Mono- and di-phosphine oxide complexes of aluminium, gallium and indium with weakly coordinating triflate anions - Synthesis, structures and properties
Mono- and di-phosphine oxide complexes of aluminium, gallium and indium with weakly coordinating triflate anions - Synthesis, structures and properties
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铝、镓和铟与弱配位三氟甲磺酸根阴离子的单氧化膦和二氧化膦配合物 - 合成、结构和性能
DOI：
10.1016/j.poly.2021.115529
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发表时间：
2021
期刊：
影响因子：
2.6
通讯作者：
Cairns K
中科院分区：
文献类型：
--
作者：
Cairns K
第 13 族三氟甲磺酸酯 M(OTf)3(M = Al, Ga, In; OTf = CF3SO3−) 与 3 mol 的反应。等式R3PO（R = Ph 或 Me）的合成得到六配位络合物 [M(OTf)3(R3PO)3]，与配位三氟甲磺酸酯，为白色粉末状固体。同样，使用 3 mol。等式PyNO（吡啶-N-氧化物）很容易形成[In(OTf)3(PyNO)3]，其晶体结构证实了聚体八面体排列。相反，较硬的路易斯酸 Al(III) 和 Ga(III) 与 PyNO 的反应会产生混合物，最有可能是 3:1 和 4:1 物质，[M(OTf)3(PyNO)3] 和 [M(OTf)2(PyNO)4][OTf] (M = Al, Ga)。这两种四物质均已通过单晶 X 射线研究得到证实，并显示以反式异构体的形式存在。 Me3PO 与 In(OTf)3 配位的较高比例（4:1、5:1 和 6:1）也可以通过适当改变反应化学计量来实现，配位的 OTf 基团很容易被 Me3PO 取代。盐的两种多晶型物 [In(OTf)2(Me3PO)4][In{(OH2)2(OTf)4}(Me3PO)4] 的晶体结构，其中[In{(OH2)2(OTf)4}(Me3PO)4]−阴离子（通常）由“InIII(OH2)2(Me3PO)4”单元组成，其中四个 OTf 阴离子与水配体通过氢键键合，产生整体单阴离子电荷。 [In(OTf)2(Ph3PO)4][In{(OH2)4(OTf)4}(Ph3PO)2]中也存在类似的排列，其结构表明与[In{(OH2)4(OTf)4}(Ph3PO)2]-中的四个水配体相关的所有氢原子与OTf基团形成显着的氢键；具体来说，四个 OTf−阴离子各自显示出两个 O⋯H 相互作用，形成将赤道水配体连接成 24 元“伪大环”环的桥梁。还描述了单核 5:1 配合物 [Ga(Me3PO)5(MeCN)][OTf]3 的晶体结构。使用二氧化二膦 dppmO2(Ph2P(O)CH2P(O)Ph2) 与 M(OTf)3 以 3:1 的比例轻松提供所有三种金属的三螯合物物质 [M(dppmO2)3][OTf]3，同时2:1 的比例也给出 [Ga(OTf)2(dppmO2)2][OTf]。报告了 [Al(dppmO2)3][OTf]3·MeCN 和 [Ga(dppmO2)3][OTf]3·2CHCl3 的晶体结构。多核（1H,13C{1H},19F{1H},31P{1H},27Al,71Ga 和 115In，适当时）NMR 数据表明，在 CD3CN 中，配合物是不稳定的，不同的 R3PO 配位环境是没有区别（尽管配位和“游离”Me3PO 之间的交换在 31P NMR 时间尺度上很慢），而 MeCN 溶剂也取代了金属配位层中的 OTf。
Reaction of the Group 13 triflates, M(OTf)3(M = Al, Ga, In; OTf = CF3SO3−), with 3 mol. eq. of R3PO (R = Ph or Me) gives the six-coordinate complexes, [M(OTf)3(R3PO)3], with coordinated triflate, as white powdered solids. Similarly, using 3 mol. eq. of PyNO (pyridine-N-oxide) readily forms [In(OTf)3(PyNO)3], whose crystal structure confirms a mer octahedral arrangement. In contrast, reaction of the harder Lewis acids Al(III) and Ga(III) with PyNO produce mixtures, mostly likely of the 3:1 and 4:1 species, [M(OTf)3(PyNO)3] and [M(OTf)2(PyNO)4][OTf] (M = Al, Ga). Both of the tetrakis species have been confirmed via single crystal X-ray studies and shown to exist astransisomers. Higher ratios (4:1, 5:1 and 6:1) of Me3PO coordinated to In(OTf)3can also be achieved by varying the reaction stoichiometry appropriately, with the coordinated OTf groups readily displaced by the Me3PO.Crystal structures of two polymorphs of the salt, [In(OTf)2(Me3PO)4][In{(OH2)2(OTf)4}(Me3PO)4], in which the [In{(OH2)2(OTf)4}(Me3PO)4]−anion is (unusually) comprised of a ‘InIII(OH2)2(Me3PO)4′ unit with four OTf anions H-bonded to the aquo ligands, giving the overall monoanionic charge. A similar arrangement is present in [In(OTf)2(Ph3PO)4][In{(OH2)4(OTf)4}(Ph3PO)2], the structure of which shows that all of the H atoms associated with the four aquo ligands in the [In{(OH2)4(OTf)4}(Ph3PO)2]−form significant H-bonds to the OTf groups; specifically, the four OTf−anions each show two O⋯H interactions, forming bridges that link the equatorial aquo ligands into a 24-membered ‘pseudo-macrocyclic’ ring. The crystal structure of the mononuclear 5:1 complex, [Ga(Me3PO)5(MeCN)][OTf]3, is also described.Using the diphosphine dioxide, dppmO2(Ph2P(O)CH2P(O)Ph2), with M(OTf)3in a 3:1 ratio readily affords the tris-chelate species, [M(dppmO2)3][OTf]3for all three metals, while a 2:1 ratio also gives [Ga(OTf)2(dppmO2)2][OTf]. Crystal structures of both [Al(dppmO2)3][OTf]3·MeCN and [Ga(dppmO2)3][OTf]3·2CHCl3are reported.Multinuclear (1H,13C{1H},19F{1H},31P{1H},27Al,71Ga and115In, where appropriate) NMR data show that in CD3CN the complexes are labile and the different R3PO coordination environments are not distinguished (although exchange between coordinated and ‘free’ Me3PO is slow on the31P NMR timescale), while the MeCN solvent also replaces OTf in the metal coordination sphere.