【作者】 张晓文；

【导师】 尹双凤；

【作者基本信息】 湖南大学 ， 化学工程与技术， 2010， 博士

【摘要】 铋(Bi)是自然界中唯一兼具相对价廉、低毒和低放射性等特性的重金属元素,外围特征电子结构为4f145d106s26p3。铋及其化合物在医药、有机合成、催化等领域已有应用,而且呈现较好的发展前景。有机铋化学作为铋化学的重要分支,近三十年获得了一些发展。迄今为止,有机铋化学发展中存在的不足主要体现在以下几个方面：(1)常规有机铋化合物中的Bi-C键的稳定性较差,(2)所披露的有机配体只有少部分适合于构建有机铋化合物,以及(3)有机铋化合物的功效没有被发掘。由于铋的“绿色”特性,在现代化学化工“绿色化”的发展潮流以及人类社会“可持续发展”的要求和驱动下,开发新型有机铋功能化合物将具有重要的科学价值和可观的应用前景。针对有机铋化学发展的不足以及铋外围的特征电子结构,本论文设计和合成了11种含O、S、N配位原子的三齿有机配体,并以此配体研制了30种具有耐水耐空气特性的新型有机铋化合物。采用NMR、FT-IR、X射线单晶衍射、TG-DSC等多种表征技术对配体前驱体以及有机铋化合物的组成、结构和物化性质进行了分析表征,还探讨了其在抑制癌细胞增殖、CO2化学固定及酸催化反应中的应用,取得了以下主要研究结果和结论：(1)在配体前驱体合成方面：采用NBS (N-Bromosuccinimide)作为溴化试剂,以及碳酸钾或者有机胺作为中和剂,通过优化制备条件,高选择性和高产率地合成了9种含N、O或S配位原子的对称配体前驱体以及2种含N或S配位原子的不对称配体前驱体。(2)以含S、N配位原子的前驱体((2-BrC6H4CH2)2S、(2-BrC6H4CH2)2NR(R=tBu、C6H5和C6H11)合成了8种有机铋氯化物(S(C6H4CH2)2BiCl、tBuN(C6H4-CH2)2BiCl、C6H5N(C6H4CH2)2BiCl和C6H11N(C6H4CH2)2BiCl等)；通过引入具有生理活性的含锗丙酸基团,制备了三种新型有机铋锗丙酸盐(S(CH2C6H4)2Bi02C-(CH2)2GePh3、C6H5N(C6H4CH2)2BiO2C(CH2)2GePh3和C6H11N(C6H4CH2)2Bi02C-(CH2)2GePh3)。结构分析结果表明,与配位原子氮或者铋原子直接相连的取代基影响这些配合物中的Bi-S或Bi-N的键长,而且有机锗丙酸基团取代氯原子后使得Bi-S或Bi-N键增长。抗肿瘤实验结果显示,这些有机铋化合物对MGC-803胃癌细胞的抗增殖性能优于临床药物顺铂,而且含锗丙酸基团的有机铋化合物比有机铋氯化物具有更高的抗增殖活性,化合物S(CH2C6H4)2Bi02C(CH2)2GePh3的IC50值为0.7μM。因此,三价铋离子的合适配位能力和有机锗基团的引入有利于提高铋化合物的抗增殖活性。(3)以含S、N配位原子的有机铋氯化物(S(C6H4CH2)2BiCl、RN(C6H4CH2)2BiCl(R=tBu、C6H5和C6H11))合成了8种新型超高价有机铋氢氧化物和氧化物(S(C6H4CH2)2BiOH,RN(C6H4CH2)2BiOH(R=tBu、C6H5和C6H11),[S(C6H4CH2)2Bi]2O,[RN(C6H4CH2)2Bi]2O(R=tBu、C6H5和C6H11))；并探讨了它们吸收固定CO2的性能。有机铋氢氧化物、氧化物和碳酸盐在一定的条件下可以相互转化。吸收／解吸试验结果表明,超高价有机铋氧化物具有良好的CO2捕集性能。与通常使用的有机胺吸收剂相比,具有吸收速度快、无腐蚀性、再生温度和耗能低、操作条件温和等优点,是一类具有应用前景的吸收剂。(4)构建了由阳离子有机铋化合物[tBuN(CH2C6H4)2Bi]+[B(C6F5)4]-和四丁基碘化铵所组成的催化剂体系,发现它在较温和反应条件下可以高效催化CO2与环氧化物之间的偶联反应制备环状碳酸酯,环状碳酸酯的选择性接近100%,而且催化剂可以多次重复使用。通过考察催化剂组成和反应条件的影响规律,初步揭示了该类催化剂对此偶联反应的催化作用是通过酸碱协同机制实现的,即该催化剂良好的催化活性与有机铋阳离子合适的路易斯酸性紧密相关。(5)以含N配位原子的有机铋氯化物RN(C6H4CH2)2BiCl(R=tBu、C6H5和C6H11)与全氟磺酸银和四氟硼酸银反应合成了11种具有较强路易酸酸性的新型超高价有机铋化合物79～89(RN(C6H4CH2)2BiX(R=tBu、C6H5和C6H11；X=BF4、OSO2CF3、OSO2C4F9和OSO2C8F17)),并探讨了其催化应用性能。研究结果表明,86(C6H11N(C6H4CH2)2Bi(BF4))在甲醇的水溶液(CH3OH／H2O=9：1)中可以有效催化醛的烯丙基化反应,89(C6H11N(C6H4CH2)2Bi(OSO2C8F17))在水为反应介质时仍可以高效催化“一锅”三组分Mannich反应。此外,这两种催化剂对空气稳定,用量少,具有很高的化学选择性,可以多次重复利用,其催化活性与选择性受反应底物的影响较小,具有良好的应用前景。更多还原

【Abstract】 Bismuth, which has an external orbits electronic configuration of 4f145d106s26p3, is a nontoxic and noncarcinogenic element. Many Bi compounds are low in toxicity and can be safely used in many areas such as medicine, catalysis, and organic synthesis. In the past thirty years, as an important branch of bismuth chemistry, organobismuth chemistry had been widely developed. Up to now, the development of organobismuth chemistry has suffered from several shortcomings:(1) poor stability of Bi-C bonds in many organobismuth compounds, (2) only little fraction of the reported organic ligands are suitable for constructing organobismuth compounds, and (3) the functionalities of them have not been disclosed. From the standpoint of "Green Chemistry" and "Sustainable Development", it is envisaged that Bi compounds will find new scientific value and applications.Based on the character of external electronic configuration of Bi and the development of organobismuth chemistry,11 tridentate organic ligands bearing O, S or N atoms as coordination atoms and 30 new air-stable organobismuth compouds were synthesized. The structure and properties of the compounds were characterized by NMR, FT-IR, X-Ray single crystal diffraction, TG-DSC techniques, etc. Moreover, their potential applications in antiproliferative activity on cancer cell, CO2 fixation and Lewis acid catalyzed C-C bond forming reactions were investigated. Some innovative results and conclusions were obtained as follows.(1) Synthesis of ligand precursors:9 ligand precursors bearing N, O or S coordinating atoms and 2 asymmetric ligand precursors containing N or O coordinating atoms were synthesized in high yield and selectivity using 1-Br-2-CH3-C6H4 and 1-Br-2-CH3-C10H6 and NBS as starting raw material in the presence of K2CO3 or amine as neutralizing agent.(2) Eight organobismuth chlorides [S(C6H4CH2)2BiCl,tBuN(C6H4CH2)2BiCl, C6H5N(C6H4CH2)2BiCl, C6H11N(C6H4CH2)2BiCl et al.] were synthesized from the tridentate ligand precursors [(2-BrC6H4CH2)2S, (2-BrC6H4CH2)2NR(R=tBu, C6H5, C6H11) et al]. Three cyclic hypervalent organobismuth compounds bearing physiological activity organogermanium segment [S(CH2C6H4)2BiO2C(CH2)2GePh3, C6H5N(C6H4CH2)2BiO2C(CH2)2GePh3 and C6H11N(C6H4CH2)2Bi02C(CH2)2GePh3] were synthesized by the reaction of the organobismuth chlorides withβ-(triphenyl-germyl)-propionic acid in the presence of NaOH. Single crystal X-ray diffraction analysis results reveal that the Bi-S or Bi-N bond lengths in thiabismocine or azabismocine derivatives are dependent on the substituted groups which are acting on the N and Bi atom. The replacement of Cl atom by organogermanium segment leads to the lengthening of the Bi-S or Bi-N bonds. The six compounds show antiproliferative activities on MGC-803, better than that of cisplatin; and the IC50 value for compound S(CH2C6H4)2BiO2CCH2CH2GePh3 is 0.7μM. It is apparent that a proper coordination ability of Bi3+ and the introduction of organogermanium group are beneficial for achieving good antiproliferative activitves.(3) Eight cyclic hypervalent organobismuth compounds{S(C6H4CH2)2BiOH, RN(C6H4CH2)2BiOH(R=tBu, C6H5 and C6H11); [S(C6H4CH2)2Bi]2O, [RN(C6H4CH2)2-Bi]2O (R=tBu, C6H5 and C6H11)} were synthesized from the organobismuth chlorides [S(C6H4CH2)2BiCl, RN(C6H4CH2)2BiCl(R=tBu, C6H5 and C6H11)] bearing S, N coordination atoms. Four organobismuth carbonates{[S(C6H4CH2)2Bi]2CO3, [RN(C6H4CH2)2Bi]2CO3(R=tBu, C6H5 and C6H11)} were obtained through the reaction of CO2 with the organobismth oxides or hydroxides respectively. It was found that hydroxide, oxide and carbonate of organobismuth compounds can be mutually transformed under appropriate conditions. The results of adsorption/regeneration experiments indicated that these oxides showed high efficiency for the capture of carbon dioxide under relatively mild conditions. Compared with amine, this absorbent has the advantages such as high absorption capacity of carbon dioxide, no corrosion, low energy consumption and regeneration temperature. Therefore, it will find potential application in CO2 capture.(4) Cationic organobismuth complex [tBuN(CH2C6H4)2Bi]+[B(C6F5)4]- was the first time used to examine for the coupling of CO2 into cyclic carbonates, using terminal epoxides as substrates and tetrabutylammonium halide as co-catalyst in a solvent-free environment under mild conditions. It was shown that both of epoxide conversion and cyclic carbonate selectivity (near 100%) are high. The catalyst can be easily separated and reused with little decline in activity and selectivity. A plausible mechanism for the coupling reaction over [tBuN(CH2C6H4)2Bi]+[B(C6F5)4]-+Bu4NI has been proposed. The excellent catalytic performance is possibly related to proper Lewis acidity of the cationic organobismuth complex.(5) Eleven new hypervalent organobismuth(Ⅲ) compounds 79～89 RN(C6H4-CH2)2BiX(R=tBu, C6H5 and C6H11; X=BF4, OSO2CF3, OSO2C4F9 and OSO2C8F17) with strong Lewis acidity, were synthesized by the reaction of organobismuth chlorides RN(C6H4CH2)2BiCl(R=tBu, C6H5 and C6H11) with silver perfluorooctane -sulfonate and silver tetrafluorborate, respectively. C6H11N(CH2C6H4)2BiBF4 and C6H11N(C6H4CH2)2Bi(OSO2C8F17) were examined as catalysts for C-C bond forming reactions. It was found that 86 shows good catalytic efficiency in the allylation reaction with tetraallyltin in a medium of aqueous methanol (CH3OH/H2O=9:1), and 89 exhibits high catalytic efficiency towards one-pot Mannich-type reaction of ketones with aromatic aldehydes and aromatic amines in water. Furthermore, these two catalysts show good stability and recyclability, and is almost independed of the reactant substrates.更多还原