Synthesis of pai-conjugated enamines and nitrogen heterocycles by highly efficient iridium catalysts and their applications to functional materials

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K05058
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 33020:Synthetic organic chemistry-related
• Research Institution: Kyushu University
• Principal Investigator: Nagashima Hideo 九州大学, グリーンテクノロジー研究教育センター, 特任教授 (50159076)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 9族遷移金属触媒 / ヒドロシリル化反応 / 還元反応 / エナミン / DFT計算 / 反応機構 / 触媒サイクル

Outline of Final Research Achievements

Synthesis of enamines from amides using iridium catalysts and certain hydrosilanes, which have two closely located Si-H groups, is a useful reaction with extremely high activity and selectivity in homogeneous catalysis. In this project, we carried out applications of enamines obtained by the catalytic reaction to organic EL devices, development of new synthetic methods for indoles and pyrroles, and exploration of new catalysts for the hydrosilane reduction of carbonyl compounds with high catalytic activity and unique selectivity. DFT calculations were performed in order to propose reaction mechanisms that would explain the experimental results without contradiction. A new catalytic cycle called “disilametallacyclic mechanism” is established for the unique reactivity of the hydrosilanes having two closely located Si-H groups. A reasonable catalytic cycle for cobalt-catalyzed hydrosilylation of alkenes is also investigated.

Free Research Field

有機金属化学

Academic Significance and Societal Importance of the Research Achievements

ファインケミカル合成の鍵技術である均一系触媒においては、高い触媒活性と高い反応選択性を持つ反応の開発は、「元素減量」戦略としてSDGsの達成に貢献する。本研究では、イリジウム触媒を用いるアミドのヒドロシラン還元によるエナミン合成の展開として、複素環化合物の新規合成法の開発、新しい触媒の開発に成果を上げるとともに、計算科学を用いてヒドロシリル化の反応機構解明研究を通じて学術的な貢献をおこなった。また、社会的には、得られたエナミンを有機EL素子に応用する産学共同研究をにおいて成果を得た。