金屬含硫配位之錯合物在生物體內有許多重要的功能，例如：電子傳遞蛋白或感應氧化還原。我實驗室合成、鑑定出以下幾種釩硫錯合物：[VIII(PS3”)(PS2”SH)]- (1) ([PS2”SH]2- = [P(C6H3-3-Me3Si-2-S)2(C6H3-3-Me3Si-2-SH)]2-), [VIV(PS3”)(PS2”SH)]- (2) ([PS3”]3- = [P(C6H3-3-Me3Si-2-S)3]3-)、[V(PS3”)2]- (3)、[V(PS3”)(PS2”SH)] (4)、[VIV(PS3”)2]2- (5)、{[V(PS3”)2]2H}- (6)、以及[VIV(PS3”)(PS1”circle)L] (7) (L = H2O or CH3CN)。
錯合物1可被氧氣氧化為錯合物2，並進一步氧化為錯合物3，在此過程中伴隨著未配位之硫醇鍵之去質子化並配位。錯合物3也可由錯合物2逐步與FePF6及n-BuLi不限順序反應而得。而錯合物1則需在酸性條件下，將錯合物2與CoCp2反應得到。值得一提的是此一將配位之硫質子化成無配位之硫醇的過程中需要酸與還原劑同時存在的情況下反應，暗示了錯合物金屬中心之還原伴隨著配位之硫質子化成無配位之硫醇的關聯。
錯合物3為一在五價釩-硫與四價釩-硫自由基兩種結構共振的形式下存在，其被發現可以透過proton-coupled electron transfer (PCET)的反應機構活化水分子中的氫氧鍵，並產生錯合物2，而此反應之化學動力學將在本篇論文中研究與討論。
將錯合物3與弱酸或是與錯合物4以1:1混合，皆會產生錯合物6，其被推測為錯合物3與錯合物4藉由以S…H…S橋接二聚化之錯合物，但我們能需要更多的證據來證明這個假設。錯合物6並不穩定並且會進一步發生分子內反應形成錯合物2及錯合物7作為產物。

Metal thiolates play many roles such as electron transfer proteins and redox sensors in organisms. Here we present a series of non-oxido vanadium thiolate complexes, [VIII(PS2”SH)2]- (1) ([PS2”SH]2- = [P(C6H3-3-Me3Si-2-S)2(C6H3-3-Me3Si-2-SH)]2-), [VIV(PS3”)(PS2”SH)]- (2) ([PS3”]3- = [P(C6H3-3-Me3Si-2-S)3]3-), [V(PS3”)2]- (3), [V(PS3”)(PS2”SH)] (4), [VIV(PS3”)2]2- (5), {[V(PS3”)2]2H}- (6), and [VIV(PS3”)(PS1”circle)L] (7) (L = H2O or CH3CN).
Complex 1 is oxidized to complex 2 then to complex 3 with dioxygen. Each one-electron oxidation process is accompanied with the deprotonation of unbound thiol to bound thiolate. Complex 3 is also produced from complex 2 through step-wise addition of FePF6/n-BuLi, or in the reverse order. The formation of 1 from 2 is achieved in the order of adding CoCp2 and acid or, as with the previous complex, inversely. Notably, the reduction of complex 2 to complex 1 accompanying the protonation of bound thiolate to unbound thiol only occurs with the presence of both CoCp2 and acid, indicating a cooperative effect between the metal-centered reduction and bound thiolate protonation.
Complex 3 is a resonance form of VV-thiolate and VIV-thiyl radical species and it is found to activate O-H bond in H2O to form complex 2 via proton-coupled electron transfer (PCET) mechanism, the kinetic studies of this reaction is ad-dressed.
While complex 3 reacting with weak acid, an intermediate (complex 6) is formed. Alternatively, the reaction of complex 3 with complex 4 also leads to the formation of complex 6. Complex 6 is proposed as a dimerized form of complex 3 and 4 with S…H…S acting as a bridge between two species. More evidences need to be collected to support this hypothesis. Complex 6 is a metastable species and it further proceeds an intramolecular reaction to form complex 2 and complex 7.

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