在本論文中，我們利用手性氧釩催化劑搭配氧化劑TBHP生成並引導自由基在醇類溶劑中對乙烯基芳烴進行不對稱的1,2-烷氧基硫基化反應。在七種雜芳硫醇自由基試劑之初步檢測，挑選出鏡像選擇性最佳的2-巰基苯並噁唑進行後續研究。經過十一種柳醛C-3與C-5取代的手性氧釩催化劑以及一系列反應濃度、溫度、溶劑與氧化劑的優化，確立最佳化的反應條件。在八種醇類溶劑的測試後，確立反應對甲醇、乙醇、正丙醇、正丁醇與異戊醇等一級醇類溶劑的通用性；並以甲醇與五十種鄰、間、對不同單取代、雙取代以及苯並/雜芳並的乙烯基芳烴及三種不同取代基的2-巰基苯並噁唑進行搭配，在大部分的例子中可得到高度的立體選擇性（>80%）與中等（~60%）至良好（~80%）的產率，產率可高達92%，ee值可高達96%。我們推測了產物與副產物可能的反應機制，並搭配理論計算進行反應中間體與過渡態的鏡像選擇性探討，最終我們也利用X光單晶繞射儀確立一代表性產物的絕對立體化學。

In this thesis, we utilized chiral vanadyl catalysts to facilitate the asymmetric 1,2-alkoxy-sulfenylation of vinylarenes via a radical pathway in alcohol solvents, employing TBHP as the oxidant. Among seven heteroarylthio radical precursors screened initially, 2-mercaptobenzoxazole was selected for further investigation due to its superior enantioselectivity. Through optimization involving eleven chiral vanadyl catalysts and a series of parameters including reaction concentration, temperature, solvent, and oxidant, optimal reaction conditions were established. After being tested with eight alcohol solvents, the generality of the reaction towards primary alcohol solvents was confirmed. Utilizing methanol and fifty different vinylarenes, along with 2-mercaptobenzoxazole with various substituents, resulted in high enantioselectivity (>80%) with moderate (~60%) to good yields (~80%) in most cases, with yields reaching up to 92% and ee values up to 96%. Possible reaction mechanisms for the products and by-products were proposed, and the enantioselectivity of reaction intermediates was explored through theoretical calculations. Finally, the absolute stereochemistry of the products was confirmed using X-ray single-crystal diffraction analysis.

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