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在ZINDO方法基础上,按完全态求和(SOS)公式编制了计算分子二阶非线性光学系数βijk、βμ的程序,研究了各种吩噻嗪侧环取代衍生物的结构和二阶非线性光学性质,结论是侧环上推、拉电子取代基(不太弱)对增大二阶光学非线性都有利,扩大共轭范围也对增大二阶光学非线性有利,并对上述结果在微观上给予了解释。  相似文献   

3.
以二茂铁甲醛和三羟甲氨基甲烷为原料,经缩合,脱水和还原反应合成了两种新型的二茂铁衍生物,其结构经1H NMR, IR和MS表征,并利用循环伏安法研究了它们的电化学性质.  相似文献   

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刘涛  魏用刚  袁燕秋  郭庆祥 《中国化学》2005,23(10):1430-1436
A series of N-bonded donor-acceptor derivatives of phenothiazine containing phenyl (PHPZ), anisyl (ANPZ), pyridyl (PYPZ), naphthyl (NAPZ), acetylphenyl (APPZ), and cyanophenyl (CPPZ) as an electron acceptor have been synthesized. Their photophysical properties were investigated in solvents of different polarities by absorption and emission techniques. These studies clearly revealed the existence of an intramolecular charge transfer (ICT) excited state in the latter four compounds. The solvent dependent Stokes shift values were analyzed by the modified Lippert-Mataga equation to obtain the excited state dipole moment values. The large excited state dipole moment suggests that the full (or nearly full) electron transfer take place in the A-D systems. In the system of A-D phenothiazine derivatives, the transition dipole moments Mflu were determined mainly by direct interactions between the solvent-equilibrated fluorescence ^1CT state and ground state because of their lack of significant change with increase of the solvent polarity. The electron structure and molecular conformation of phenothiazine derivatives will be significantly changed with the increase of the electron affinity of the N-10 substituent.  相似文献   

6.
从吩噻嗪出发,通过取代反应引入长链烷基,Heek反应引入乙烯基π-桥和吡啶基,合成了新化合物9-己基-3,6-二[2-(2-乙烯基吡啶)]吩噻嗪(4),其结构经1H NMR,IR和MS表征.应用UV和单光子荧光光谱初步探讨了4的光学性质.  相似文献   

7.
孙学毅  张晓峰  苏瑞飞  张伟  邓夏荷  张昭 《合成化学》2015,23(11):1033-1035
以吲哚为原料,经Vilsmeier-Haack, Ullmannhe和Witting-Hornor反应合成了两个新型的含吲哚环共轭化合物--1,4-二(3-苯乙烯基吲哚基)苯(4a)和1,4-二(3-萘乙烯基吲哚基)苯(4b),其结构经1H NMR, 13C NMR, IR和ESI-MS表征。光学性能研究结果表明,4a和4b的λmax分别位于330 nm和348 nm;在330 nm波长激发下,λem分别位于410 nm和425 nm。  相似文献   

8.
以N-乙基-3-甲酰基咔唑为原料,合成了两种新型的双咔唑基席夫碱衍生物——N1,N2-双(9-乙基咔唑-3-亚甲基)-1,2-乙二胺(1)和N1,N3-双(9-乙基咔唑-3-亚甲基)-1,3-丙二胺(2),其结构经1HNMR,IR和MS表征。用UV和单光子荧光光谱研究了1和2的线性光学性质。结果表明:1和2有望成为具有应用价值的发光材料。  相似文献   

9.
单加成环丙烷富勒烯膦酸酯衍生物的合成与电化学性能   总被引:1,自引:0,他引:1  
在Mn(OAc)3•2H2O催化下, C60分别和亚甲基二膦酸四乙酯、氰基亚甲基膦酸二乙酯或乙氧羰基亚甲基膦酸二乙酯在氯苯中回流, 生成3个单加成环丙烷富勒烯膦酸衍生物C60C(R)PO(OEt)2 [1, R=PO(OEt)2; 2, R=COOEt; 3, R=CN]. 与以前报道的Bingel反应法相比, 该方法副产物少并且缩短了反应时间. 采用循环伏安法发现1, 2的还原电位相对于C60发生负移, 而3的还原电位相对于C60却正移40 mV, 表明引入象氰基一样具有很强吸电子能力的取代基团, 可以改善富勒烯球的电化学性能, 合成电子接受能力较强的富勒烯衍生物.  相似文献   

10.
本文报道了一种新的配体:10-乙基-3-甲酰吩噻嗪缩肼基二硫代甲酸甲酯(HL)及其金属配合物的合成。采用了元素分析、质谱、核磁共振、红外光谱对配体及其金属配合物进行了表征。此外,并应用紫外、荧光和Z-扫描技术,测定了配体及其金属配合物的荧光最佳发射波长(λmaxem)、荧光量子产率(Φf)、寿命(τ)和非线性光学性质。结果表明它们在DMF溶液中都能发射出较强的橄榄色荧光,配体及其金属配合物都有双光子吸收,并且金属配合物的非线性光学效应比配体明显增强。用半经验量子化学方法(RHF/PM3)计算结果与实验值较为吻合。  相似文献   

11.
高恩君  刘蕾  朱明昌  吴琼 《中国化学》2009,27(7):1285-1290
本文报道了一个锌配合物[Zn(bipy)(pmal)(H2O)]·2H2O(其中bipy = 2,2’-联吡啶, pmal = 苯基丙二酸)的合成,晶体结构及其光谱学研究。并通过单晶X射线衍射,元素分析,红外光谱等手段对它进行了表征。同时,利用紫外光谱和荧光光谱方法考察了该配合物与小牛胸腺DNA的键和作用。琼脂糖凝胶电泳实验的结果说明该配合物的平面结构对pBR 322DNA切割作用显著。  相似文献   

12.
用紫外差光谱、红外光谱法和荧光猝灭法研究了典型多环芳烃蒽与苯甲酸及其羟基取代衍生物邻羟基苯甲酸和对羟基苯甲酸之间的作用机理。实验结果表明,在此芳香羧酸与蒽之间存在定向的、特异性的作用,其作用方式受到反应物结构和环境酸度的影响。对苯甲酸和邻羟基苯甲酸而言,当pH<pKa时,二者之间以蒽离域大π电子与羧基质子之间的π-H氢键作用为主,pH>pKa时,π-π电子给体受体作用逐渐成为主要结合方式。邻位羟基的存在使得苯甲酸与蒽的作用强度明显降低。对羟基苯甲酸特殊的D-π-A型分子结构使得它在溶液中形成平面多分子聚集体,这种多分子聚集体的生成使得对羟基苯甲酸与蒽的结合方式不随酸度变化,在pH2.0~10.0的范围内均以π-π电子给体受体作用相结合,且结合强度大于苯甲酸和邻羟基苯甲酸。  相似文献   

13.
5,10, 15-Triphenyl-20-{2- [α- (adenine-9 ) acetylamino]} phenyl porphyrin ( 1 ), 5,10, 15-triphenyl-20-{2-[α-(cytosine-1)acetylamino]} phenyl porphyrin (2), 5, 10, 15-triphenyl-20-{4-[α-(cytosine-1)ethoxy]} phenyl porphyrin (3) and their zinc complexes Zn-1, Zn-2 and Zn-3 have been prepared and characterized by ^1H NMR spectra, elemental analyses, electronic absorption spectra and mass spectra (FAB). Intramolecular π-π interactions and intramolecular metal-~ interaction for 1, 2, Zn-1,and Zn-2 have been investigated by several methods. ^1H NMR studies demonstrate that the porphyrin π-system in 1 and 2 is parallel to the adenine and the cytosine aromatic ring, respectively. The electronic absorption spectral properties of free porphyrin derivatives and their zinc complexes have been compared with those of H2TPP and ZnTPP. The results show that the UV-vis spectra of 1 and 2 are the same as that of H2TPP,whereas the spectra of their zinc complexes show 7 nm red shifts of the Soret bands compared to that of ZnTPP. The emission spectra of Zn-1 and Zn-2 are independent of excitation wavelength. From combination of the evidence of absorption and emission spectra it is suggested the existence of intramolecular metal-π interaction in Zn-1 and Zn-2. The results of conformational analysis agreed quite nicely with that of experiments, thus it was further to validate the experimental conclusions.  相似文献   

14.
A series of rod‐shaped and related three‐branched push–pull derivatives containing phosphane oxide or phosphane sulfide (PO or PS)—as an electron‐withdrawing group conjugated to electron‐donating groups, such as amino or ether groups, with a conjugated rod consisting of arylene–vinylene or arylene–ethynylene building blocks—were prepared. These compounds were efficiently synthesized by a Grignard reaction followed by Sonogashira coupling. Their photophysical properties including absorption, emission, time‐resolved fluorescence, and two‐photon absorption (TPA) were investigated with special attention to structure–property relationships. These fluorophores show high fluorescence quantum yields and solvent‐dependent experiments reveal that efficient intramolecular charge transfer occurs upon excitation, thereby leading to highly polar excited states, the polarity of which can be significantly enhanced by playing on the end groups and conjugated linker. Rod‐shaped and related three‐branched systems show similar fluorescence properties in agreement with excitation localization on one of the push–pull branches. By using stronger electron donors or replacing the arylene–ethynylene linkers with an arylene–vinylene one induces significant redshifts of both the low‐energy one‐photon absorption and TPA bands. Interestingly, a major enhancement in TPA responses is observed, whereas OPA intensities are only weakly affected. Similarly, phosphane oxide derivatives show similar OPA responses than the corresponding sulfides but their TPA responses are significantly larger. Finally, the electronic coupling between dipolar branches promoted by common PO or PS acceptor moieties induces either slight enhancement of the TPA responses or broadening of the TPA band in the near infrared (NIR) region. Such behavior markedly contrasts with triphenylamine‐core‐mediated coupling, which gives evidence for the different types of interactions between branches.  相似文献   

15.
将两种具有相似手性联萘空腔的手性卟啉1b和2b作为催化剂,对苯乙烯衍生物及非芳香烯烃底物进行了催化不对称环氧化反应。应用理论计算方法研究了底物同两种催化剂之间的作用机理;应用1H NMR探讨了催化剂的手性空腔结构;结果表明芳香烯烃同催化剂的手性联萘基团之间的p-p相互作用是决定该类催化剂对映选择性的重要因素,同时催化剂手性结构的立体位阻效应使该类催化剂具有良好的ee值。  相似文献   

16.
Two new trinuclear complexes [CuII(NiIIX1)2(C2H5OH)2]· (ClO4)2·2(CH3OH) ( 1 ) and [CuII(NiIIX2)2(H2O)]·(ClO4)2· 0.75(H2O) ( 2 ) (X1 = dianion of 5,6;13,14‐dibenzo‐7,12‐bis(ethoxycarboxyl)‐9‐methyl‐2,3‐dioxo‐1,4,8,11‐tetraazacyclotetradeca‐7,11‐diene. X2 = dianion of 5,6;13,14‐dibenzo‐9,10‐cyclohexano‐7,12‐bis(ethoxycarboxyl)‐2,3‐dioxo‐1,4,8,11‐tetraazacyclotetradeca7,11‐diene.) have been synthesized and characterized by single crystal X‐ray analysis, elemental analysis, IR, UV and EPR spectroscopies. The complexes consist of NiIICuIINiII heteronuclear cationic entities. The central CuII atom of 1 lies in an octahedral coordination environment, while that of 2 resides in a square‐pyramidal coordination sphere. The adjacent trinuclear units of 1 are linked together through π‐π stacking interactions resulting in a 1D supramolecular chain, whereas the π‐π stacking interactions between the contiguous units of 2 lead to a 2D structure. The EPR spectra of the two complexes show a signal of an axially elongated octahedral CuII system in 1 and an axially elongated square‐pyramidal CuII system in 2 , respectively. The hyperfine splitting of the CuII atoms (ICu = 3/2) has also been observed in the EPR spectra.  相似文献   

17.
A series of terrylene derivatives, such as monoazaterrylene (MATerry), 1,6‐diazaterrylene (DiATerry) and pristine terrylene (Terry), were synthesized by changing the number of nitrogen atoms at the bay region (1 and 6 positions of the Terry core). The electrochemical measurements suggested that the first one‐electron reduction and oxidation potentials became positively shifted with increasing numbers of nitrogen atoms. This agreed with the energies of the corresponding highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) states estimated by DFT methods. In contrast, the HOMO–LUMO gaps approximately remained constant. This trend is quite similar to the spectroscopic behaviors observed by absorption and fluorescence spectra. The solvent polarity‐dependent spectroscopic trends of DiATerry suggested the intramolecular charge‐transfer (ICT) characters. The evaluation of the excited‐state dynamics in various solvents indicated the electronic configurational changes of the excited states relative to the ground state via the ICT. This was supported by the Lippert–Mataga plots. Finally, the reversible protonation and deprotonation processes were also observed.  相似文献   

18.
邓秀琴  葛春华 《合成化学》2015,23(2):134-136
以二茂铁甲酸为原料,经氯代和酰胺化反应合成了两个新型的二茂铁甲酰胺衍生物——N-苯基二茂铁甲酰胺(4a)和N-4-甲苯基二茂铁甲酰胺(4b),其结构经1H NMR,IR和MS表征。利用循环伏安法研究了4a和4b的电化学性质。结果表明,扫描速率为10 m V·s-1时,4a和4b分别在1.2 V~-0.05 V和0.8 V~-0.4 V出现一对氧化还原峰,ΔEp分别为0.09 V和0.05 V,ipc/ipa≈1。  相似文献   

19.
A new compound 1,1‘-bis(3-pyridyl)-propylene(3,7-diformyl-N-ethylphenothiazinyl)ketone (C30H23N3O2S, Mr = 489.4) has been synthesized, and its crystal structure was determined by single-crystal X-ray diffraction method. The crystal is of orthorhombic, space group Ima2 with a = 27.491 (5), b = 11.942(2), c = 7.389(2) A, V = 2425.8(7) A^3, Z = 8, Dc =1.340 g/cm^3,μ = 0,167 mm ^1, F(000) = 1024, the final R = 0.0363 and wR = 0.0869 for 2054 unique reflections with Rint = 0.0254. The structural determination shows that the molecule assumes a butterfly configuration with nearly planar wings. In addition, the electrochemical study indicates that there is a high electronic delocalization in the molecule.  相似文献   

20.
The title polymeric complex [Cu(C4H2O4)(C10H8N2)]n·2nH2O was prepared and its crystal structure was determined by X‐ray diffraction methods. The crystal belongs to space group P21/c with cell dimensions of a = 1.0104(1), b = 1.9952(2), c = 0.7357(2) nm, β= 98.38(2)° and Z = 4. The complex forms zig‐zag chains along crystallographic axis c via Cu—O (carboxyl) bond in the apical direction. Each repeated unit consists of a square pyramidal Cu(II) centre with one maleate dianion and one 2,2′‐bipyridine forming a basal plane. Adjacent chains link to each other by H‐bonding between carboxyl groups and crystalline water. The distance of 0.3482 nm between parallel bipyridine rings shows a π‐π stacking interaction. The title complex was also characterized by IR, UV and ESR spectra.  相似文献   

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