含主族(鉛、硒、硫)與第六/八族羰基團簇化合物之合成、反應性及理論計算探討

Main Group (Pb, Se, or S)-Containing Group 6/Group 8 Carbonyl Clusters: Synthesis, Reactivities, and Theoretical Calculations

許妙行(Miao-Xing Xu)

指導教授 ： 謝明惠教授

國立臺灣師範大學/理學院/化學系/博士(2006年)

摘要

中文摘要
1. Pb/Cr/CO 系統之研究
將 PbCl2 與 Cr(CO)6 以1：2的比例，在 KOH 鹼性甲醇溶液中藉由陽離子 [Et4N]Br 交換反應可得新穎的氫氧根橋接雙聚合之鉛鉻羰基化合物 [Et4N]2[{PbCr2(CO)10}2(?-OH)2]。藉由反應條件控制，一個二氧化碳分子能插入反應至陰離子化合物[{PbCr2(CO)10}2(?-OH)2]2─而形成兩個新型的碳酸鹽化合物 [Et4N]2[{PbCr2(CO)10}(CO3)] 和 [Et4N]2[{PbCr2(CO)10}2(CO3)]。化合物 [{PbCr2(CO)10}- (CO3)]2─ 和 [{PbCr2(CO)10}2(CO3)]2─ 皆能於適當的控制下轉變回含氫氧根之化合物 [{PbCr2(CO)10}2(?-OH)2]2─。其反應性及生成藉由理論計算進一步驗證。

2. Pb/Cr/M/CO (M = Fe, Ru) 系統之研究
將 PbCl2、Cr(CO)6 與 Fe(CO)5 於 KOH 鹼性甲醇溶液中，藉由陽離子 [Bu4N]Br 交換反應可得新型化合物 [Bu4N]2[Pb{Cr(CO)5}{Fe(CO)4}2]。同構形鉛之鉻化合物 [Pb{Cr(CO)5}3]2─ 亦能利用相似的方法得到。化合物 [Pb{Cr(CO)5}3]2─ 與 Mn(CO)5Br 反應可形成以 Cr(CO)4 橋接雙聚合之鉛鉻羰基化合物 [Et4N]2[Pb2Br2Cr4(CO)18]，而其進一步與 Mn(CO)5Br 反應可得到已知化合物 [PbBr2Cr2(CO)10]2─。另一方面，平面結構之化合物 [Pb{Fe(CO)4}3]2─ 與 [Pb{Cr(CO)5}{Fe(CO)4}2]2─ 與 Mn(CO)5Br 反應會分別形成以 Fe3Pb2-雙三角錐為主體之化合物[Et4N]2[Fe3(CO)9{PbFe(CO)4}2] 與 [Et4N]2[Fe3(CO)9{PbCr(CO)5}2]。然而，以 Ru3Pb2-雙三角錐為主體之化合物 [Et4N]2[Ru3(CO)9{PbCr(CO)5}2] 能直接藉由 PbCl2、Cr(CO)6 與 Ru3(CO)12 於 KOH 鹼性甲醇溶液中，藉由陽離子 [Et4N]Br 交換反應得到。其生成、反應性及電化學分析利用理論計算進一步驗證。

3. Se/M/CO (M = Cr, Mo, W) 系統之研究
當 [Se2Cr3(CO)10]2─ 與4當量 Mo(CO)6 於丙酮溶液中加熱迴流反應，可得到 Mo 取代 Cr 之封閉型產物 [Et4N]2[Se2Mo3(CO)10]。若將 [Se2Cr3(CO)10]2─ 與4當量 W(CO)6 於丙酮溶液中加熱迴流反應，可得到一開放型平面結構化合物 [Et4N]2[Se2W4(CO)18]，若繼續加熱則可進一步合環形成 [Et4N]2[Se2W3(CO)10]。此外，[Se2Mo3(CO)10]2─ 與 [Se2W3(CO)10]2─ 亦可藉由單取代之產物 [Et4N]2[Se2Cr2M(CO)10] (M = Mo、W) 與3當量 M(CO)6 (M = Mo、W) 於丙酮溶液中反應得到。第六族過渡金屬之同核及異核產物之生成及結構亦系統性討論之。

4. Se/Cr/Mn/CO 系統之研究
以 [Se2Cr3(CO)10]2─ 為起始物與 Mn(CO)5Br 於丙酮溶液中反應，可得到兩個史無前例含硒混合鉻錳之化合物 [Et4N][Me2CSe2{Mn(CO)4}{Cr(CO)5}2] 與 [Et4N]2[Se2Mn3(CO)10{Cr(CO)5}2]。化合物 [Me2CSe2{Mn(CO)4}{Cr(CO)5}2]─ 的形成推測是經由丙酮之 C=O 鍵活化產生，而此化合物更容易由 [Se2Cr3(CO)10]2─ 與 Mn(CO)5Br 於丙酮溶液中進行酸化反應獲得。化合物 [Se2Mn3(CO)10{Cr(CO)5}2]2─ 亦能藉由化合物 [Me2CSe2{Mn(CO)4}{Cr(CO)5}2]─ 加入 Mn2(CO)10於 KOH 鹼性甲醇溶液中反應生成。然而，[Me2CSe2{Mn(CO)4}{Cr(CO)5}2]─ 或 [Se2Mn3(CO)10{Cr(CO)5}2]2─ 與 Mn(CO)5Br 於丙酮溶液中反應，皆會形成已知產物 [Se2Mn3(CO)9]─ 與 [Cr(CO)5Br]─。奇數電子之團簇物 [Se2Mn3(CO)10{Cr(CO)5}2]2─ 可透過加熱並通入CO氣體，穩定地轉變成順磁性49個電子之物種 [Se2Mn3(CO)9]2─。此外，化合物之生成及相關性質藉由理論計算進一步驗證。

5. S/Fe/CO 系統之研究
將 [SFe3(CO)9]2─ 與 BrCH2C(O)OCH3於 MeCN 溶液中反應，可得含酯基化合物 [Et4N][SFe3(CO)8(?-CO)(CH2C(O)OCH3)]。當 [SFe3(CO)9]2─ 與雙鹵試劑 X(CH2)nX' (X = Cl, X' = Br, n = 3; X = X' = I, n = 4) 於 MeCN 溶液中反應，可分別得到單取代產物 [Et4N][SFe3(CO)9(CH2)nX] (X = Cl, n = 3; X = I, n = 4)。將 [SFe3(CO)9]2─ 與 Hg(OAc)2 於丙酮溶液中反應，能單離出以 Hg 為橋基之產物 [Et4N]2[{SFe3(CO)9}2Hg]。相同條件下，若將 [SFe3(CO)9]2─ 與 HgI2 於丙酮溶液中反應，則生成以 HgI 為橋基之產物 [Et4N][SFe3(CO)9(?-HgI)]。此外，化合物 [{SFe3(CO)9}2Hg]2─ 亦可與 I(CH2)4I 於 MeCN 溶液中反應轉變成化合物[SFe3(CO)9(CH2)4I]─。反之，化合物 [SFe3(CO)9(CH2)4I]─ 亦能與 Hg(OAc)2 於丙酮溶液中反應轉變回化合物 [{SFe3(CO)9}2Hg]2─。此系列反應與化合物的生成及性質藉由理論計算加以驗證。

關鍵字

羰基團簇化合物

並列摘要

Abstract
1. Pb/Cr/CO System
The novel complex [Et4N]2[{PbCr2(CO)10}2(?-OH)2] was synthesized from the reaction of PbCl2 and Cr(CO)6 followed by metathesis with [Et4N]Br in KOH/MeOH solution. A CO2 molecule can insert itself into dianion [{PbCr2(CO)10}2(?-OH)2]2─ to form two new carbonate complexes, [Et4N]2[{PbCr2(CO)10}(CO3)] and [Et4N]2[{PbCr2(CO)10}2(CO3)], depending on the reaction conditions. [{PbCr2(CO)10}(CO3)]2─ and [{PbCr2(CO)10}2(CO3)]2─ can be converted back the hydroxo complex [{PbCr2(CO)10}2(?-OH)2]2─ under appropriate conditions. Its reactivity and formation are also investigated and discussed on the basis of DFT calculations.

2. Pb/Cr/M/CO (M = Fe, Ru) System
The new complex [Bu4N]2[Pb{Cr(CO)5}{Fe(CO)4}2] can be synthesized from the reaction of PbCl2, Cr(CO)6, and Fe(CO)5 followed by metathesis with [Bu4N]Br in a KOH/MeOH solution. The isostructural lead-chromium complex [Pb{Cr(CO)5}3]2─ can be synthesized under similar conditions. [Pb{Cr(CO)5}3]2─ can react with Mn(CO)5Br to form the Cr(CO)4-bridged dimeric lead-chromium carbonyl complex [Et4N]2[Pb2Br2Cr4(CO)18] which can further react with Mn(CO)5Br to give the known complex [PbBr2Cr2(CO)10]2─. On the contrary, the reaction of the trigonal-planar complexes [Pb{Fe(CO)4}3]2─ and [Pb{Cr(CO)5}{Fe(CO)4}2]2─ with Mn(CO)5Br can lead to the formation of the Fe3Pb2-trigonal bipyramidal complexes [Et4N]2[Fe3(CO)9{PbFe(CO)4}2] and [Et4N]2[Fe3(CO)9{PbCr(CO)5}2], respectively. Further, the Ru3Pb2-trigonal bipyramidal cluster [Et4N]2[Ru3(CO)9{PbCr(CO)5}2] can only be obtained directly from the reaction of PbCl2, Cr(CO)6, and Ru3(CO)12 in the presence of [Et4N]Br in a KOH/MeOH solution. Their reactivity, formation, and electrochemical redox reactions are also investigated and discussed on the basis of DFT calculations.

3. Se/M/CO (M = Cr, Mo, W) System
The selenium-capped trimolybdenum cluster compound [Et4N]2[Se2Mo3(CO)10] can be obtained from the reaction of the trichromium cluster compound [Se2Cr3(CO)10]2─ with 4 equiv of Mo(CO)6 in refluxing acetone. On the other hand, when [Se2Cr3(CO)10]2─ reacted with 4 equiv of W(CO)6 in refluxing acetone, the planar cluster compound [Et4N]2[Se2W4(CO)18] was isolated, which could further transform to the tritungsten cluster compound [Et4N]2[Se2W3(CO)10] in good yields. Alternatively, clusters [Se2Mo3(CO)10]2─ and [Se2W3(CO)10]2─ could be formed from the reactions of the monosubstituted products [Et4N]2[Se2Cr2M(CO)10] (M = Mo, W) with 3 equiv of M(CO)6 in acetone, respectively. The formation and structural features of the resultant homonuclear or the related heteronuclear clusters are discussed in terms of the effect of group 6 metals.
4. Se/Cr/Mn/CO System
We have discovered two unprecedented manganese-incorporated selenium-chromium carbonyl complexes [Et4N][Me2CSe2{Mn(CO)4}{Cr(CO)5}2] and [Et4N]2[Se2Mn3(CO)10{Cr(CO)5}2] from the reaction of [Et4N]2[Se2Cr3(CO)10] with Mn(CO)5Br in acetone. The formation of complex [Me2CSe2{Mn(CO)4}{Cr(CO)5}2]─, presumably via C=O activation of acetone, can be further facilitated by the acidification of the reaction of [Et4N]2[Se2Cr3(CO)10] with Mn(CO)5Br in acetone. Complex [Se2Mn3(CO)10{Cr(CO)5}2]2─ could also be obtained from the reaction of complex [Me2CSe2{Mn(CO)4}{Cr(CO)5}2]─ with Mn2(CO)10 in a KOH/MeOH/MeCN solution. However, treatment of [Me2CSe2{Mn(CO)4}{Cr(CO)5}2]─ or [Se2Mn3(CO)10{Cr(CO)5}2]2─ with Mn(CO)5Br in acetone led to the formation of the known complexes [Se2Mn3(CO)9]─ and [Cr(CO)5Br]─. Upon heating and bubbled with CO, the 51-electron cluster [Se2Mn3(CO)10{Cr(CO)5}2]2─ can readily convert to the paramagnetic 49-electron species [Se2Mn3(CO)9]2─. In addition, the nature and formation of [Me2CSe2{Mn(CO)4}- {Cr(CO)5}2]─ and [Se2Mn3(CO)10{Cr(CO)5}2]2─ were further examined by molecular orbital calculations at the B3LYP level of the density functional theory.

5. S/Fe/CO System
When [SFe3(CO)9]2─ was treated with BrCH2C(O)OCH3 in MeCN, the ester-functionalized complex [Et4N][SFe3(CO)8(?-CO)(CH2C(O)OCH3)] was obtained. When [SFe3(CO)9]2─ was treated with dihaloalkanes X(CH2)nX' (X = Cl, X' = Br, n = 3; X = X' = I, n = 4) in MeCN, the sulfur-alkylated complexes [Et4N][SFe3(CO)9(CH2)nX] (X = Cl, n = 3; X = I, n = 4) were formed, respectively. The Hg-bridged complex [Et4N]2[{SFe3(CO)9}2Hg] could be isolated from the reaction [SFe3(CO)9]2─ with Hg(OAc)2 in acetone. If [SFe3(CO)9]2─ was reacted with HgI2 under similar conditions, the HgI-bridged cluster [Et4N][SFe3(CO)9(?-HgI)] was produced. Moreover, complex [{SFe3(CO)9}2Hg]2─ can transform to [SFe3(CO)9(CH2)4I]─ upon the reaction with I(CH2)4I in MeCN. Conversely, [SFe3(CO)9(CH2)4I]─ can convert back to [{SFe3(CO)9}2Hg]2─ in the presence of Hg(OAc)2 in an acetone solution. The nature and formation of these complexes were also examined by molecular orbital calculations at the B3LYP level of the density functional theory.

參考文獻

(4) Adams, R. D.; Captain, B.; Fu, W.; Pellechia, P. J.; Smith, M. D. Angew. Chem., Int. Ed. Engl. 2002, 41, 1951.

(5) Adams, R. D.; Captain, B.; Zhu, L. J. Am. Chem. Soc. 2004, 126, 3042.

(6) Whitmire, K. H. Adv. Organomet. Chem. 1998, 42, 1.

(7) Riaz, U.; Cumow, O. J.; Curtis, M. D. J. Am. Chem. Soc. 1994, 116, 4357.

(8) Henderson, R. A. Chem. Rev. 2005, 105, 2365.