鋁金屬錯合物之設計與其應用在環酯類開聚合反應

Aluminum Complexes Design for the Ring Opening Polymerization of ε-Caprolactone and L-Lactide

Someswara Rao Kosuru(Someswara Rao Kosuru)

指導教授 ： 陳喧應

高雄醫學大學/生命科學院/醫藥暨應用化學系博士班/博士(2020年)

摘要

我們研究了帶有不同側基原子的酚鹽配體的鋁絡合物及其在環酯類單體開環聚合中的催化反應性。我們在這裡討論了配體的配位效應，幾何影響，電子效應和空間效應，以及它們對ε-己內酯和L-乳酸交酯開環聚合的影響。
因此，我們合成了一系列具有不同電子取代基的硫代苯酚配體，並結合了五個和四個配位的鋁配合物。獲得了帶有硫代二茂鐵酚鹽和硫醚酚鹽配體的鋁配合物的X射線衍射數據。與兩個THF分子締合的四個配位的Al錯合物表明，配位體的兩個硫原子在配位溶劑中均與Al分離。在溶液中，當基材接近金屬中心時，兩個硫原子都從Al中心解離，從而接受單體配位。我們檢查了ε-己內酯和L-丙交酯的開環聚合中所有Al配合物的催化反應性以及動力學研究。
在進一步的項目中，我們合成了帶有氨基酚鹽配體的鋁配合物，並通過氮原子配位效應和電子效應研究了它們的催化反應性。我們合成了三種類型的氨基酚鹽配體，包括ONNO（salan），ONO（氨基雙（酚鹽）和NO（吡咯烷酚鹽））以及不同的電子取代基，以及它們相關的鋁配合物。研究了ε-己內酯和L-乳酸交酯在開環聚合中所有Al配合物的催化活性。催化結果表明，推電子基團衍生的鋁配合物比拉電子基團取代的配體具有更高的反應性。在配體上具有推電子基團取代的Salan型鋁配合物顯示出高的催化反應活性，與那些拉電子基團的配體具有相同的催化活性。衍生自配體上具有給電子基團的四個配位鋁配合物的氨基雙（酚酸酯）和吡咯烷酚酸酯配體通過側基氮原子的離解顯示出比吸電子基團取代的配體衍生的鋁配合物更高的反應性

關鍵字

鋁金屬錯合物

並列摘要

We studied aluminum complexes bearing phenolate ligands with different pendant atoms and their catalytic reactivity in the ring opening polymerization of cyclic monomers. We addressed here, coordination effect, geometrical influence, electronic effect, and steric effect of the ligands, and their influence in the ring opening polymerization of ε-caprolactone and L-lactide.
Hereby, we synthesized a series of thiophenol ligands with different electronic substitutions and associated five and four coordinated aluminum complexes. X-ray diffraction data of aluminum complexes bearing thioferrocene phenolate and thioether phenolate ligands were obtained. The four coordinated Al complex associated with two THF molecules revealed that both sulfur atoms of ligands disassociated from the Al in coordinating solvent. In solution, when the substrate approached the metal center, both sulfur atoms disassociate from the Al center to accept monomer coordination. We checked catalytic reactivity of all Al complexes in the ring opening polymerization of ε-caprolactone and L-lactide and as well as kinetic studies.
Further project, we synthesized aluminum complexes bearing amino phenolate ligands and investigated the their catalytic reactivity through the nitrogen atom coordination effect and the electronic effect. We synthesized three types amino phenolate ligands, including ONNO (salan), ONO (amino bis (phenolate)), and NO (pyrrolidine phenolate) with different electronic substitutions, and their associated aluminum complexes. Catalytic reactivities of all Al complexes in the ring opening polymerization of ε-caprolactone and L-lactide were studied. The catalytic results revealed that electron donating group derived aluminum complexes showed high reactivity than electron withdrawing group substituted ligands. Salan type aluminum complexes with electron donating group substitution on ligands showed high catalytic reactivity those of electron withdrawing group ligands did,. Amino bis (phenolate) and pyrrolidine phenolate ligands derived four coordinated aluminum complexes with electron donating group on ligands showed higher reactivity through disassociation of the pendant nitrogen atom than the electron withdrawing group substituted ligands derived aluminum complexes did.

並列關鍵字

Aluminum Complexes

參考文獻

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