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1.
设计合成了一系列新型的meso位N,N-二甲氨基苯基或N-苯基咔唑基单取代卟啉(5a~c)及其锌配合物(6a~c),用高分辨质谱、~1H NMR、紫外-可见光谱及X射线单晶衍射方法等对结构进行了表征;研究了卟啉化合物及其配合物的热稳定性及荧光性质。结果表明,这些卟啉化合物及其锌配合物在400~410 nm之间具有强的吸收且具有很好的热稳定性,荧光量子产率在0.05~0.09;另外还分析了meso位不同取代基对光谱性质的影响。  相似文献   

2.
将硝基修饰于四苯基卟啉meso位苯环的邻、间、对位上,合成了三个化合物o-TNPP、m-TNPP及p-TNPP。考察了不同取代位点的硝基对卟吩环上电子云密度分布的影响。通过溶剂化效应、AIE效应、pH效应、循环伏安曲线测试表明,o-TNPP、p-TNPP的卟吩环内电子云密度减小,共轭增强,表现出ACQ性质。m-TNPP的meso位苯环上电子云呈螺旋桨式分布于硝基外围,使卟啉发生空间扭曲,共轭削弱,表现出AIE性质。  相似文献   

3.
设计合成了一系列新型的mesoN,N-二甲氨基苯基或N-苯基咔唑基单取代卟啉(5a~c)及其锌配合物(6a~c),用高分辨质谱、1H NMR、紫外-可见光谱及X射线单晶衍射方法等对结构进行了表征;研究了卟啉化合物及其配合物的热稳定性及荧光性质。结果表明,这些卟啉化合物及其锌配合物在400~410 nm之间具有强的吸收且具有很好的热稳定性,荧光量子产率在0.05~0.09;另外还分析了meso位不同取代基对光谱性质的影响。  相似文献   

4.
设计合成了一系列新型的mesoN,N-二甲氨基苯基或N-苯基咔唑基单取代卟啉(5a~c)及其锌配合物(6a~c),用高分辨质谱、1H NMR、紫外-可见光谱及X射线单晶衍射方法等对结构进行了表征;研究了卟啉化合物及其配合物的热稳定性及荧光性质。结果表明,这些卟啉化合物及其锌配合物在400~410 nm之间具有强的吸收且具有很好的热稳定性,荧光量子产率在0.05~0.09;另外还分析了meso位不同取代基对光谱性质的影响。  相似文献   

5.
稀土卟啉络合物可用做特殊的核磁共振位移试剂和生物大分子的探针。有关这类络合物已有许多研究,但几乎全部都是中位(meso位)对称苯基或对称取代苯基卟啉的稀土络合物,本文报告一种不对称苯基取代卟啉稀土络合物即乙酰丙酮-5-对羟基苯基-10,15,  相似文献   

6.
锌卟啉的合成及与咪唑类客体反应的光谱性质   总被引:1,自引:0,他引:1  
将一对手性丙氨酸,通过烷氧基侧链与卟啉环相连,合成了一对手性卟啉5-对(L-丙氨酰氧乙氧基)苯基-10,15,20-三苯基卟啉和5-对(D-丙氨酰氧乙氧基)苯基-10,15,20-三苯基卟啉及其各自对应的锌卟啉.通过元素分析、紫外-可见光谱、1 H核磁共振和红外光谱等方法对合成的自由卟啉及锌卟啉配合物进行了结构确定.此外,采用荧光光谱滴定实验研究了金属锌卟啉与咪唑类客体进行配位反应的光谱性质,结果表明,咪唑类客体与手性锌卟啉相互作用时均具有荧光猝灭效应,金属卟啉的手性结构对该性质未造成影响.  相似文献   

7.
哌嗪取代卟啉的合成、表征及其抗癌活性   总被引:2,自引:0,他引:2  
李和平  郭灿城  阮建明  黄伯云 《有机化学》2004,24(7):783-787,J003
设计并合成了6个具有抗癌活性的哌嗪取代卟啉化合物,分别为5,10,15,20-四[4-(4'-乙基哌嗪基)苯基]卟啉(TEPPH2,8a),5,10,15,20-四[4-(4'-丁基哌嗪基)苯基]卟啉(TBPPH2,8b),5,10,15,20-四[4-(4'-庚基哌嗪基)苯基]卟啉(THPPH2,8c),5,10,15,20-四[4-(4'-苯基哌嗪基)苯基]卟啉(TPhPPH2,8d),5-[4-(4'-乙基哌嗪基)苯基]-10,15,20-三苯基卟啉(EPTPPH2,8e)和5-[4-(4'-丁基哌嗪基)苯基]-10,15,20-三苯基卟啉(BPTPPH2,8f).这些卟啉化合物都由取代苯甲醛与吡咯缩合而成,每一个卟啉分子中含有一个或四个具有抗癌活性的取代哌嗪结构,结构经元素分析,MS,1H NMR,IR和UV-vis等表征.初步的生物活性研究表明,这些化合物具有一定的抗癌活性,因而在医学上可能具有潜在应用前景.  相似文献   

8.
采用Adler法合成了Meso-四(对羟基苯基)卟啉(THPP), 在均相体系中使聚甲基丙烯酸缩水甘油酯(PGMA)与THPP发生开环反应, 得到侧链键合有羟基苯基卟啉的线型PGMA(HPP-PGMA); 进一步使HPP-PGMA与锰离子发生配合作用, 得到侧链键合有锰卟啉(MnP)的线型PGMA(MnP-PGMA), 测定了HPP-PGMA的1H NMR谱, 表征了其化学结构; 测定了HPP-PGMA与MnP-PGMA的UV-Vis光谱及荧光发射光谱, 考察了其光物理行为. 实验结果表明, 通过THPP外环上羟基与PGMA侧基环氧键的开环成醚反应, 可以顺利地将羟基苯基卟啉及其锰配合物键合在PGMA的侧链上. HPP-PGMA具有THPP的特征电子吸收光谱与荧光发射光谱, 且随着THPP键合度的增加, 光谱的强度增强. MnP-PGMA具有小分子锰卟啉的特征电子吸收光谱与荧光特征, 其Soret吸收带发生显著红移(红移58 nm), Q吸收带的数量减为3个吸收峰; 实验发现, MnP-PGMA与小分子锰卟啉类似, 在Q发射带没有荧光发射.  相似文献   

9.
设计合成了具有不同外围取代基的卟啉铂(Ⅱ)配合物PtTEMP,PtTBMP,PtOMPP和PtDMPP,并对其结构和光电性能进行了表征.晶体结构分析结果表明,这些卟啉铂(Ⅱ)配合物具有较理想的平面配位构型,β-位叔丁基的引入有效抑制了分子间的π-π相互作用.外围取代基几乎不影响配合物的吸收和发光性质,最大发射峰位于646~656 nm之间,为配体中心的3π*-π磷光发射.空间位阻效应更强的叔丁基取代配合物(PtTBMP)的溶液态荧光量子效率和外量子效率最高,分别为0.58和6.3%.3个甲氧基取代的PtDMPP的发光效率优于2个甲氧基取代的PtOMPP,二者的溶液态荧光量子效率分别为0.36和0.29,外量子效率分别为2.4%和1.7%.  相似文献   

10.
通过密度泛函理论计算比较性地研究了5,15-二(4-(5-乙酰基硫戊氧基)苯基)自由卟啉及其锌配合物的分子结构、电荷性质、分子轨道、电子吸收光谱和红外光谱.这类化合物具有在卟啉相对的两个中位的苯环上连有5-乙酰基硫戊氧基的新颖结构.模拟得到的这两个化合物的分子结构和电子吸收光谱以及红外光谱都与实验测得的符合得很好.通过与未取代的自由卟啉和卟啉锌的结构和性质进行比较,研究了中位取代基、极性溶剂和中心金属取代对此类卟啉化合物结构和性质的影响规律.对化合物的电子吸收光谱中的电子跃迁本质进行了归属,并通过基于正则坐标分析产生的动画对红外光谱的振动模式进行了指认.目前的工作将对理解此类新颖卟啉化合物的结构和性质以及取代基和溶剂效应提供很大的帮助.  相似文献   

11.
Two synthetic methods of meso-aryl-substituted subporphyrins have been developed by means of the reaction of pyridine-tri-N-pyrrolylborane with a series of aryl aldehydes. One method relies on the condensation under Adler conditions with chloroacetic acid in refluxing 1,2-dichlorobenzene to afford subporphyrins in 1.1-3.2%, and the other is a two-step reaction consisting of the initial treatment of the two substrates with trifluoroacetic acid at 0 degrees C followed by air-oxidation in refluxing 1,2-dichlorobenzene to provide subporphyrins in up to 5.6% yield. 1H NMR studies indicate that phenyl and sterically unhindered substituents at the meso position of subporphyrins rotate rather freely even at -90 degrees C, whereas the rotation of meso-2,4,6-trimethoxyphenyl substituents is strictly prohibited even at 130 degrees C. The structures of six subporphyins have been revealed by X-ray crystallographic analysis to be all cone-shaped tripyrrolic macrocycles. Dihedral angles of meso-phenyl and sterically unhindered aryl substituents to the subporphyrinic core are rather small (38.3-55.7 degrees ) compared to those of porphyrin analogues, whereas those of meso-2,4,6-trimethoxy-substituted subporphyrins are large (68.7-75.7 degrees ). These rotational features of the meso-aryl substituents lead to their large influences on the electronic properties of subporphyrins, as seen for 4-nitrophenyl-substituted subporphyrin 14e that exhibits perturbed absorption and fluorescence spectra, depending upon solvents. Large solvent-polarity dependence of the fluorescence of 14e suggests the charge-transfer character for its excited state. Electrochemical and theoretical studies are performed to understand the electronic properties. Overall, meso-aryl-substituted subporphyrins are promising chromophores in future functional devices.  相似文献   

12.
Despite significant interest, the chiroptical properties of subporphyrins have rarely been investigated because chiral subporphyrins are elusive. Here, inherently chiral subporphyrins are elaborated by forming a fused pyran ring at the periphery of an A2B-type meso-aryl-substituted subporphyrin. Their circular dichroism (CD) properties are largely affected by the peripheral substituents and the dihedral angles between the meso-aryl substituents and the subporphyrin core: the β-perbromo subporphyrin with an orthogonal arrangement of the meso-phenyl substituents to the subporphyrin core exhibits weak CD signals corresponding to the Q bands, whereas the unsubstituted species with smaller dihedral angles shows relatively intense CD signals. A detailed structure–property relationship of these chiral subporphyrins was elucidated by time-dependent (TD) DFT calculations. This study reveals that the CD properties of chiral subporphyrins can be controlled by peripheral substitution and meso-aryl substituents.  相似文献   

13.
Boron arylations of B‐(methoxo)triphenylsubporphyrin have been developed with a combined use of ArZnI?LiCl and trimethylsilyl chloride. Aryl zinc reagents bearing bromo, cyano, amide, and ester groups can be employed for the B‐arylation reaction to provide the corresponding B‐arylated subporphyrins in moderate yields. Postmodifications of B‐arylated subporphyrins have been demonstrated without loss of the B?C bond. These modifications include conversion of the cyano group into a benzoyl group with PhMgBr, hydrolysis of the ester group to give B‐(4‐carboxyphenyl)subporphyrin, and Pd‐catalyzed Suzuki–Miyaura coupling of the 4‐bromophenyl group to give a 1,4‐phenylene‐bridged subporphyrin–ZnII porphyrin hybrid that displays intramolecular excitation energy transfer from the subporphyrin to the porphyrin. The newly synthesized B‐arylated subporphyrins have been fully characterized by NMR, UV/Vis absorption and fluorescence spectroscopies, mass spectrometry, electrochemical measurements, and X‐ray diffraction analysis.  相似文献   

14.
B-Phenyl BIII subporphyrin-α-diones prepared in a three-step reaction sequence from the parent subporphyrin were condensed with 1,2-diaminobenzenes to give the corresponding quinoxaline-fused subporphyrins in variable yields. Quinoxaline-fused B-phenyl-5,10,15-triphenyl BIII subporphyrin was transformed to the corresponding subporphyrin-α-dione in the same three-step reaction sequence, which was then condensed with 1,2-diaminobenzene to give doubly quinoxaline-fused subporphyrin. These quinoxaline-fused subporphyrins exhibit redshifted absorption and fluorescence spectra compared with the parent one. A singly quinoxaline-fused subporphyrin bearing three meso-bis(4-dimethylaminophenyl)aminophenyl substituents shows blueshifted fluorescence in less polar solvent, which has been ascribed to emission associated with charge recombination of intramolecular charge transfer (CT) state.  相似文献   

15.
Iridium‐catalyzed borylation of B‐aryl meso‐free subporphyrinato boron(III) complexes (hereinafter referred to simply as subporphyrins) with bis(pinacolato)diboron gave 2,13‐diborylated subporphyrins regioselectively, which served as promising synthetic precursors for 2,13‐diarylated subporphyrins and doubly β‐to‐β 1,3‐butadiyne‐bridged subporphyrin dimers. 2,13‐Diarylated subporphyrins display perturbed absorption spectra, depending upon the β‐aryl substituents. Doubly 1,3‐butadiyne‐bridged syn and anti subporphyrin dimers thus prepared exhibit differently altered absorption spectra with split Soret‐like bands, which have been accounted for in terms of exciton coupling.  相似文献   

16.
Effective peripheral fabrication methods of meso‐aryl‐substituted subporphyrins were explored for the first time. Hexabrominated subporphyrins 2 were prepared quantitatively from the bromination of subporphyrins 1 with bromine. Hexaphenylated subporphyrins 3 and hexaethynylated subporphyrins 4 and 5 were synthesized by Suzuki–Miyaura coupling and Stille coupling, respectively, in good yields. X‐ray crystal structures of 2 b , 3 b , 4 b , and 5 a revealed preservation of the bowl‐shaped bent structures with bowl depths similar to that of 1 . Hexaethynylated subporphyrins exhibit large two‐photon‐absorption cross‐sections due to effective delocalization of the conjugated network to the ethynyl substituents.  相似文献   

17.
meso‐Free BIII 5,10‐bis(p‐dimethylaminophenyl)subporphyrins were synthesized. They display red‐shifted absorption and fluorescence spectra, bathochromic behaviors in polar solvents, a high fluorescence quantum yield (ΦF=0.57), and a small HOMO–LUMO gap mainly due to destabilized HOMO as compared with meso‐free BIII 5,10‐diphenylsubporphyrin. This subporphyrin serves as a nice precursor of various meso‐substituted BIII subporphyrins such as BIII meso‐nitrosubporphyrin, BIII meso‐aminosubporphyrin, and meso‐meso’ linked BIII azosubporphyrin dimer. Reactions of meso‐free BIII subporphyrins with NBS or bis(2,4,6‐trimethylpyridine)bromonium hexafluorophosphate gave meso‐meso′ linked subporphyrin dimers, often as a major product along with meso‐bromosubporphyrins.  相似文献   

18.
Subbacteriochlorins, which were prepared via hydrogenation of subporphyrins with Raney nickel, are modestly aromatic due to 14π-diazaannulenic circuit and exhibit characteristic blue-shifted Soret-like bands, intensified fluorescence spectra, and high oxidation potentials.  相似文献   

19.
A2B‐type B‐methoxy subporphyrins 3 a – g and B‐phenyl subporphyrins 7 a – c , e , g bearing meso‐(2‐substituted)aryl substituents are synthesized, and their rotational dynamics are examined through variable‐temperature (VT) 1H NMR spectroscopy. In these subporphyrins, the rotation of meso‐aryl substituents is hindered by a rationally installed 2‐substituent. The rotational barriers determined are considerably smaller than those reported previously for porphyrins. Comparison of the rotation activation parameters reveals a variable contribution of ΔH and ΔS in ΔG. 2‐Methyl and 2‐ethyl groups of the meso‐aryl substituents in subporphyrins 3 e , 3 f , and 7 e induce larger rotational barriers than 2‐alkoxyl substituents. The rotational barriers of 3 g and 7 g are reduced by the presence of the 4‐dibenzylamino group owing to its ability to stabilize the coplanar rotation transition state electronically. The smaller rotational barriers found for B‐phenyl subporphyrins than for B‐methoxy subporphyrins indicate a negligible contribution of SN1‐type heterolysis in the rotation of meso‐aryl substituents.  相似文献   

20.
Donor–acceptor systems based on subporphyrins with nitro and amino substituents at meta and para positions of the meso‐phenyl groups were synthesized and their photophysical properties have been systematically investigated. These molecules show two types of charge‐transfer interactions, that is, from center to periphery and periphery to center depending on the peripheral substitution, in which the subporphyrin moiety plays a dual role as both donor and acceptor. Based on the solvent‐polarity‐dependent photophysical properties, we have shown that the fluorescence emission of para isomers originates from the solvatochromic, dipolar, symmetry‐broken, and relaxed excited states, whereas the non‐solvatochromic fluorescence of meta isomers is of the octupolar type with false symmetry breaking. The restricted meso‐(4‐aminophenyl) rotation at low temperature prevents the intramolecular charge‐transfer (ICT)‐forming process. The two‐photon absorption (TPA) cross‐section values were determined by photoexcitation at 800 nm in nonpolar toluene and polar acetonitrile solvents to see the effect of ICT on the TPA processes. The large enhancement in the TPA cross‐section value of approximately 3200 GM (1 GM=10?50 cm4 s photon?1) with donor–acceptor substitution has been attributed to the octupolar effect and ICT interactions. A correlation was found between the electron‐donating/‐withdrawing abilities of the peripheral groups and the TPA cross‐section values, that is, p‐aminophenyl>m‐aminophenyl>nitrophenyl. The increased stability of octupolar ICT interactions in highly polar solvents enhances the TPA cross‐section value by a factor of approximately 2 and 4, respectively, for p‐amino‐ and m‐nitrophenyl‐substituted subporphyrins. On the other hand, the stabilization of the symmetry‐broken, dipolar ICT state gives rise to a negligible impact on the TPA processes.  相似文献   

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