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121.
以羧酸配体 2,2''-(1,4-亚苯基双(亚苯基))双(硫二基)二苯甲酸(H2L1)和 2,2''-(2,3,5,6-四甲基-1,4-亚苯基)双(亚甲基)双(硫二基)二苯甲酸(H2L2)分别与金属盐反应,通过溶剂热方法合成了 3个配位聚合物:{[Ni(L1)(H2O)4]·2H2O}n (1)、[Zn(L1)(DMA)2]n(2)和[Co(L2)(DMF)2]n (3),其中DMA=N,N-二甲基乙酰胺,DMF=N,N-二甲基甲酰胺。对配合物1~3进行了单晶X射线衍射、元素分析、红外光谱、热重分析、粉末X射线衍射和固体紫外可见光谱测试和表征。单晶X射线衍射表明:3个配合物均为一维锯齿形链状结构,并通过氢键作用形成三维骨架,且配体均表现为反式构象。此外,对配合物2固态荧光性质进行了研究。  相似文献   
122.
Three coordination compounds with dimensions from 0D to 2D, namely, [Co(bppdca)2(HL1)2] ( 1 ) [Co(bppdca)(L2)(H2O)] · 2H2O ( 2 ) and [Co(bppdca)(L3)] · 3H2O ( 3 ) [bppdca = N,N′‐bis(pyridine‐3‐yl)pyridine‐2,6‐dicarboxamide, H2L1 = 2,5‐pyridinedicarboxylic acid, H2L2 = 4,4′‐oxybisbenzoic acid, H2L3 = 2‐carboxymethylsulfanyl nicotinic acid] were hydrothermally synthesized and structurally characterized. Single crystal X‐ray diffraction analysis reveals that complex 1 is a discrete 0D complex, in which the bppdca ligand and the H2L1 act as the terminal groups to coordinate with the CoII ions. In coordination polymer 2 , two bppdca ligands coordinate in anti configuration with two CoII ions to generate a 28‐membered Co2(bppdca)2 loop, which is further extended into 1D ladder‐like double chain by pairs of L2 ligands. In 3 , the CoII ions are linked by bppdca ligands to generate 1D wave‐like chain, which is further connected by the L3 to form a 2D network. Finally, the coordination compounds 1 – 3 are extended into 3D supramolecular frameworks through the hydrogen bonding interactions. The CoII ions and the bppdca ligands in the title coordination compounds exhibit different coordination characters and conformations. The effect of organic dicarboxylates with different rigidity and length on the structures of CoII coordination compounds was investigated. In addition, the fluorescence and electrochemical behaviors of coordination compounds 1 – 3 were reported.  相似文献   
123.
氧化双[三(2-甲基-2-苯基)丙基]锡分别与酒石酸、乙二酸反应,合成了2个二[三(2-甲基-2-苯基)丙基锡]二元羧酸酯[CH(OH)COOSn(CH2Me2CPh)3]2(1)和[COOSn(CH2Me2CPh)3]2·2Me OH(2)。经元素分析、IR、1H和13C-NMR以及X-射线单晶衍射表征结构。化合物中,锡原子均为畸变四面体构型,分子间通过O-H…O和C-H…O氢键作用,化合物1和2分别形成一维无限链结构和二维网状结构。在空气氛下化合物有较好的热稳定性;除草活性结果表明,化合物1和2对马齿苋、稗草、反枝苋、决明子、狗尾草和藜等农作物杂草显示出一定的生物活性,特别是对马齿苋、狗尾草和藜的茎和根的作用较明显,化合物2在25 mg·L-1的较低浓度下选择性、高效地抑制马齿苋的茎和根的生长,为马齿苋的除草剂研究提供了一种方法。  相似文献   
124.
In order to improve the thermal and mechanical properties of the poly(butylene 1,12-dodecanedioate), some novel aliphatic-aromatic random copolyesters have been prepared by starting from 1,4-butanediol and different molar ratio of 1,12-dodecanedioc acid and terephthalic acid. The samples were characterized by 1H NMR and the molecular structure was correlated with the crystalline phase present, the level of crystallinity, the glass transition temperature, the mechanical behavior, and the biodegradability. In particular, the copolymer containing the 70 mol% of PBT repeating units notably improves the thermal and mechanical properties of the poly(butylene 1,12-dodecanedioate) towards those of PBT and maintains a very high thermal stability, but loses the biodegradability of the poly(alkylene dicarboxylate). Therefore, for this class of aliphatic-aromatic copolymers the chemical composition must be carefully chosen to reach a compromise between good thermal and mechanical performances and biodegradability, according to the necessity.  相似文献   
125.
Three lanthanide–organic polymers, {[Ln(μ 3-HPhIDC)(μ 2-C2O4)0.5(H2O)]?·?2H2O} n (Ln?=?Nd (1), Sm (2), and Tb (3)), have been isolated from the reaction of 2-phenyl-1H-imidazole-4,5-dicarboxylic acid (H3PhIDC) with equal amount of Ln(III) salts under solvothermal condition with the rigid coligand oxalate. The three polymers, which are isomorphous and isostructural, have been structurally characterized by elemental analyses, IR spectroscopy, and single-crystal X-ray diffraction. Each exhibits a 3-D framework constructed from infinite 2-D layers joined by μ 2-C2O4, which are composed of μ 3-HPhIDC2? and trivalent lanthanide. Thermal properties have also been investigated.  相似文献   
126.
Five lanthanide(III) coordination polymers with 2-methyl-1H-imidazole-4,5-dicarboxylic acid (H3MIDC) and ammonium oxalate, {[(Ln1)2(HMIDC)2(C2O4)(H2O)3]?·?3H2O} n (Ln1?=?Nd (1), Sm (2)), {[Eu2(HMIDC)2(C2O4)(H2O)3]?·?0.5EtOH?·?3H2O} n (3), {[Ce2(HMIDC)2(C2O4)(H2O)3]?·?EtOH?·?3H2O} n (4), and {[Gd2(HMIDC)2(C2O4)(H2O)3]?·?MeOH?·?3H2O} n (5), have been prepared and structurally characterized. Single-crystal X-ray diffraction analyses reveal that 1 and 2 are isostructural, as are 3, 4, and 5. Each exhibits a 3-D open framework, which is built by a regular 2-D grid connected by HMIDC2? and Ln(III). The luminescence and thermal properties of these complexes have been investigated as well.  相似文献   
127.
Two polymeric frameworks, [Zn5(MIDC)2(HMIDC)2(phen)5] n (1) (H3MIDC?=?2-methyl-1H-imidazole-4,5-dicarboxylic acid, phen?=?1,10-phenanthroline) and {[Ca2(HEIDC)2(H2O)]?·?H2O} n (2) (H3EIDC?=?2-ethyl-1H-imidazole-4,5-dicarboxylic acid), have been solvothermally synthesized and structurally characterized by single-crystal X-ray diffraction. Compound 1 exhibits a 3-D structure constructed from 2-D layer motifs joined by µ 2-HMIDC2? or µ 3-MIDC3? ligands. Compound 2 also presents a 3-D framework, generated from 1-D chains linked by HEIDC2? ligands by two different µ5-modes. The thermal and solid-state photoluminescence properties of both the complexes have been determined.  相似文献   
128.
2,6-萘二甲酸二甲酯与一些二甲基萘可以形成激基复合物。本文通过稳态和动态荧光光谱研究了这类激基复合物的形成与分子结构的关系。结果表明,尽管这些二甲基萘的电离能基本相同,但因取代基位置不同使分子中电荷分布不同,从而影响了激基复合物的形成能力。  相似文献   
129.
1INTRODUCTIONThestudiesoforganotincompoundsareofcurentinterestowingtotheirwiderangeofapplications〔14〕suchasbiocidesandhomogen...  相似文献   
130.
Information on the crystalline structure and the properties of poly(butylene‐2,6‐naphthalene dicarboxylate) (PBN) has not been well reported until now, but it is known that there are two different crystal modifications in PBN, as follows: one is formed in isotropic samples by annealing (α form); another appears by annealing with tension (β form). The relation between the crystal modifications and the kinetics of isothermal crystallization for PBN was investigated using in‐situ Fourier transform infrared spectroscopy (FTIR) and wide‐angle X‐ray diffraction (WAXD). The melting behavior of each crystalline form was also studied by means of FTIR and differential scanning calorimetry (DSC) measurements. From the analysis of the melt‐crystallized PBN specimens, the two crystalline forms coexisted in the isotropic samples melt‐crystallized at 230°C, but only the α crystal modification was observed in the films annealed at lower temperatures. In addition, it was revealed that, at 230°C, the β modification was formed only in the primary crystallization process. © 1999 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 37: 561–574, 1999  相似文献   
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