Supported ionic liquid phase (SILP) catalysis

近年来，离子液体作为过渡金属均相催化的替代反应介质引起了人们极大的关注。除了非挥发性的工程优势外，许多研究小组已经证明了开发新的液-液两相反应体系的巨大潜力。然而，在某些情况下，当化学动力学很快时，反应可能发生在离子液体的表面或扩散层，而不是在主体溶剂中。因此，在这些情况下，普通的液-液两相催化可能不是实现具有离子催化层的催化反应的理想方式，因为只有一小部分相对昂贵的离子液体和溶解在其中的催化剂被有效地用于反应。在这个项目中，将研究一种含有活性过渡金属催化剂的中性、弱配位离子液体在多孔载体表面的固定化。当过渡金属催化剂通过溶解的配体配位时，离子液体通过物理吸附分布在载体上。这一概念将在至少两个连续的气相过程中进行评估：Rh催化的烯烃氢甲酰化和Ni催化的乙烯齐聚。对于这两个反应，我们将比较新型“负载型离子液体(SILP)催化剂”的催化性能与液-液两相催化的结果。对载体和模型体系上的活性催化物种进行详细的光谱研究将是我们了解活性、选择性和寿命差异的研究的组成部分。拟议的项目旨在以一种新的、令人兴奋的方式创建改进的催化系统，以弥合均相催化和多相催化之间的传统差距。参与的两个小组将把他们的互补专业知识带到联合项目中：Erlangen小组以其使用离子液体的均相催化方面的专业知识而闻名，而哥本哈根小组在连续支撑液体(SLP)和多相催化以及用光谱方法表征催化剂方面拥有长期的经验。这两个小组之间的合作创造了一种科学协同，在这一多学科领域的创新和高效研究方面具有巨大的潜力。

In the last years, ionic liquids have attracted significant attention as an alternative reaction medium for transition metal homogeneous catalysis. Besides the engineering advantage of their non-volatile nature, the great potential to develop new liquid-liquid biphasic reaction systems has been demonstrated by many research groups. However, in some cases when the chemical kinetics are fast the reaction may take place at the surface or in the diffusion layer of the ionic liquid rather than in the bulk solvent. In these cases, the ordinary liquid-liquid biphasic catalysis may therefore not be the ideal way to realise a catalytic reaction with an ionic catalyst layer, since only a minor part of the - relatively expensive - ionic liquid and of the catalyst dissolved therein is effectively used in the reaction. In this project, the immobilisation of a thin layer of a neutral, weakly-coordinating ionic liquid containing an active transition metal catalyst on the surface of a porous support will be investigated. While the transition metal catalyst is coordinated by dissolved ligands, the ionic liquid is distributed by physisorption on the support. This concept will be evaluated for at least two continuous gas phase processes: The Rh-catalysed hydroformylation of olefins and the Ni-catalyzed oligomerization of ethylene. For both reactions the catalytic performance of the new "supported ionic liquid phase (SILP) catalysts" will be compared to results for liquid-liquid biphasic catalysis. Detailed spectroscopic investigations of the active catalytic species on the support and in model systems will be an integral part of our studies to understand differences in activity, selectivity and lifetime. The proposed project aims to create improved catalytic systems in bridging the traditional gap between homogeneous and heterogeneous catalysis in a new, exciting manner. Both groups involved will bring their complementary expertise into the joint project: The Erlangen group is well-known for its expertise in homogeneous catalysis using ionic liquids, while the Copenhagen group has a long experience in continuous supported liquid phase (SLP) and heterogeneous catalysis and catalyst characterization by spectroscopic methods. The collaboration between the groups creates a scientific synergy with a great potential for innovative and efficient research in this multidisciplinary field.