雙鉬五重鍵錯合物及其鎳-δ錯合物的反應性研究

Reactivity Studies of the Mo-Mo Quintuple Bonded Complex and its Nickel-δ Complex

莊馥戎(Fu-Jung Chuang)

指導教授 ： 蔡易州

國立清華大學/理學院/化學系/碩士(2014年)

摘要

本論文研究以高立體障礙的以雙氮基脒作為配基的雙鉬五重鍵錯合物Mo2[μ-κ2-HC(N-2,6-iPr2C6H3)2]2 (1)，利用其δ電子與第十族鎳金屬形成δ錯合物並進一步探討其反應性；另外，亦利用錯合物1低價數、低配位的特性將其與有機化合物小分子反應。錯合物1與Ni(PEt3)4和兩當量苯甲腈反應得到產物{μ-κ2-[κ2-NC(C6H4)-Ni(PEt3)2]}[μ-NC(H)Ph]Mo2[μ-κ2-HC(N-2,6-iPr2C6H3)2]2 (2)，其中一分子苯甲腈的氮原子鍵接至一鉬原子，該苯甲腈分子2號碳上有發生碳-氫鍵斷裂導致2號碳配位至一另一鉬原子上而形成一Mo2C3N六員環構型；同時氫原子轉移至第二分子苯甲腈腈基上的碳原子而形成苯亞胺基。錯合物1與Ni(PEt3)4和苯乙炔反應，得到碳-氫斷鍵且鎳原子與雙鉬金屬形成的δ錯合物[(PEt3)(η1-PhCC)Ni](μ-H){κ2-Mo2[μ-κ2-HC(N-2,6-iPr2C6H3)2]2} (3)；接著，將錯合物2與三甲基矽乙炔反應，得到具有亞乙烯基(Vinylidene)官能基的錯合物[μ-η1-PhC(H)C][μ-η1-TMSCC][μ-Ni(PEt3)](μ-H) {κ2-Mo2[μ-κ2-HC(N-2,6-iPr2C6H3)2]2} (4)；將錯合物2再與苯乙炔反應，得到兩分子苯乙炔於鎳原子和雙鉬金屬上以尾對尾的型式發生碳-碳耦合反應的錯合物[(η2-PhCCH)Ni(PEt3)][μ-η2:η1:η1-PhCC(H)C(H)C(Ph)]Mo2[μ-κ2-HC-(N-2,6-iPr2C6H3)2]2 (5)；將雙鉬四重鍵錯合物Mo2(μ-Cl)[(μ-Cl)2Li(OEt2)][μ-κ2-HC(N-2,6-iPr2C6H3)2]2與Pd(PEt3)3反應，得到一分子的三乙基膦與鉬原子鍵結的錯合物(η1-PEt3)(η1-Cl)(μ-Cl)Mo2[μ-κ2-HC(N-2,6-iPr2C6H3)2]2 (6)。此外，將錯合物 1與三甲基矽乙炔反應，形成具有芳香性的六員環雙鉬錯合物(μ-κ2-3,5-(Me3Si)2C4H2)Mo2[μ-κ2-HC(N-2,6-iPr2C6H3)2]2 (7)；錯合物1與腈類分子如苯甲腈反應，經由腈基團上的碳原子進行碳-碳耦合反應得到六員環燈籠型雙鉬錯合物[μ-κ2-NC(Ph)C(Ph)N]Mo2[μ-κ2-HC(N-2,6-iPr2C6H3)2]2 (8)；而1與立體阻礙較大的2,4,6-三甲基苯甲腈反應，可得到其以腈基團上氮原子配位至雙鉬金屬上的錯合物[η1-NC(Mes)]2Mo2[μ-κ2-HC(N-2,6-iPr2C6H3)(N-2-iPr-6-CH(κ1-CH2)CH3-C6H3)][μ-κ2-HC(N-2,6-iPr2C6H3)2] (9)。錯合物1與白磷分子反應則得到(μ-η4︰η4-P4){Mo2[μ-κ2-HC(N-2,6-iPr2C6H3)2]2}2 (10)，白磷分子從正四面體轉變成平面四方形的構型橋接於兩分子的1之間；錯合物1與苯甲酸乙酯反應，得到其苯環配位至鉬-鉬鍵上的錯合物(μ-η2-1,2︰η2-4,5-PhCOOEt)Mo2[μ-κ2-HC(N-2,6-iPr2C6H3)2]2 (11)；與富勒烯(C60)反應則得到其亦以其上的三個六員環配位至三分子之雙鉬五重鍵錯合物1，形成錯合物[[(μ:μ:μ-η2:η2:η2:η2:η2:η2-C60){Mo2[μ-κ2-HC(N-2,6-iPr2C6H3)2]2}3 (12)。

關鍵字

雙鉬五重鍵錯合物 ； δ錯合物

並列摘要

The quintuply-bonded dimolybdenum complex, Mo2[μ-κ2-HC(N-2,6-iPr2C6H3)2]2 (1), has a σ-bond, two π-bonds and two δ-bonds between two Mo atoms, so complex 1 can act as a supporting ligand to stabilize the group 10 metal atoms to form the δ-complexes, which show interesting reactivity toward organic compounds and small molecules. The reaction of 1 with Ni(PEt3)4 and two equiv of benzonitrile gives the complex, {μ-κ2-[κ2-NC(C6H4)-Ni(PEt3)2]}[μ-NC(H)Ph]Mo2[μ-κ2-HC(N-2,6-iPr2C6H3)2]2 (2). Complex 2 is formed via C-H bond cleavage of one molecule of benzonitrile. The reaction of 1 with Ni(PEt3)4 and phenylacetylene gives a δ-complex, [(PEt3)(η1-PhCC)Ni](μ-H){κ2-Mo2[μ-κ2-HC(N-2,6-iPr2C6H3)2]2} (3). In 3, 1 coordinates to the Ni(0) center by donation of its δ electrons, and the terminal C-H bond of phenylacetylene is cleaved and the resultant phenylacetylide and hydride coordinate to the Ni atom. Meanwhile, treatment of 2 with trimethylsilylacetylene affords a product containing a vinylidene group, [μ-η1-PhC(H)C][μ-η1-TMSCC][μ-Ni(PEt3)](μ-H){κ2-Mo2[μ-κ2-HC(N-2,6-iPr2C6H3)2]2} (4). Mixing 2 and two equivalents of phenylacetylene generates the complex, [η2-PhCCH][η1-Ni(PEt3)][μ-η2:η1:η1-PhCC(H)C(H)C(Ph)]Mo2[μ-κ2-HC-
(N-2,6-iPr2C6H3)2]2 (5), which is formed via a C-C coupling of two moleucles of PhCCH in a “tail-to-tail” mode.
The reaction of the quadruply-bonded dimolybdem complex, Mo2(μ-Cl)[(μ-Cl)2Li(OEt2)[μ-κ2-HC(N-2,6-iPr2C6H3)2]2 with Pd(PEt3)3 gives the complex, (η1-PEt3)(η1-Cl)(μ-Cl)Mo2[μ-κ2-HC(N-2,6-iPr2C6H3)2]2 (6). In addition, the addition of 1 with trimethylsilylacetylene affords the complex, (μ-κ2-3,5-(Me3Si)2C4H2)Mo2[μ-κ2-HC(N-2,6-iPr2C6H3)2]2 (7), which is resulted from the “head-to-tail” C-C coupling of two moleucles of Me3SiCCH. The reaction of 1 with benzonitrile gives the complex, [μ-κ2-NC(Ph)C(Ph)N]Mo2[μ-κ2-HC(N-2,6-iPr2C6H3)2]2 (8), which is formed via a C-C coupling of two moleucles of PhCN. On the other hand, treatment of 1 with two equiv of mesityl nitrile results in the isolation of the complex, [η1-NC(Mes)]2Mo2[μ-κ2-HC(N-2,6-iPr2C6H3)(N-2- iPr-6-CH(κ1-CH2)CH3-C6H3)][μ-κ2-HC(N-2,6-iPr2C6H3)2] (9), in which two mesityl nitrile groups terminally coordinate to Mo centers, mainly due to the steric effect. The reaction of 1 with white phosphorus leads to the isolation of the complex, (μ-η4︰η4-P4){Mo2[μ-κ2-HC(N-2,6-iPr2C6H3)2]2}2 (10), where the planar [P4]4- ligand bridges two fragments of 1. The reaction of 1 with ethyl benzoate generates the product, (μ-η2-1,2︰η2-4,5-PhCOOEt)Mo2[μ-κ2-HC(N-2,6-iPr2C6H3)2]2 (11), in which the phenyl group coordinates to two Mo centers in a face-on fashion. The reaction of 1 with [60]fullerene gives the complex, [(μ:μ:μ-η2:η2:η2:η2:η2:η2-C60]{Mo2[μ-κ2-HC(N-2,6-iPr2C6H3)2]2}3 (12), where three six-membered rings of the fullerene molecule coordinate to three moleucles of 1.

並列關鍵字

Mo-Mo Quintuple Bonded Complex ； δ Complex

參考文獻

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