On the electronic states of macrocycles of the extended porphyrin family and their coordination compounds

The electronic absorption spectra of Ni, Zn and Mg hemiporphyrazine derivatives are presented and discussed together with theoretical results obtained by INDO/S computations. The absorption spectra of all the metal derivatives show marked red shifts of the lowest energy absorption bands with respect to those of the metal free hemiporphyrazine. The possible explanation that in metal derivatives low lying excited states with a fully conjugated π electron system are present is supported by theoretical computations.     

一步法合成一系列新型含嘧啶基团的共轭大环化合物

本文利用化合物3,5-二(5-溴-嘧啶基)-1-叔丁基苯(2)与3,5-二(4,4,5,5-四甲基-1,3,2,-二氧杂戊硼烷-2-基)-1-叔丁基苯(3)作为单体在Pd(PPh₃)₄ 催化下,经一步Suzuki交叉偶联反应合成得到一系列新型含嘧啶基团的共轭大环化合物1(1_8mer-1_12mer)。这些化合物的结构均通过₁H NMR和MALDI-TOF mass表征,并利用紫外,荧光光谱对其光学性能进行了初步的研究。实验表明这种一步法可以高效地制备一系列具有不同环大小的共轭大环化合物,这为进一步制备类似的共轭大环化合物提供了新的合成策略。     

Synthesis, electrochemical and photophysical properties of β-carboxy triaryl corroles

An unswerving one-pot conversion of 3-formyl-5,10,15-triaryl substituted corroles and their copper(III) derivatives to the corresponding 3-carboxy-5,10,15-triaryl substituted corroles was achieved by adopting mild reaction conditions by using hydroxylamine hydrochloride and phthalic anhydride. All these substituted carboxy corroles were completely characterized by using Mass, CHN analysis, IR, ¹H NMR, UV-vis., Fluorescence spectroscopies, and cyclic voltammetry. Both the absorption maxima and emission maxima of carboxy corroles were red shifted by 5-13 nm. The LUMO level of these corroles is above the TiO₂ conduction band and HOMO level was below the redox electrolytes. These β-carboxy corroles confined with may find applications as sensitizers in dye-sensitized solar cells.     

Cobalt(III) corrole-tethered semiconducting graphdiyne film for efficient electrocatalysis of oxygen reduction reaction

Inspired from nature, transition metal porphyrins and corroles have been designed and synthesized for electrocatalytic oxygen reduction reaction (ORR). However, the efficiency is limited by their low conductivity and thus carbonization is usually required. Herein, we report a new strategy by covalently linking cobalt(III) corrole and cobalt(II) porphyrin onto a semiconducting fluoro-graphdiyne (F-GDY) film through nucleophilic substitution reaction. The crystalline F-GDY film was prepared by Glaser-Hay coupling at the water/dichloromethane interface, followed by ultrasonic-assisted exfoliation in liquid. The Co(III) corrole-tethered F-GDY material exhibited excellent four-electron ORR activity, with a half-wave potential of 0.875 V (vs reversible hydrogen electrode). It also displayed high discharge performance and capacity in a zinc-air battery device, superior to the commercial Pt/C. Our study provides a pyrolysis-free approach toward biomimetic catalysts for efficient small molecule activation.     

Synthesis of isocorrole and the higher homologues

Bis(azafulvene) derivative of gem-dimethyldipyrrylmethane reacted with 2,2′-bipyrrole under neutral conditions without catalyst to give a mixture of expanded isocorroles in ca. 50% total yields. GPC separation gave eleven porphyrinoids containing 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, and 44 units of pyrrole.     

咔咯钴(Ⅲ)配合物与DNA的相互作用及抗肿瘤活性

合成了10-(4-羟基苯基)-5,15-二(五氟苯基)咔咯钴(Ⅲ)配合物(1-Co)和10-(4-吩噻嗪苯基)-5,15-二(五氟苯基)咔咯钴(Ⅲ)配合物(2-Co),并采用核磁共振波谱、质谱和紫外-可见光谱等对其结构进行了表征,利用紫外光谱、荧光光谱、圆二色谱、黏度测试和琼脂糖凝胶电泳等技术研究了配合物1-Co和2-Co与小牛胸腺DNA(ct-DNA)之间的相互作用.结果表明,配合物1-Co和2-Co与DNA之间的作用模式为外部结合,且在光照下均能引发DNA断裂.细胞毒性实验结果表明,配合物1-Co和2-Co具有很低的暗细胞毒性,但在光照条件下均能有效抑制H460,He La,A549等肿瘤细胞株增殖,表明配合物1-Co和2-Co在光动力治疗中具有潜在的应用价值.细胞核染色和线粒体膜电位检测结果表明,在光照条件下配合物2-Co可能是通过氧化损伤线粒体的途径抑制肿瘤细胞增殖.     

Facile synthesis and photophysical properties of 1,2-phenylene-bridged porphyrin dimers

Facile synthesis of 1,2-phenylene-bridged porphyrin dimers via Pd-catalyzed cross-coupling reaction and their photophysical properties only moderately perturbed by inter-porphyrin electronic interactions are reported.     

Multi-gram synthesis of a porphyrazine platform for cellular translocation, conjugation to Doxorubicin, and cellular uptake

We report the synthesis of the near infrared (NIR) fluorescent porphyrazine (Pz) 285, with pendant hydroxyl groups, as a non-toxic platform for delivery of conjugated chemotherapeutic agents to tumor cells. Conjugation of Pz 285 to Doxorubicin via an acid labile linker and initial biological studies are reported.     

溶剂对镓Corrole光谱性质的影响

合成了一系列周边取代的Corrole(1, 2, 3, 4)及其镓配合物1-Ga(Py)、2-Ga(Py)、3-Ga(Py)、4-Ga(Py),通过核磁共振氢谱(¹H NMR), 紫外-可见光谱, 电喷雾离子质谱(ESI-MS)的方法对其进行了表征. 研究了不同溶剂对这一系列自由Corrole 及镓Corrole 的紫外-可见(UV-Vis)吸收光谱, 稳态荧光和时间分辨荧光光谱, 将获得的荧光衰减动力学曲线采用单指数拟合并进行解卷积处理获得荧光的寿命值. 非（弱)极性溶剂对镓Corrole 紫外光谱的影响服从Bayliss 方程, 且镓Corrole 非辐射能量损失hc(ν¹_A-ν_F)与F(n)呈线性相关.     

失水山梨醇单月桂酸酯的一步法合成

失水山梨醇单月桂酸酯(商品名Span20)用途广泛[1 4]。传统方法[5]生产出的产品色泽深、副产物多、单酯质量分数低、熔融状态下多呈浑浊状态、质量不稳定,仅能用于石油、采矿和纤维等行业,用于食品、医药、化妆品的这类产品绝大部分依赖进口。本文以山梨醇和月桂酸为原料,采用一步法合成的目标产物为乳白色,单酯质量分数大于90%。并对合成方法进行了对比,探讨了各主要影响因素对目标产物色泽和三项指标(酸值、羟值、皂化值)的影响。梨醇的醚化和酯化反应产物是一个复杂的混合物:不仅有单酯及其异构体,还会存在其它二酯、多酯及相应异构…     

Electronic and structural properties of the metalloporphyrin structural isomers: semiempirical AM1 and PM3 calculations

Semiempirical calculations using AM1 and PM3 have been performed on the zinc(II) and magnesium(II) complexes of nine structural isomers of tetrapyrrole macrocycles such as porphyrin, porphycene, corrphycene and hemiporphycene, N-confused porphyrin and other isomers that have not been synthesized. The optimized geometry and the bond parameters obtained compare favorably with results obtained from X-ray and spectral studies. Heats of formation, ionization potentials, HOMO-LUMO energy differences, dipole moments, and the splitting of HOMOs and LUMOs of the metal complexes of each of these isomers are also reported and compared with experimental results. The “four-orbital model” of Gouterman remains valid for the investigated structural isomers. The present study represents an unusually appropriate opportunity to study, via molecular orbital methods, the interaction between various metal ions, and the electronic and geometrical environment of the central cavity of the closely related isomeric macrocycles. The major outcome of this study is the verification of the expected differential behavior of metal ions employed in the present study as a sophisticated probe of cavity properties which also suggests that this procedure can be extended to other metal complexes. This study also serves as an interesting prototype for more elaborate ab initio calculations. However, such calculations on the presently investigated macrocyclic systems may have to be performed at a higher level than MP2 or DFT to account for the unusual delocalization, as suggested by a recent study by Schaefer and co-workers on delocalized [10]annulene (H.M. Sulzbach, H.F. Schaefer, W. Klopper and H.P. Luthi, J. Am. Chem. Soc., 118 (1996) 3519).     

One-step synthesis of 2-indolylalkylamines

An efficient one-step synthesis of 2-indolylalkylamines was proposed. The synthesis involves the Fischer reaction of phenylhydrazine with cyclic imines containing a CH₂ group in the α-position or with amino ketones containing two CH₂ groups in the α-position with respect to the C=O group.     

Ethynyl-bridged porphyrin-corrole dyads and triads: Synthesis,properties and DFT calculations

Ethynyl-bridged porphyrin-corrole dyads and triads were synthesized by using Pd(0) mediated coupling reactions and their structures were characterized by NMR, FT-IR, UV/Vis and fluorescence techniques. Besides spectroscopic techniques, computational studies at B3LYP/6-311G(d,p) level of DFT were also used to elucidate the minimum energy geometries and the molecular orbital characteristics of the new dyads and triads. DFT calculations pointed out the presence of charge separated donor-acceptor property between macrocycles of dyads and triads, and the emission studies indicated an excited state interaction between macrocycles, and energy transfer from the porphyrin to the corrole unit.     

Serendipitous synthesis of trimetallic porphyrazine triads

We report the synthesis and characterization of structurally unusual porphyrazine triads with three macrocycles bound to a central pyrazine core. These trimacrocyclic complexes were accidentally discovered during studies on the peripheral metallation of porphyrazinediamines. The crystal structure of the tri-zinc porphyrazine triad is described and the spectroscopic properties including electronic absorption spectra of this complex and the corresponding magnesium, free-base, and copper derivatives are reported.     

Unusual hydrothermal synthesis of a heteroaromatic macrocyclic complex

Hydrothermal treatment of 2,3-bis(2′,6″-bipyridyl)quinoxaline, molybdenum trioxide, cupric acetate and water unexpectedly forms the Cu(II) complex of a planar, macrocyclic 2-acyl-6,2′-bipyridyl dimer, imbedded within a copper benzotrizolate-octamolybtate matrix. X-ray crystallographic characterization of this material, and scalar relativistic ZORA DFT modeling of the complex dication are presented.     

One-step synthesis of dipyrromethanes in water

In this communication we describe the first results of an efficient synthesis of β-free-dipyrromethanes in water. This new method affords very pure products in moderate to high yields, using a cheap, non-toxic, environment friendly solvent, in a one-step procedure from pyrrole and carbonyl compounds, needing little or no work up procedures.     

Hexazamacrocycle assisted sensing of silver ion through facile synthesis of silver nanoparticles

The ease of generation of silver nanoparticles by using hexazamacrocycle ligand, L1 is utilized for the visual detection of the presence of silver ions at lower concentrations.     

A theoretical study of porphyrin isomers and their core-modified analogues: cis-trans isomerism, tautomerism and relative stabilities

Semiempirical (AM1 and PM3) and density functional theory (DFT) calculations were performed on about 50 porphyrin isomers with 25 each of 1,2 (syn) and 1,3 (anti) tautomeric forms. The corresponding oxa-and thia-core-modified analogues were also computed. The variations of relative energies and stabilities of the core-modified analogues were compared with parent porphyrin1 and the corresponding oxa-and thia-analogues. The trends in relative energies are not significantly changed while going from parent system to oxa-and thia-core-modified porphyrins in case of bothsyn andanti tautomers. Isomers of types [2·2·0·0], [3·0·1·0], [3·1·0·0], and [4·0·0·0] are destabilized due to the absence of methine bridge, which results in angle strain for tetrapyrroles. Isomers having [2·1·1·0], [2·1·0·1], [2·0·2·0] and [2·2·0·0] connectivity, the Z isomers, are more stable compared to the correspondingE isomers in bothsyn andanti forms of parent and core-modified analogues.     

Improved synthesis of sterically encumbered multibrominated corroles

Efficient and easily reproducible synthesis of sterically hindered multibrominated corroles is achieved via dipyrromethane-aldehyde condensation reaction in good yields.Boron trifluoride dietherate（BF_3-Et_2O） is found to be the effective catalyst for cyclization reaction,giving corrole as the major product.     

Convergent synthesis of a 24-membered macrocyclic hexaoxazole derivative related to the novel telomerase inhibitor telomestatin

An efficient construction of a 24-membered macrocyclic hexaoxazole derivative pertinent to the synthesis of analogues of the important natural product telomestatin was developed, which featured a convergent union of two trisoxazole units.