Site-selective C-H bonds functionalization

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K16314
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 47010:Pharmaceutical chemistry and drug development sciences-related
• Research Institution: Hokkaido University (2021); Kyoto University (2019-2020)
• Principal Investigator: morisaki kazuhiro 北海道大学, 薬学研究院, 助教 (80822965)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: C-H官能基化 / 遠隔位不斉誘導 / 超分子 / 不斉非対称化 / 選択性制御

Outline of Final Research Achievements

The aim of the study is to establish a novel concept that enables site-selective C-H functionalization of conformationally flexible molecules. We have developed new chiral dirhodium catalysts featuring bisimide moieties. The catalyst enables remote desymmetrization of long-chain bis(arenes) and prochiral rotaxanes, which are long standing challenge in asymmetric reaction. Mechanistic analysis suggested that (1) the catalyst forms a deep and enclosed chiral pocket around the active center, which restricts substrates' conformation, and (2) molecular recognition is likely to occur throughhydrogen bonding with the aromatic C-H bond of the complex and Lewis basic site of the substrates.

Free Research Field

有機合成化学

Academic Significance and Societal Importance of the Research Achievements

有機反応において反応性の制御は最も重要な課題である。一般に、反応性の制御は反応点近傍の環境を識別して行われる。一方で、反応点から離れた位置の差異を識別し反応を制御することは最も困難な課題として残っている。今回の研究で我々は、反応点から6結合以上遠隔位の識別や、共有結合で繋がってすらいない超分子の不斉認識に成功した。適用可能な反応や基質に制限はあるものの、世界に先駆け遠隔位認識による反応性の制御(不斉識別)を達成できた。