一系列钌的合成，表征和反应<em>Ñ</em> -triphos<sup>博士</sup>配合
Summary
钌膦配合物被广泛地用于均相催化反应，例如氢化反应。的一系列新的三齿钌配合轴承N个 -triphos配位体N（CH 2 PPH 2）3的合成的报道。另外，一个二氢化汝Ñ-triphos络合物与乙酰丙酸的化学计量反应进行说明。
Abstract
这里我们通过hydroxylmethylene膦前体与氨在氮气气氛下的磷基曼尼希反应在甲醇中报告一个三齿膦配位体N（CH 2 PPH 2）3（N- -triphos PH）（1）的合成。 N 个 -triphos 博士配体沉淀从溶液后约1小时回流，并可以分离，通过简单的过滤套管程序下，氮分析纯。在回流下N 个 -triphos 博士配体的[Ru 3（CO）12]的反应得到，显示CO气体对配体络合进化深红色溶液。复杂的[Ru（CO）2 {N（CH 2 PPH 2）3}-κ3 P]（2）中被隔绝在冷却至RT的橙色结晶。 31 P {1 1 H} NMR谱表明的特征单峰在较低频率相比于游离配体。的配合物2的甲苯溶液与氧气反应导致的碳酸盐配合物的[Ru（CO 3）（CO）{N（CH 2 PPH 2）3}-κ3 P〕瞬时沉淀（3），为空气稳定橙色固体。 3在15巴氢气在高压反应器中随后的氢化，得到二氢化物[期RuH 2（CO）{N（CH 2 PPH 2）3}-κ3 P]（4），将其充分利用X射线晶体学和核磁共振光谱。配合物3和4是潜在为一系列氢化反应，包括生物质衍生的产品，如乙酰丙酸（LA）的有用催化剂前体。配合物4被发现与干净的LA反应在质子源添加剂的存在的NH 4 PF 6，得到的[Ru（CO）{N（CH 2 PPH 2）3}-κ3 P {CH 3 CO（CH 2）2 CO 2 H}-κ2 O]（PF 6）（6）。
Introduction
钌膦基配合物是一些最广泛的研究和化学多功能分子催化剂。1-9典型地，这种钌催化剂包含决定了复杂的电子，空间相互作用，几何形状和溶解性或者单-或二齿配位体，并且其深刻地影响到催化活性。多齿膦系统已被广泛地少研究了催化，因为它们是公知的，由于多个磷供体在金属中心越大螯合效果与金属中心赋予更大的稳定性。这样的稳定可以是不希望的催化，然而，在更苛刻的反应条件下（较高的温度和压力下）这样的配体的配合物稳定性质可以是在确保催化剂完整性是有利的。我们10-12和13-18人已经调查传授复杂的稳定性和面部 COOR一个这样的多齿膦配体系统dination几何就是所谓 N- -triphos配体系列，其中3膦臂附着到心尖桥接氮原子形成一个潜在的三齿配体。其中一个主要的功能，以这些特定的配位体是容易的方式，它们可通过基于磷从容易得到的仲膦曼尼希反应（ 图1）来合成，因此，膦与各种R基团的，可以以高产率通常制备并以最少的工作了。这一方法的总的目标是提出一个浅显路线通过该钌配合物二氢化设有Ñ-triphos配体可用于随后的催化应用程序进行访问。最近，钌三磷酸基配合物已经引起注意，因为催化剂的衍生自生物质的产品，如乙酰丙酸，19,20生物酯11,21和二氧化碳22至更高的值的化学物质的氢化反应。将是有利展开属于任一，或比已报道，特别是如果它们是合成更容易访问，例如作为 N -triphos配位体的系统的更多活性钌三磷酸衍生物的范围。研究最多的碳为中心的模拟通常患有低产合成并涉及高度空气敏感金属磷化物的试剂，不同于N 个 -triphos配位体，这是更适应，更容易制备。10-18
Ñ-triphos配体保持相对不足的调查，只有钼，钨，钌，铑和金的复合物已报道从9出版物。与此形成鲜明对比的是硼碳为中心的类似物，为此，每年大约有50 900篇，分别以独特的化合物的大量。在亲手性烯烃23，我们在不对称催化加氢尽管如此，含有复合ñ-triphos发现应用程序LL的N作为不对称cyclohydroamination -protectedγ-丙二烯基磺酰胺。24此外，钌络合物由笨重Ñ-triphos配体具有磷杂配位部分的协调被认为激活硅烷，在有机硅化学的发展的关键步骤。25
由于在催化正在进行的研究项目的一部分，我们试图准备了一系列钌ñ-triphos 博士预催化剂，并研究它们的化学计量反应和催化潜力。尽管N 个 -triphos 博士最早被报道在25年前钼复合物，它们的应用，催化或以其他方式还没有被查处。这项工作表明N 个 -triphos支架，这尽管是普遍欠发达，拥有许多理想的特性，如复杂的稳定应用。在这里我们报告的合成路线和表征一系列钌Ñ-triphos 博士络合物可能会发现在催化氢化反应中的应用。
Protocol
Representative Results
Discussion
这里我们描述了高效的合成方法对于三齿膦配位体的合成和一系列钌配合物。 N 个 -triphos 博士配位体（1）可以高产率与一个简约的处理过程容易地制备。用于合成这些类型的配体的本磷基曼尼希反应是相当普遍的，并可以用于其它配位体的衍生物具有不同R基团上的P原子。10-12,15-18此外，这种合成方法是适合于在类似的碳为中心的三磷酸配位体，并且可以使用?…
Disclosures
The authors have nothing to disclose.
Acknowledgements
AP is grateful to Imperial College London for a PhD studentship via the Frankland Chair endowment. Johnson Matthey plc are also thanked for the loan of the precious metal salts used in this work.
Materials
| Methanol | – | – | Obtained from in-house solvent purification system: Innovative Technology, inc "pure solv" drying tower. Stored in ampules over activated molecular sieves under nitrogen. |
| Toluene | |||
| Diethyl Ether | |||
| Tetrahydrofuran (THF) | |||
| Acetonitrile | |||
| d6-Acetone | VWR | VWRC87152.0011 | Store in fridge |
| Triethylamine | Sigma-Aldrich | TO886-1L | Distilled and stored over activated molecular sieves under N2 |
| 2M Ammonia solution in methanol | Sigma-Aldrich | 341428-100ML | Solution comes in a "Sure-Seal" bottle |
| NH4PF6 | Sigma-Aldrich | 216593-5G | Store in desiccator |
| Levulinic Acid | Acros Organics | 125142500 | Solid but melts close to room temperature |
| 3 Å Molecular sieves | Alfa Aesar | LO5359 | Activate by heating over night under vacuum |
| Schlenk flasks | GPE | Custom design | – |
| Dual-manifold Schlenk line | GPE | Custom design | Dual-manifold of i) N2 that has been passed through a silica drying column and ii) vacuum. |
| Rotary vacuum pump | Edwards | RV3 A652-01-903 | – |
| 100 ml Autoclave Engineer's high pressure reactor | Autoclave Engineer | Custon design | – |
| Vortex Stirrer | VWR | 444-1378 | – |
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