旭硝子財団 助成研究成果報告（2023）共有結合性有機構造体は，軽量かつ金属を含まない多孔性材料として注目されるが，合成法および構造解析法に制限があり発展途上である．本研究ではこれらの両者を解決すべく，ひずみを内在した革新的なモノマー設計・合成，および微小単結晶の構造解析技術である電子回折構造解析の改良を行った．モノマー合成の過程において，予期しない4員環形成反応を発見し，新たな高ひずみ芳香族化合物合成を達成した．電子回折構造解析においては，モノマーとなる巨大分子の構造解析に成功し，従来法であるX線では不可能な微小結晶に適用可能であることを示した．Covalent organic frameworks are attracting attention as lightweight and metal-free porous materials, but they are still under development due to limitations in synthetic methods and structural analysis methods. In this re-search, we performed innovative monomer design and synthesis with inherent strain and improved electron diffraction crystallography. In the process of monomer synthesis, we discovered an unexpected four-mem-bered ring-forming reaction, and achieved the synthesis of novel highly strained aromatic compounds. In elec-tron diffraction crystallography, we succeeded in the structural analysis of macromolecules, and demonstrated that this method can be applied to microcrystals, which is not possible with the conventional X-ray method.不斉情報は医薬品や有機材料の機能発現に関わるため，新しい不斉情報の制御法の開発は，有機合成手法の洗練された現在においても，重要な研究課題となっている．今回我々は，分子内のヒドリド転位を起点とする不斉転写法を利用した，ユニークな連続第四級不斉中心含有インドール誘導体の不斉合成法の開発に成功した．本手法の興味深い点は，用いるLewis酸触媒を切り替えることで，優先するジアステレオマーの“合成仕分け”が可能となることである．すなわち，Gd(OTf)3を触媒とした際にはメチル基とメトキシカルボニル基が同じ側にあるトランス体が優先するのに対し，Yb(OTf)3を用いた際にはシス体が優先して得られた．Development of novel asymmetric reaction is one of the important subjects even in modern synthetic organic chemistry. Herein we want to report a novel synthetic route to chiral indoles having two contiguous quater-nary stereogenic canters based on intramolecular hydride shift mediated chirality transfer strategy. The inter-esting point of the present method was the achievement of diastereodivergent asymmetric synthesis of target compounds. When a methy atropate derivatives having 2-methylpyrrolidine unit were treated with a catalytic amount of Yb(OTf)3, target indoles were obtained in high cis selectivities (cis:trans = >10:1). In sharp con-trast, trans-isomers were predominant when Gd(OTf)3 was employed as a Lewis-acid catalyst (cis:trans = 1:>10). Detailed investigations suggested that switching of the kinetic- and thermodynamic-control by the Lewis acid catalysts was the key factor in the present reaction system.30瀬川 泰知13Yasutomo SEGAWA森 啓二14Keiji MORI微小結晶の構造解析を基軸とする3次元有機共有結合ネットワークの開発（2021採択）Development of 3D covalent organic networks based on the structural analysis of microcrystals(Project 2021)分子内ヒドリド転位型不斉転写によるキラル物質合成（2021採択）Asymmetric synthesis based on hydride shift mediated chirality transfer approach(Project 2021)
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