近年由於光催化以及傳統催化機制的發展與深入，使光協同催化反 應成為一熱門的研究主題。光協同催化反應通常由光敏劑以及催化劑 組合而成，藉由光能代替傳統使用之熱能來驅動反應，其優點是減少高 溫帶來之副反應，以及增加設計新反應之可能性。本實驗室在 2015 與 2018 年發表一種鉗型同碳雙碳烯鈀錯合物，發現它能夠催化單電子的 光氧化還原及雙電子的偶聯反應。 使用此化合物於光誘導碳氫活化反 應，可以在不添加光敏劑的條件下進行，惟目前極少數的例子。此雙功 能的催化劑在這個研究的領域上為一個很重大的進展。 本論文以鉗型同碳雙碳烯鈀錯合物為研究的方向，對於此化合物進 行官能基的修飾，其中設計了具有電子效應及立體效應的兩種配位基， 在電子效應的部分，將具有推電子的甲氧基接在配位基上，使中心碳 的孤對電子的供電子能力增加，對於光氧化還原反應有正向的影響， 在立體效應的部分，將具有立體障礙的甲基接在配位基的吡啶上，使 反應位點的立體障礙增大，對於催化反應造成負面的影響，透過這些 研究所得到的資訊可以更深入的瞭解其反應機制並且發展更多此系統 的應用。 ;Recently, based on the accumulated understanding of photo-catalysis and conventional catalysis cycle, the combinatory synergistic catalysis become a topic of great interest. The cooperative photo-redox catalysis usually consists of a photo-sensitizer and an operating catalyst, in which photo energy is used to replace the thermal energy as the driving force. The advantages are reducing the side reactions caused by high temperature as well as increasing the possibility of designing a new state-of-art reaction. In 2015 and 2018, our lab has published the pincer-type carbodicarbene palladium complex, which is capable of catalyzing the photo-redox reaction (1e- process) and the cross-coupling (2e- process). This complex can also be utilized as both the photo-sensitizer and cross-coupling catalyst. This bifunctional catalyst is very rare and represents a significant advancement in this field of research. In this thesis, the research topic is to modify the pincer-type carbodicarbene palladium complex by designing two types of ligand for electronic effect and steric effect. To examine the electronic effect, the methoxy groups were installed on the ligand backbone to increase the sigma-donating ability. In the part of steric effect, the methyl group were installed on the ortho-position of the pyridine side-arms, blocking the trajectory of incoming substrate towards the metal center. With the information provided, we can understand mechanisms in details and develop more applications of this system.
