十六族碲三鐵羰基化合物與銅(I)及含氮異環碳烯或咪唑試劑之團簇化合物合成及其催化反應與混合十五族鉍與十六族硒之團簇化合物其反應性、電化學、電子吸收光譜與理論計算探討

Abstract

Te－Fe－Cu－L (L = NHC or N-alkyl imidazole) 系統 利用 [TeFe3(CO)9]2─、[Cu(MeCN)4][BF4] 和 1-methylimidazole (MeIm) 或在其骨架上修飾有苯環之 1-methylbenzimidazole (MeBzIm) 以 1: 1: 1 或 1: 2: 2 之莫耳比反應，可獲得一系列以咪唑為配基之碲三鐵羰基含銅 (I) 團簇化合物 [TeFe3(CO)9Cu(MeIm)]─ (1)、[TeFe3(CO)9Cu2(MeIm)2] (2)、[TeFe3(CO)9Cu(MeBzIm)]─ (3)、[TeFe3(CO)9Cu2(MeBzIm)2] (4)、[(TeFe3(CO)9Cu)2(BzIm)]3─ (7)，另合成結構相似但以氮異環碳烯為配基之化合物 [TeFe3(CO)9Cu2(Me2Im)2] (6)、[TeFe3(CO)9Cu2(Me2BzIm)2] (8)。本研究以電化學、電子吸收光譜等方法，來探究氮異環碳烯配基和咪唑配基以不同之模式鍵結以及於配基上修飾苯環與否，對金屬團簇化合物所造成之影響及兩者間之差異，並搭配 DFT 理論計算加以驗證。進而對此一系列化合物於同耦合催化反應做一比較。

E－Fe－Bi (E = Se, Te) 系統 當含十五/十六族之金字塔構型化合物 [SeBiFe3(CO)9]─ (1a) 於 MeCN 中進行加熱反應，可生成新穎之四面體化合物 [SeBiFe2(CO)6]─ (2a)。而與 2a 相同構型之化合物 [TeBiFe2(CO)6]─ (2b) 則可由 [TeBiFe3(CO)9]─ (1b) 和一當量 NaBiO3 於 MeCN 下加熱約 24 小時獲得。而當 1a 和另一氧化試劑 K2SeO3 以莫耳比 1: 1於 MeCN/MeOH下反應，則可生成以 4-Bi 連接雙蝴蝶結構 Se2Fe2(CO)6 之新穎化合物 [Bi(Se2Fe2(CO)6)2] (3)。此外，化合物 1a 可和 Ru3(CO)12 以 2: 1 之莫耳比反應生成混合主族、混合金屬之八面體化合物 [SeBiFeRu3(CO)11]─ (4)。除反應性探討外，也將過去一系列同核之 [E2Fe2(CO)6]、[E2Fe3(CO)9] (E = Se, Te) 和其等電子結構之異核化合物 [EBiFe2(CO)6]─ (E = Se, 2a; Te, 2b)、[EBiFe3(CO)9]─ (E = Se, 1a; Te, 1b)，以及相同八面體結構之化合物 [ERu5(CO)14]2─ (E = Se, Te) 和 [SeBiFeRu3(CO)11]─ (3)、[TeBiRu4(CO)11]─ 做平行比較，並藉由電化學、電子吸收光譜等方法分析探討引入混合主族對其整體化合物造成之影響及 Bi 所扮演之角色，並藉由 DFT 以及 TDDFT 對其電子結構、紫外-可見光光譜之電子躍遷組成進行分析與討論。

Te－Fe－Cu－L (L = NHC or N-alkyl imidazole) System When [TeFe3(CO)9]2─ was treated with [Cu(MeCN)4][BF4] and 1-methylimidazole (MeIm) or annulated 1-methylbenzimidazole (MeBzIm) in the molar ratio of 1: 1: 1 or 1: 2: 2, a series of Cu(I)-linked, TeFe3-based clusters bearing imidazole ligand(s) [TeFe3(CO)9Cu(MeIm)]─ (1), [TeFe3(CO)9Cu2(MeIm)2] (2), [TeFe3(CO)9Cu(MeBzIm)]─ (3), [TeFe3(CO)9Cu2(MeBzIm)2] (4), and [(TeFe3(CO)9Cu)2(BzIm)]3─ (7) were obtained. To investigate the influence on the electronic properties of NHCs and N-methyl imidazole ligands and the difference arisen from normal imidazole or annulated imidazole ligand in metal clusters, imidazole-containing complexes 2 and 4 were compared with NHC complexes [TeFe3(CO)9Cu2(Me2Im)2] (6) and [TeFe3(CO)9Cu2(Me2BzIm)2] (8) in terms of electrochemistry, UV-vis spectrum, and catalytic homo-coupling reaction with the aid of DFT calculations.

E－Fe－Bi (E = Se, Te) System When mixed group 15/16 square pyramidal cluster [SeBiFe3(CO)9]─ (1a) was refluxed in MeCN, a tetrahedral cluster [SeBiFe2(CO)6]─ (2a) was formed. Similar tetrahedral cluster [TeBiFe2(CO)6]─ (2b) could be generated from the reaction of [TeBiFe3(CO)9]─ (1b) with 1 equiv NaBiO3 in refluxing MeCN. The treatment of 1a with the oxidizing reagent, K2SeO3, in MeCN/MeOH solution could form a novel cluster [Bi(Se2Fe2(CO)6)2] (3) which displayed a double Se2Fe2(CO)6 butterfly structure with a bridging 4-Bi atom. In addition, complex 1a could react with Ru3(CO)12 in the molar ratio of 2: 1 to produce a mixed-metal octahedral cluster [SeBiFeRu3(CO)11]─ (4). To further investigate the influence of mixed group 15/16 elements and the role of Bi, a series of group 16 clusters, [E2Fe2(CO)6] (E = Se, Te) and [E2Fe3(CO)9] (E = Se, Te), were synthesized and compared with the isoelectronic mixed-main group clusters, [EBiFe2(CO)6]─ (E = Se, 2a; Te, 2b) and [EBiFe3(CO)9]─ (E = Se, 1a; Te, 1b), in terms of electrochemistry and UV-vis spectrum with the aid of DFT and TD-DFT calculations. Besides, the parallel comparison was also applied to [ERu5(CO)14]2─ (E = Se, Te) and its structural analogues [SeBiFeRu3(CO)11]─ (4) and [TeBiRu4(CO)11]─ via spectroscopic method and theoretical calculations.