含主族 (硫、硒、碲) 之過渡金屬 (鉻、鉬、鎢、錳、鐵) 團簇化合物的反應性、電化學、電子吸收光譜與理論計算

Abstract

1. E/Cr/CO (E = S, Se) 系統之研究 當雙三角錐化合物 [Se2Cr3(CO)10]2— (1a) 與 M(CO)6 (M = Mo, W) 以莫耳比 1：4 於無水丙酮加熱反應 (superheating)，可進行金屬取代反應而進一步形成 [Se2M3(CO)10]2— (M = Mo, 1b; W, 1c) 與含 hydride 扭曲立方體之化合物 [H2Se2Mo4(CO)12]2— (2a) 或具有 W=O 官能基之 [Se3W4(CO)12O]2— (3a)。化合物 2a 藉由 1H NMR 與 2D NMR 證實其 hydride 來源為水，並於反應前外加過量水可將產率提升。再者，化合物 3a 其氧原子來源也可藉由外加水或與氧氣證實之。此外，在 S 系統中以 [S2Cr3(CO)10]2— (4) 與 M(CO)6 (M = Mo, W) 於相似條件下反應，也可得與 Se 系統相似之 dihydride 化合物 [H2S2Mo4(CO)12]2— (2c) 與有 W=O 鍵結之 [S3W4(CO)12O]2— (3b)。然而，若將溫度降低至 40 oC，則獲得 Mo 單取代之 [Cr(CO)5S2Cr2Mo(CO)15]2— 與 [S2Cr2Mo(CO)10]2—。其化合物生成、相關性質與電化學藉由理論計算進一步驗證。

2. Te/Mn/Fe/CO 系統之研究 混合 Te 粉末、Mn2(CO)10、Fe(CO)5 與 PPNCl 以 2：1：2：2 之比例，在 KOH 鹼性甲醇溶液加熱 (superheating)，得四角錐構型之混合錳鐵化合物 [Te2Mn2Fe(CO)9]2— (1)。進一步當化合物 1 加入 Fe(CO)5 以莫耳比 1：1 於混合二氯甲烷及甲醇之鹼性溶液 (1 M) 在室溫下反應，可擴核形成八面體結構之混合錳鐵團簇物 [Te2Mn2Fe2(CO)11]2— (2)。然而，相似條件下提高溫度至 50 oC 可得蝴蝶形構型之化合物 [TeMn2Fe2(CO)12]2— (3)。此外，化合物 2 與 3 存在其結構轉換關係。其化合物之生成及結構鑑定藉由理論計算進一步佐證。

關鍵字: 過渡金屬、羰基化合物、氧氣、水1. E/Cr/CO (E = S, Se) System Superheating the trigonal-bipyramidal cluster (TBP), [Se2Cr3(CO)10]2— (1) with M(CO)6 (M = Mo, W) in a molar ratio of 1: 4 in acetone solution afforded four homonuclear clusters via metal-metal exchanged reactions, including clusters [Se2M3(CO)10]2— (M = Mo, 1b; W, 1c), the dihydride-capped distorted tetrahedral-like cluster [H2Se2Mo4(CO)12]2— (2a), and an oxo supported cluster [Se3W4(CO)12O]2— (3a). The source of the hydrides in 2a was derived from water molecules which confirmed by 1H NMR or 2D NMR, and the yield of 2a was increased by further addition of excess H2O. Besides, the source of the oxygen atom of the W=O functional group in 3a was likely derived from H2O or O2, in which the tungsten-oxo bond was fully characterized by spectroscopic methods. Additionally, in the sulfur system, the similar reaction of [S2Cr3(CO)10]2— (4a) with M(CO)6 (M = Mo, W) led to the analogous cluster [H2S2Mo4(CO)12]2— (2c) and [S3W4(CO)12O]2— (3b). However, if the reaction temperature was carried out at 40 oC, the sulfur-bonded-Cr(CO)5 cluster [{Cr(CO)5}S2Cr2Mo(CO)15]2— (5) and the TBP cluster [S2Cr2Mo(CO)10]2— (6) were obtained. The nature, formation and electrochemistry of these complexes were further elucidated by DFT calculations.

2. Te/Mn/Fe/CO System The reaction of Fe(CO)5 with a mixture of Te powder, Mn2(CO)10, and PPNCl in the concentrated KOH/MeOH solution produced the square-pyramidal mixed Mn-Fe cluster, [Te2Mn2Fe(CO)9]2— (1). Further, when 1 was treated with Fe(CO)5 in a molar ratio of 1：1 in mixed KOH/MeOH/CH2Cl2 solutions at room temperature, the octahedral-like cluster [Te2Mn2Fe2(CO)11]2— (2) was formed. However, the similar reaction was carried out at 50 oC, the butterfly-like cluster [TeMn2Fe2(CO)12]2— (3) was produced. In addition, the structural transformation of clusters 2 and 3 were achieved. The formation and geometric structures of these complexes were further elucidated by DFT calculations.

Keyword: Transition metal, Carbonyl, oxygen, H2O