Dynamic Stereochemical Control by Using Lewis Acid Base Active Species

在本研究项目中，我们的重点是设计真正重要的合成催化剂，以开发刘易斯酸/碱活性物质，以实现高选择性的立体化学控制。也就是说，Maruoka研究了前所未有的螯合型五配位硼配合物和双齿刘易斯酸化学。在后一种化学中，成功地设计了一种新的手性双齿Ti （IV）配合物，可以用于同时配位醛羰基，从而允许对这些羰基进行精确的对映面识别，从而实现一种新的催化的、实用的对映选择性醛与烯丙基三丁基锡的烯丙基化。Ooi制备了（2,7-二甲基-1,8-联苯二氧基）双（二甲基铝）和（蒽醌-1,8-二氧基）双（三异丙氧基钛）双齿刘易斯酸，用于同时配位羰基底物。与单齿试剂相比，强调了双齿有机铝和钛试剂对碳离子的高同时配位能力，并通过评价酮类底物在几种亲电反应中的双亲电活化来表征。Kakuchi将1,2,4,5 -二氢戊醇的环聚合应用于手性固定相，并阐明了氨基酸的光学分辨机理。Inanaga设计了手性稀土金属配合物，作为热力学稳定的单活性物质，用于应用不对称转化。植村通过使用金属阳离子交换蒙脱土催化剂，发展了烯烃的friedel - crafts型反应和醇的氧化反应。Shionoya通过金属络合合成了一种用于DNA碱基替代配对的新型核苷，并通过吖啶悬置Zn(II)-环素配合物的超分子自组装对对苯二甲酸进行了分子识别。Tomooka发展了对映选择性碳阴离子反应和对映选择性自由基反应来影响有机锂的动态立体化学控制。少

In this research project, we focused our attention on the design of truly important synthetic catalysts for the development of Lewis acid/base active species in order to achieve the highly selective stereochemical control. Namely, Maruoka studied unprecedented chelate-type pentacoordinate boron complexes and the bidentate Lewis acid chemistry. In the latter chemistry, a new, chiral bidentate Ti (IV) complex was successfully designed and can be utilized for simultaneous coordination to aldehyde carbonyls, thereby allowing the precise enantioface discrimination of such carbonyls for a new catalytic, practical enantioselective allylation of aldehydes with allyltributyltin. Ooi prepared (2,7-dimethyl-1,8-biphenylenedioxy)bis(dimethylaluminum) and (anthraquinone-1,8-dioxy)bis(triisopropoxytitanium) as bidentate Lewis acids for the simultaneous coordination to carbonyl substrates. The high, simultaneous coordination ability of the bidentate organoaluminum and titanium reagents toward carbony … More ls is emphasized in comparison with the corresponding monodentate reagents, and characterized by evaluating the double electrophilic activation of ketonic substrates in several electrophilic reactions. Kakuchi used the ring polymerization of 1,2 : 4,5-dianhydropentitol for the application to the chiral stationary phases and the elucidation of the optical resolution mechanism of amino acids. Inanaga designed chiral rare-earth metal complexes as thermodynamically stable, single active species for applying asymmetric transformations. Uemura developed the Friedel-Crafts-type reactions of alkenes and the oxidation reactions of alcohols by using metal cation-exchanged montmorillonite catalysts. Shionoya synthesized a novel nucleoside for alternative DNA base pairing through metal complexation, and carried out the molecular recognition of terephthalic acids by supramolecular self-assembly of acridine-pendant Zn(II)-cyclen complex. Tomooka developed the enantioselective carboanion reactions and the enantioselective radical reactions for effecting the dynamic stereochemical control of organolithium species. Less