萘啶銠金屬錯合物之合成與氫轉移反應的催化活性

本論文中探討萘啶-吡啶-五甲基環戊二烯基銠金屬錯合物的合成、結構鑑定與催化反應。以新發展出之萘啶-吡啶衍生物做為配基，與二氯(五甲基環戊二烯基)銠金屬二聚體反應形成預期之銠金屬錯合物8-10。利用核磁共振光譜、高解析質譜儀以及X光單晶繞射分析其結構，可得知銠金屬中心由萘啶-吡啶以及五甲基環戊二烯基配位，萘啶上之胺基或醯胺基並未配位於金屬中心，為外圍含有一個氯離子之陽離子型錯合物。此系列銠金屬錯合物可應用於氫轉移反應，利用甲酸/甲酸鈉或異丙醇為氫來源試劑還原喹啉與苯乙酮，並有良好的催化活性。銠金屬錯合物8與9對水皆有很好的溶解度，可選用水做為溶劑進行反應，符合綠色化學之期待。此外，8與9在空氣中相當穩定，能在大氣下進行催化反應。為了探討配位基萘啶上之醯胺基是否會對反應造成影響，製備了具有胺基之銠金屬錯合物9以及無取代之10，比較不同配位基銠金屬錯合物間之催化活性。

關鍵字

萘啶；銠金屬；氫轉移反應；催化反應

並列摘要

In this work, we have explored the syntheses, characterizations and catalytic activities of rhodium complexes containing both pentamethylcyclopentadienyl (Cp*) group and naphthyridine-based ligands. Upon the reaction between naphthyridine-based ligands and [Cp*RhCl2]2 afforded the cyclometalated Rh(III) cationic complexes. Rh(III) complexes display good activities on catalytic transfer hydrogenation reactions. Quinoline can be reduced into 1,2,3,4-Tetrahydroquinolines (THQs) with HCOOH/HCOONa as the hydride source under ambient condition in water. In addition, we also found that Rh(III) complexes have the catalytic activities on reduction of ketones to corresponding alcohols with isopropanol as the hydride source. We further confirmed the reaction pathway of quinoline reduction and proposed a mechanism. Last but not least, we compared catalytic activities of Rh(III) complexes with pendent amide or amine groups on the naphthyridine-based ligand on acetophenone reduction reaction.