四價錳錯合物之逐步還原與反應性之探討

本研究延續先前本實驗室任少緯學長之論文，以兩分子含磷硫之三牙配位基H2PS2與製備出錳錯合物MnIV(PS2)2，於室溫及空氣下穩定之四價錳錯合物，以CV電化學確定其可能存三價、二價之氧化態，並藉由還原劑CoCp2、KC8等，分別獲得二價三價之錳錯合物[MnIII(PS2)2]─ 、[MnII(PS2)2]2─ 晶體，以X-ray單晶繞射獲得其結構，並針對其不同的電子組態進行EPR、SQUID、NMR-Evans Methods鑑定。並且發現了錳三價錯合物中之硫醇基(Thiolate)配位基具有顯著的親核性質，因此以親電試劑(CH3)3OBF4作為甲基提供試劑，實現了硫醇基烷化的反應並獲得其結構[MnIII(PS2)(PSS-CH3)]，此反應於前週期過渡金屬是並不常見的，此結構也證實了[MnIII(PS2)2]錯合物所具有的反應潛力，未來希望能透過不同的烷基加成修飾，來達到活化此系列錯合物的效果。

關鍵字

四價錳錯合物；硫醇基烷化反應

並列摘要

This study was continued from the previous works in our groups. The manganese (IV) complex MnIV(PS2)2 which is stable under air and room temperature was synthesized by the dithiolate-phousphine tridentate ligands H2PS2. Cyclic voltammetry revealed the probability oxidation state of Mn(III) / Mn(II) are existing. The [MnIII(PS2)2] / [MnII(PS2)2] complex was reduced by CoCp2 / KC8. The molecular structure CoCp2[MnIII(PS2)2] and Na2[MnII(PS2)2] was acquired from the X-ray diffraction. The EPR, SQUID, NMR-Evans methods were used for the identification of their electron configuration. Furthermore, The significant nucleophilicity was found with the thiolate ligand of the [MnIII(PS2)2]. Therefore the electrophilic reagent (CH3)3OBF4 was used as a reagent for providing the methyl cation (Me+). The thiolate-alkylation was successful and the single crystal [MnIII(PS2)(PSS-CH3)] was obtained and the thiolate-alkylation with complex is not common early-transition metals. The result shows the potential for activating these series of complex through different alkyl addition.