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钳形镍金属化合物的合成及催化的Michael加成和Suzuki-Miyaura交叉偶联反应

The Synthesis of Pincer Nickel Complexes and Their Applications in Michael Addition and Suzuki-Miyaura Cross-Coupling Reaction

【作者】 邵丹丹

【导师】 宋毛平;

【作者基本信息】 郑州大学 , 有机化学, 2011, 硕士

【摘要】 本论文通过直接C-H键活化法简便的制得了五种NCN型Ni钳形金属化合物3a-e、两种PCN型Ni钳形金属化合物9b-10b、两种非对称PCP型Ni钳形金属化合物11b-12b。化合物3a、3c与AgBF4反应后可得到两种阳离子态Ni钳形金属化合物4a、4c。考察了化合物4a、4c在Michael加成(腈基丙酸乙酯与甲基乙烯基酮)反应中的催化活性和不对称选择性,化合物3a、4c、9b-12b在Suzuki-Miyaura偶联(对甲苯磺酸芳基酯与芳基硼酸)反应中的催化活性。根据文献合成酰胺基醇1a-c及双咪唑啉基苯2a-c,利用相似的方法合成化合物1d及化合物2e-f,即由双酰氯和胺基醇为起始原料在THF中三乙胺存在条件下反应生成双酰胺基醇,双酰胺基醇在SOCl2中回流后除去过量SOCl2加乙醚溶解过滤,滤液中加胺及对甲苯胺室温搅拌数小时后加NaOH溶液关环即生成双咪唑啉基苯。化合物2e-f与无水NiCl2在甲苯中回流直接金属化可得到二价N1钳形金属化合物3a-e。化合物3a和3c与AgBF4反应可得到阳离子态化合物4a和4c。化合物1d、2e-f、3a-e及4a和4c均经过IR、NMR.元素分析(或高分辨质谱)等分析手段表征,其中化合物3a-c和化合物4c经x-单晶衍射进一步确认其结构。根据文献合成化合物8、利用与文献相似的方法合成化合物10a、NaBH4还原间羟基苯甲醛得到间羟基苄醇,之后采用一锅法以Ph2PCl为P源、无水NiCl2为Ni源,通过直接金属化法合成不对称钳形金属化合物9b-12b。化合物9b-12b经IR、NMR、元素分析、x-单晶衍射等分析手段表征。研究了阳离子态化合物4a和4c对Micheal加成反应的催化活性及选择性(如Scheme 4中式(A)),结果表明化合物4a和4c对该反应均有很高的催化活性(产率可优化至>99%),但不对称选择性很差(ee值为0)。将化合物3a、4c、9b-12b用于催化Suzuki偶联反应,以对甲苯磺酸α-萘酯与苯基硼酸的偶联反应为模版反应(如Scheme 4中式(B))详细研究了催化剂配位杂原子、外加P配体、溶剂、碱等对该反应的影响并在最优条件下进行了底物拓展。

【Abstract】 In this thesis, five neutral chiral pincer NCN-Ni complexes 3a-e, two neutral pincer PCN-Ni complexes 9b-10b, and two neutral, asymmetric pincer PCP-Ni complexes llb-12b were synthesized by direct metalation via the C-H activation of the related ligands.Two cationic complexes 4a and 4c were obtained from the reaction of 3a and 3c with AgBF4. On one hand we studied the catalytic activities of cationic complexes 4a and 4c in the Michael addition of ethyl 2-cyanopropanoate to methyl vinyl ketone, on the other hand the catalytic activities of complexes 3a,4c, and 9b-12b in the Suzuki-Miyaura cross-coupling reaction of Aryl Tosylates with aryl boronic acids were studied too.Three known bis(amido) alcohols la-c and three Phebim-H ligands 2a-c were prepared using the published procedure. Complexes 1d and 2e-f were synthesized using an analogous procedure. The neutral Ni(Phebim)Cl complexes 3a-e could be conveniently prepared by direct C-H activation of the related Phebim-H ligands 2a-e and anhydrous NiCl2 in good yield. Reacting 3a and 3c with AgBF4 could give cationic complexes 4a and 4c, respectively. Complexes Id,2e-f,3a-e,4a and 4c were well characterized by IR spectra, NMR, elemental analysis(or HRMS) et al. The molecular structures of 3a-c and 4c were determined by X-ray single crystal analysis. Complexes 8 and 10a were synthesized using the published or analogous procedure. m-hydroxylbenzoicalcohol was obtained from the reduction of m-hydroxylbenzaldehyde by NaBH4, followed by one-pot phosphorylation/metalation reaction with diphenylchlorophosphine and anhydrous NiCl2, resulting in the aymmetric pincer complexes 9b-12b.These complexes were well characterized by IR spectra, NMR, elemental analysis, X-ray single crystal et al. The catalytic activities of cationic complexes 4a and 4c in the Michael addition((A) in Scheme 4) of ethyl 2-cyanopropanoate to methyl vinyl ketone were investigated. Complexes 4a and 4c were found to be effective catalysts with a catalyst loading of 5 mol%, producing the adduct in>99% yield with no ee. Complexes 3a,4c and 9b-12b were used to catalyze the Suzuki-Miyaura cross-coupling reaction((B) in Scheme 4), and we discussed the influence of the heteroatoms in the side arms of catalysts, additional P ligands, solvents, and different bases on these reactivities. Then, a series of Aryl Tosylates were tested under the optimized conditions.

  • 【网络出版投稿人】 郑州大学
  • 【网络出版年期】2012年 04期
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