Organic synthesis using homogeneous and heterogeneous transition metal catalysts

过渡金属催化剂，如由铑、铂和钯组成的催化剂，用于各种工艺，包括汽车的催化转化器。这些相同的金属经常被用作分子催化剂，用于将简单的有机分子转化为更复杂的有机分子。分子态的金属催化剂是通过在金属上引入防止分解为体金属的配体来制备的。这些配体甚至可以使钯这样的金属溶于有机溶剂。配体还用于调节金属的反应性。手性配体甚至可以用于从非手性起始材料生成手性产物。这是合成手性产物最有效的方法之一，因为只需要初始手性物质（手性配体）的催化量。我们提出研究铃木偶联反应中三个重要的催化过程：烯烃的硼氢化、醇的氧化和碳-碳键的制备。我们对这些反应的研究将集中在以下几个关键点：了解反应机理；扩大反应范围；引入手性;回收催化剂。后一点经常被忽视，因为金属催化剂通常比它们用来生产的产品便宜。然而，它不仅能够更有效地回收催化剂，而且对产品的纯度也至关重要。这已经成为制药和电子材料行业的一个重大问题，在这些行业中，微量的金属会导致严重的问题。就医药产品而言，Pd和Rh等金属的存在可能导致严重的毒性。就材料而言，金属污染会导致电子设备短路，或限制材料作为绝缘体的能力。因此，我们还将讨论从反应混合物中去除金属的不同策略，以及固定配合物的方法，以便它们不会污染产品。

Transition metal catalysts such as those composed of rhodium, platinum and palladium are employed in a variety of processes, inculding catalytic converters in cars.  These same metals are often used in molecular catalysts for the conversion of simple organic molecules into more complex ones.  Metal catalysts in the molecular state are prepared by introducing ligands on the metal which prevent decomposition to the bulk metal.  These ligands can even make a metal like palladium soluble in organic solvents.  The ligands are also employed to adjust the reactivity of the metal.  Chiral ligands can even be used to generate chiral products from achiral starting materials.  This is one of the most efficient methods for the synthesis of chiral products, since only catalytic amounts of the initial chiral material (the chiral ligand) is required.  We have proposed to study three important catalytic processes, the hydroboration of olefins, the oxidation of alcohols and the preparation of carbon-carbon bonds in Suzuki coupling reactions.  Our study of these reactions will focus on the following key points:  understanding the mechanism; expanding the scope of the reaction; introducing chirality; recovering the catalyst.  This latter point is often overlooked since metal catalysts are usually cheaper than the products they are used to produce.  However, not only is it more efficient to be able to recover the catalyst, it is also critical for the purity of the product.  This has become a significant problem in both the pharmaceutical and electronic materials industries where trace amounts of metals can cause significant problems.  In the case of pharmaceutical products, the presence of metals such as Pd and Rh may cause significant toxicity.  In the case of materials, metal contamination can cause shorts in electronic devices, or limit the ability of a material to act as an insulator.  Thus we will also address different strategies to remove metals from reaction mixtures as well as ways to immobilize the complexes so that they do not contaminate the prodcut to begin with.