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1.
通过席夫碱配体N-(2-吡咯甲基)-1-苯基乙亚胺与三乙基铝按物质的量之比为1:1在无氧无水的条件下反应,合成了席夫碱铝的有机金属化合物N-(2-吡咯甲基)-1-苯基乙亚胺·二甲基铝。其结构分别用核磁氢谱、碳谱,元素分析和X射线单晶衍射技术进行了表征。铝化合物在催化外消旋丙交酯开环聚合反应中表现出了中等的活性并得到了以等规聚合为主的高聚物。  相似文献   

2.
聚丙交酯(PLA)可以生物降解,产物无毒,可用于外科手术的缝合线、人造器官以及药物缓释等方面,因此引起了人们的广泛注意.丙交酯的开环聚合是合成聚丙交酯的一种方便方法,所用的催化剂主要是主族及副族金属的配合物,如双金属氧桥配合物[‘j,烷基金属有机化合物[‘j,异丙氧基铝[’‘以及叶琳铝「“等.最近,关于三价烷氧基稀土化合物作为单组份催化剂催化丙交酯开环聚会已有报道[’·’‘.我们发现两价芳氧基稀土化合物(ArO)。Sin(THF)。(ArO一2,已二叔丁基一个甲基苯氧基)也可以有效地催化丙文酯的开环聚合.本…  相似文献   

3.
4.
本文合成了吡咯修饰的二茂稀土金属有机化合物,并研究了该化合物对丙交酯的聚合,结果显示该化合物可以在很宽的温度范围内实现对丙交酯的高转化率聚合.  相似文献   

5.
单脒基铝络合物催化己内醋聚合及己内醋/丙交醋共聚   总被引:1,自引:0,他引:1  
钱峰  刘克印  马海燕 《催化学报》2011,32(1):189-196
将单脒基铝络合物用于催化6-己内酯(e-CL)开环聚合反应,结果表明,该类铝络合物表现出很高的催化活性:25℃时络合物({PhC(N-2,6-iPr2C6H3)2)A1Me2](Cl)催化ε-CL聚合1h,单体转化率为91%;70℃时络合物[{PhC(N-2,6-iPr2C6H3)-(N-2,6-Me2C6H3)}Al...  相似文献   

6.
摘要以非手性的席夫碱-异丙氧基铝(Ⅱ)引发外消旋丙交酯(rac-LA)的立构选择性聚合. 其聚合动力学研究结果表明, 聚合反应对于单体符合一级反应动力学. 所得聚合物的数均分子量与单体转化率成正比, 并且分子量分布很窄, 表明该聚合反应具有良好的可控性. 此外所得的聚外消旋乳酸是tm为179 ℃的结晶性聚合物. 13C NMR和同核去偶1H NMR谱表明, 所得的聚乳酸是一种立构嵌段聚合物, 平均嵌段长度为11个乳酸单元.  相似文献   

7.
设计、 合成了一系列不对称席夫碱配体, 得到了相应的金属铝配合物. 研究了配合物在外消旋丙交酯的开环聚合反应中的催化性能. 结果表明, 系列配合物对外消旋丙交酯(rac-LA)的聚合催化活性明显提高, 并具有立体选择性.  相似文献   

8.
通过席夫碱配体N-(2-吡咯甲基)-1-苯基乙亚胺与三乙基铝按物质的量之比为1∶1在无氧无水的条件下反应,合成了席夫碱铝的有机金属化合物N-(2-吡咯甲基)-1-苯基乙亚胺·二甲基铝。其结构分别用核磁氢谱、碳谱,元素分析和X射线单晶衍射技术进行了表征。铝化合物在催化外消旋丙交酯开环聚合反应中表现出了中等的活性并得到了以等规聚合为主的高聚物。  相似文献   

9.
肌酐乳酸胍催化L-丙交酯活性开环聚合反应研究   总被引:1,自引:0,他引:1  
合成了一种新型有机胍化合物即肌酐乳酸胍(CGLA),并将其应用于L-丙交酯(LLA)的开环聚合反应.聚合反应动力学研究表明,CGLA引发的LLA开环聚合反应具有典型活性聚合反应特征,ln[M]0/[M]t-t、Mn-Conversion关系均呈准直线关系.同核去偶1H-NMR法对产物立构规整度的表征证明所合成PLLA具有较高等规度(76%).聚合反应的添加剂效应研究证明了大分子活性物种的非自由基及非离子性本质.以1H-NMR法对聚合反应的跟踪和增长大分子物种结构的表征证明了增长大分子活性端为肌酐胍-烷氧结构(CG-OR),在实验研究的基础上推断CGLA引发的丙交酯开环聚合反应遵循配位插入增长机理.  相似文献   

10.
乙酰丙酮铁催化丙交酯开环聚合的研究   总被引:7,自引:0,他引:7  
以乙酰丙酮铁 [Fe(acac) 3]为催化剂进行D ,L 丙交酯的开环聚合及在聚乙二醇 (PEG)存在下的开环共聚 ,研究了催化剂用量、反应温度和反应时间对聚合反应的影响以及PEG用量对共聚反应的影响 ,并探讨了丙交酯开环聚合机理 .结果表明 ,Fe(acac) 3是按配位 插入机理催化丙交酯开环聚合的 ;在本文的聚合条件下 ,大部分聚合的单体转化率都达 90 %以上 ,聚合产物的粘均分子量最高可达 6 6 0 0 0 ,均显示出较好的催化性能 .在PEG存在下 ,PEG作为引发剂参入了丙交酯的开环聚合 ,D ,L 丙交酯是沿着PEG分子两端开环聚合的 ,分子链的链端结构是以羟基为端基的乳酰基结构单元 ,Fe(acac) 3有促进PEG参与聚合成酯的作用 .  相似文献   

11.
The title coordination compound with N-substituted-salicyl Schiff ligand, Cu(C15H12N2O3)(C5H5N), has been synthesized. The coordination compound crystallizes in orthorhombic system, space group Pbca with a=2.037 62(7) nm, b=0.698 45(2)nm, c=2.508 76(9)nm, V=3.570 4(2) nm3, Z=8, F(000)=1 688, Dc=1.529 g·cm-3, Mr=410.91, μ=1.250 mm-1, R=0.031 3 and wR=0.077 0. In the coordination compound, one phenolate oxygen, one carbonyl oxygen and one hydrazine nitrogen atom from the dianionic ligand N-salicylaldehyde-N′-(4-methoxybenzoyl) hydrazone and one pyridine nitrogen atom coordinate to Cu(Ⅱ) ion, forming a distorted square plane. CCDC: 218182.  相似文献   

12.
The title complex Cu[C5H3N(CCH3=N-C6H5)2]2(PF6)2 has been synthesized by reaction of Schiff base C5H3N(CCH3=N-C6H5)2 and cupric sulfate in toluene solution. The crystal structure was determined by X-ray diffraction method and the chemical formula weight of the complex is 1041.85. The crystal structure belongs to triclinic system with space group P1 and cell parameters: a=12.6470(10)?, b=14.123(2)?, c=15.613(2)?;α=66.150(10)°,β=79.470(10)°,γ=78.290(10)°, V=2481.6(5)?3, Z=2, Dc=1.394Mg·m-3 and F(000)=1064. The final R[I >2σ(I)]:R1=0.0668, wR2=0.1927; R(all data): R1=0.1133, wR2=0.2357. The Cu(Ⅱ) was coordinated by six nitrogen, at the same time the Cu(Ⅱ) formed a distorted octahedron, besides the angles and planes of this compound were discussed . The result of kinetics of the thermal decomposition indicated that the first step of it is 2 series chemical reactions, the function of machanism is f(a)=(1-a)2, and the activation energy is 144.64E/kJ. CCDC: 180872.  相似文献   

13.
A novel nickel(Ⅱ) complex with 2,4-dihydroxybenzalidene benzoylhydrazone and pyridine ligands, Ni(C14H10N2O3)(C5H5N), has been synthesized and characterized by elemental analysis and IR. The crystal structure of the title complex has been determined by single crystal X-ray diffraction techniques. The crystal belongs to orthorhombic, space group Pbca. The cell parameters are: a=1.580 20(19) nm, b=1.362 18(16) nm, c=1.616 50(19) nm, and V=3.479 5(7) nm3, Z=8, Dc=1.497 Mg·m-3, μ(Mo)=1.139 mm-1, F(000)=1 616, R=0.032 9 and wR=0.077 0 for 2 772 observed reflections (I>2σ(I)) out of 3810 unique ones. The nickel(Ⅱ) ion lies in a distorted square-planar environment composed of two oxygen atoms, one nitrogen atom of tridentate acyhydrazone schiff base ligand and one nitrogen atom of the pyridine ligand. The analysis of the crystal structure indicates that the complex has a one-dimensional chain structure, which is formed by intermolecular hydrogen bonds. CCDC: 244668.  相似文献   

14.
0 引 言 Schiff碱及其金属配合物,因其具有较强的生物活性以及良好的催化作用而倍受人们的关注[1,2].  相似文献   

15.
The novel copper(Ⅱ) complex with salicylaldehyde benzoylhydrazone and pyridine ligands, Cu(C14H10N2O2)(C5H5N), has been synthesized and characterized by elemental analysis, IR and thermal analysis. The crystal structure of the title complex has been determined by single crystal X-ray diffraction techniques. The crystal belongs to monoclinic with space group P21/c. The cell parameters are: a=1.6362(9)nm, b=1.7140(9)nm, c=1.2255(7)nm, β=105.168(9)°, V=3.317(3)nm3Z=8, Dc=1.525g·cm-3, μ(MoKα)=1.334mm-1F(000)=1560. The structure was refined to final R1=0.0376, wR2=0.0909. The copper(Ⅱ) ion lies in a dis-torted square-planar environment composed of two oxygen atoms, one nitrogen atom of tridentate acyhydrazone Schiff base ligand and one nitrogen atom of the pyridine ligand. CCDC: 193111.  相似文献   

16.
Two new octahedral Cd(II) complexes [Cd(L)2] (1) and {[Cd(LH)2(SCN)2]H2O} (2) [where LH = C14H13N3O] are synthesized using a tridentate hydrazone ligand (LH) and they are characterized by elemental analysis, IR spectra, NMR spectra, thermal studies and finally the structures have been determined by single crystal X-ray diffraction. Complex 1 crystallizes in monoclinic system, space group C2/c with a = 22.565(6) ?, b = 10.252(3) ?, c = 12.187(4) ?, β = 118.851(2), and Z = 4. Complex 2 also crystallizes in the monoclinic system, space group P21/c with a = 9.257(9)?, b = 17.809(2)?, c = 9.548(9)?, β = 107.439(4), and Z = 2. In 1 the ligand binds the Cd(II) ion in tridentate fashion, whereas in 2 it acts as a bidentate ligand.  相似文献   

17.
The bright red title compound 1 was synthesized from (2-lithiophenyl)diphenylamine and bis(pentafluorophenyl)boron chloride. Its reactions with small acids like H2O and HCl proceeded easily giving zwitterionic compounds. For 1 and its water adduct 2 the crystal structures were determined, the latter featuring an ammonium borate structure containing a short intramolecular hydrogen bond bridge. Treatment of 1 with Jutzi's acid, [H(OEt2)2][B(C6F5)4], did not result in protonation of the nitrogen, but reaction of 1 with LiH in the presence of 12-crown-4, led to the isolation of the aminoborate [1-(Ph2N)-2-{B(H)(C6F5)2}C6H4][Li(12-crown-4)] (3). Borohydride 3 reacted with Jutzi's acid to regenerate 1 and liberate hydrogen.  相似文献   

18.
[TiCl2(salen)] (1) reacts with AlMe3 (1:2) to give the heterometallic Ti(III) and Ti(IV) complexes [Ti{(μ-Cl)(AlMe2)}{(μ-Cl)(AlMe2X)}(salen)] (X=Me or Cl) (2) and [TiMe{(μ-Cl)(AlCl2Me)}(salen)] (3). Addition of diethyl ether to 3 affords [Ti(Me)Cl(salen)] (4). The analogous reaction of [TiBr2(salen)] (5) gives the crystallographically characterised [Ti{(μ-Br)(AlMe2)}{(μ-Br)(AlMe2X)}(salen)] (X=Me or Br) (6) and [Ti(Me)Br(salen)] (7) in a single step, whilst the comparable reaction of [TiCl2{(3-MeO)2salen}] (8) with AlMe3 yields [Ti(Me)Cl{(3-MeO)2salen}] (9) with no evidence of titanium(III) species. Reactivity of both halide and methyl groups of 4 has been probed using magnesium reduction, SbCl5 and AgBF4 halide abstraction and SO2 insertion reactions. Hydrolysis of [Ti(Me)X(L)] complexes affords μ-oxo species [TiX(L)]2(μ-O) [X=Cl, L=salen (13); X=Br, L=salen (14); X=Cl, L=(3-MeO)2salen (15)].  相似文献   

19.
The inclusion of vanadocene dichloride (VDC) and 1,1′-dimethyl vanadocene dichloride (MeVDC) into cyclodextrines (α-CD, β-CD and γ-CD) was studied by EPR spectroscopy. It was found that VDC and MeVDC with β-CD and γ-CD form true inclusion compounds, but with α-CD, VDC and MeVDC gave only fine dispersion mixtures. The inclusion was validated by anisotropic EPR spectra of solid samples. In addition, the antimicrobial was validated by anisotropic EPR spectra of solid samples. In addition, the antimicrobial behavior (against E. coli) of each of the complexes was determined. It was established that not only did VDC and MeVDC cause elongation of E. coli, but also the new vanadocene inclusion complexes were effective in this regard.  相似文献   

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