【作者】 赵大鹏；

【导师】 母瀛；

【作者基本信息】 吉林大学 ， 有机化学， 2010， 博士

【摘要】 本论文介绍了一种由钛化合物参与的新型连续偶联反应,利用此反应合成了一系列未见文献报道的对称、不对称顺式二氢邻菲二胺及其钛配合物,利用低温核磁氢谱研究了反应机理,用三种顺式二氢邻菲二胺与三甲基铝反应得到三种不同结构的铝配合物,通过元素分析、核磁共振和X-射线晶体结构测定等手段对所合成的化合物进行了结构表征。在第二章中研究以TiCl4与邻溴苯基亚胺类化合物的锂盐按摩尔比1：2或1：3反应,经过分子内连续的还原消除和氧化偶联过程,合成了6个新型的9,10-二氢顺式二氢邻菲二胺钛配合物,以TiCl4与邻溴苯基亚胺类化合物的锂盐按摩尔比1：1反应合成了3个新的苯基亚胺钛配合物,并详细研究了反应条件对反应产物及产率的影响。在低温(-50℃)下用核磁氢谱同步监测TiCl4与2当量的锂盐ortho-C6H4(CH=NR)Li [R= 2,6-’Pr2C6H3]的反应,发现了一些有助于理解反应机理的信息。在第三章中研究以TiCl2(O’Pr)2与邻溴苯基亚胺类配体的锂盐按摩尔比1：2反应,合成了未见文献报道的3个对称、2个不对称顺式9,10-二氢邻菲二胺钛配合物,改进了反应条件,提高了合成产率,并分离到2个具有同时含对称的顺式二氢邻菲二胺和不同取代基苯基亚胺配体的钛配合物。在第四章中合成了5个顺式二氢邻菲二胺化合物,并分离到7个其它类型的化合物。通过对这些化合物结构的分析,提出了形成不同结构化合物的机理,说明了取代基团和反应条件影响反应产物及产率的原因。由于顺式二氢邻菲二胺配体衍生物具有较大的空阻,分子构象转换过程较慢,显示出特殊的核磁共振波谱,对其进行了详细的研究。在第五章中用AlMe3和三种不同取代基的顺式9,10-二-氢邻菲二胺等摩尔比反应,分离得到三种不同类型的A1配合物,其结构经X-射线晶体结构分析确认。以ZrCl4与顺式9,10-二(2,6-二异丙基苯胺基)-9,10-二氢邻菲二胺等摩尔比反应,分离得到两分子配体同时配位的Zr配合物。更多还原

【Abstract】 Carbon-carbon bond-forming reactions have been one of the most active research areas in organic and organometallic chemistry. In particular, transition metal mediated carbon-carbon bond-forming reactions have been extensively studied for constructing the basic carbon backbone of small organic molecules and extended polymeric structures. Mechanistic studies for the transition metals mediated C-C bond-forming reactions indicate that the stoichiometric and catalytic C-C bond-forming reactions mediated by mid-and late-transition metals can take place through several pathways, such as reductive elimination, oxidative coupling, migratory insertion,σ-bond orπ-bond metathesis, while the reactions mediated by group 4 metals go mainly through the migratory insertion pathway, which operates without requiring redox changes at the metal center such as the cases happen in the Ziegler-Natta polymerization reactions. The group 4 metals also mediate C-C bond-forming reactions through the reductive elimination process. However, most commonly observed C-C bond-forming reductive elimination reactions involving group 4 metal complexes are the coupling reactions of alkyl, acyl, and 1-alkenyl groups. For the aryl-aryl bond-forming reductive elimination reactions mediated by group 4 metals, only very few examples have been reported so far although the analogous process on group 10 metals is well documented. On the other hand, the oxidative coupling of unsaturated organic compounds on low valent group 4 metals is an efficient pathway for the construction of carbon-carbon bond. In the oxidative coupling reactions, the low valent group 4 metals, such as Ti (II) or Zr (II) reagents, are usually generated by treatment of Ti (IV) or Zr (IV) complexes with Grignard or organolithium reagents, followed by a reductive elimination process. In principle, both the reductive elimination and oxidative coupling processes can be used to construct carbon-carbon bond. However, there is no example of forming two C-C bonds in one molecule utilizing the sequential reductive elimination and oxidative coupling reactions. Recently, in the attempt to synthesize a type of new titanium complexes, [ortho-C6H4(CH=NR)]2TiCl2, as potential olefin polymerization catalysts, some new titanium complexes with a cis-9,10-dihydrophenanthrene diamide ligand were obtained in high yields. These new titanium complexes are obviously produced through the sequential C-C bond-forming reductive elimination and oxidative coupling reactions from the original formed complexes [ortho-C6H4(CH=NR)]2TiCl2. To the best of our knowledge, this is the first example of utilizing such a sequential C-C bond-forming process to synthesize complexes of this type.In chapter two, six new titanium (IV) complexes with cis-9,10-dihydrophen anthrenediamide ligands, have been synthesized from the reactions of TiCl4 with 2 or 3 equiv of corresponding ortho-C6H4(CH=NR)Li by sequential intra-molecular C-C bond-forming reductive elimination and oxidative coupling reactions. Attempts to isolate the intermediates, [ortho-C6H4(CH=NR)]2 TiCl2 were unsuccessful. By following the reaction of TiCl4 with 2 equiv lithium salt of la at-50℃with 1H NMR spectroscopy, useful information for understanding the reaction mechanism was obtained.In chapter three, three symmetric and two asymmetric titanium (IV) complexes with cis-9,10-dihydrophenanthrenediamide ligands, have been synthesized from the reactions of TiCl2(O’Pr)2 with 2 equiv of same or different corresponding ortho-C6H4(CH=NR)Li by sequential intra-molecular C-C bond-forming reductive elimination and oxidative coupling reactions. Two new titanium (IV) complexes with ortho-metalated arylimine and symmetric cis-9,10-dihydrophenanthrenediamide ligands [cis-9,10-PhenH2(NR1)2] NR2)] TiO’Pr [R1= 2,6-iPr2C6H3, R2=2,6-Et2C6H3; R1=2,6-iPr2C6H3, 2,6-Me2C6H3], were also isolated from the synthetic systems for TiCl2(O’Pr)2 with 2 equiv of different corresponding ortho-C6H4(CH=NR)Li.In chapter four, five new cis-9,10-dihydrophenanthrenediamide compounds and seven other interesting compounds have been synthesized and isolated from the reactions of TiCl2(O’Pr)2 with 2 equiv of same or different corresponding ortho-C6H4(CH=NR)Li by sequential intra-molecular C-C bond-forming reductive elimination and oxidative coupling reactions. All different molecular structures of these compounds were determined by X-ray crystallography, 1H and 13C NMR spectroscopy. The special NMR spectroscopy of cis-9,10-dihydrophenanthrenedi amide derivatives due to the slow conformational change and its substituent group effect have been researched by variable-temperature NMR spectroscopy.In chapter five, three diffenent structures of Al complexes with cis-9,10-dihy drophenanthrenediamide ligands have been synthesized by AlMe3 with three cis-9,10-dihydrophenanthrenediamide ligands due to the different steric hinderance of different substituent group and characterized by elemental analysis, NMR spectra, and single crystal X-ray diffraction.更多还原