for each poly‐ and pseudopolymorph of 1 , 2 , 4 , and 6 . It has been suggested that both the extent of the electronic interactions in the π‐stacked dimers and the presence of excitonic interactions originating in the 1D face‐to‐face slipped columns affect the fluorescence wavelengths of the poly‐ and pseudopolymorphs.  相似文献   

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A series of octa‐substituted metal phthalocyanines [MPc(OC5H11)8] (M = Co, Ni, Cu, Zn, Pc = phthalocyaninato, (OC5H11)8 = iso‐pentoxy) were obtained from condensation of iso‐pentoxy phthalonitrile in the presence of DBU in n‐pentanol. The compounds were characterized using elemental analysis, IR, and UV/Vis spectra. The crystal structures of all compounds except M = Zn were determined by X‐ray diffraction methods. It was found that the distortion of Pc skeleton come of not only the intra‐molecular steric congestion of bulky substituents, but also the slipped overlaps of the closest molecules. The relations of some bond lengths of the Pc's skeleton to the substituents and central metal atom, as well as the spectroscopic properties are discussed.  相似文献   

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本文采用水热法合成了一个新的金属有机-无机杂化化合物 [Cu4(phen)4(HPO4)2(H2O)2(OH)2][HPMo12O40]·H2O (1) ( phen=邻菲咯啉)。通过元素分析、红外光谱、热重分析、X-射线单晶衍射对其进行了结构表征。化合物1是由四核铜磷酸盐、Keggin阴离子和晶格水分子组成。四核铜磷酸盐和多阴离子之间通过弱的M…O相互作用形成二维结构(M=Cu, Mo), 该二维结构通过氢键和π-π相互作用形成三维超分子框架,还对化合物1的电化学和电催化性质进行了研究。  相似文献   

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We prepared two heterooligomeric arrays based on free base/metalloporphyrins at axial positions and a metalloid phthalocyanine as a basal scaffolding unit by using the axial‐bonding capabilities as well as the known oxophilicity of dihydroxytin(IV) phthalocyanine. Both heterotrimers were completely characterized by elemental analysis, MALDI‐TOF MS, and 1H NMR (one‐ and two‐dimensional), UV/Vis, and fluorescence spectroscopy as well as cyclic voltammetry. The ground‐state properties indicate that there is minimal π–π interaction between the macrocyclic units. The excited‐state properties show that there is electronic energy transfer competing with photoinduced electron transfer from the singlet state of the axial porphyrin to the central metalloid phthalocyanine and a photoinduced electron transfer from the ground state of the axial porphyrin to the singlet state of the central metalloid phthalocyanine.  相似文献   

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The synthesis and characterization of a new type of chromophore, namely PePc consisting of a central phthalocyanine core and four fused perylene–bisimide (PBI) units is described for the first time. The entire architecture represents a highly extended conjugated heterocyclic π‐system with C4h symmetry. In order to guarantee pronounced solubility in organic solvents the corresponding PBI units were bay‐functionalized with tert‐butylphenoxy substituents. Next to the metal‐free macrocycle, PePcH2, also metallated macrocycles PePcM (M=Zn, Ni, Pb, Ru, Fe) were synthesized. The extensive fusion of the corresponding aromatic building blocks to the very large extended π‐system leads to a very narrow HOMO–LUMO gap and as a consequence to transparency in the visible but light absorption in the NIR region. Significantly, the azomethine N‐atoms N1?N4 of PePcM and PePcH2 are highly basic. The corresponding tetraprotonated systems can only be deprotonated with very strong non‐nucleophilic bases such as phosphazene bases. In the protonated forms PePcMH44+ and PePcMH64+ the absorption maximum is shifted back to the visible region due to the loss of conjugation. The experimental findings were corroborated with quantum mechanical calculations.  相似文献   

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《中国化学》2017,35(9):1437-1444
A series of spiro‐oxadiazoles were synthesized from 1,4:3,6‐dianhydro‐D ‐fructose and hydrazides via a stereo‐ selective two‐step reaction sequence. The structures of newly synthesized compounds were established by spectral analysis. The absolute configuration of compound 2a was further confirmed by single crystal X‐ray analysis. All the synthesized compounds were screened for their in vitro antitumor activity, showing that these compounds have poor inhibitory activities against A549, MGC‐803 tumor cells.  相似文献   

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