Stereocontrol in homogeneous catalytic hydrogenation via hydroxyl group coordination
Stereocontrol in homogeneous catalytic hydrogenation via hydroxyl group coordination
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DOI：
10.1021/ja00342a080
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发表时间：
1983-02
影响因子：
15
通讯作者：
G. Stork;D. Kahne
中科院分区：
文献类型：
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作者：
G. Stork;D. Kahne
催化氢化反应中立体化学的控制一直是一个理想但难以实现的目标。在许多情况下，除非有极其接近的类比，否则甚至无法预期立体化学结果。多年来，我们一直致力于寻找解决这种情况的方法，希望对预先存在的、易于引入的中心的某种形式的吸引力可能导致所需的立体化学控制。羟基通常在氢化反应以外的指导反应（过氧酸氧化、西蒙斯-史密斯环丙烷化等）中发挥着良好的作用，但只有零星的报道表明在氢化反应中存在这种类型的立体控制的可能性。无论如何，这些孤立的观察结果都没有为该问题带来普遍有用或可预测的解决方案。在使用 Wilkinson 铑催化剂进行了一些不成功的实验后，2 我们转向 Crabtree 等人引入的铱催化剂 Ir (cod) py (PCy3) PF63· 4。 5 因为它有两个可与双齿底物配位的位点，并且因为它减少三取代双键的能力使得对相当范围的结构类型的研究成为可能。关于醇会使这种催化剂失活的报道有些令人不安，但确实表明醇功能可能是一种非常有效的配体。
The control of stereochemistry in catalytic hydrogenation re-actions has been a desirable but elusive goal. In many instances, the stereochemical result cannot even be anticipated unless ex-tremely close analogy is available. We have been interested for a number of years in finding means to remedy thissituation in the hope that some form of attraction to a preexisting, easily introduced center might lead to the desired stereochemical control. The hydroxyl group has often served well in directing reactions other than hydrogenation (peroxy acid oxidations, Simmons-Smith cyclopropanation, etc.) but only scattered reports1 have appeared that suggest the possibility of this type of stereocontrol in a hydrogenation reaction. In any event, none of these isolated observations have led to a generally useful or predictable solution to the problem. After some unsuccessful experiments with Wilkinson’s rhodium catalyst, 2 we turned to the iridium catalyst Ir (cod) py (PCy3) PF63· 4 introduced by Crabtree et al. 5 because it has two sites that would be available for coordination with a bidentate substrate andbecause its ability to reduce trisubstituted double bonds made possible the study of a considerable range of structural types. The report6 that'alcohols deactivate this catalyst was somewhat disturbing but did suggest that the alcohol function might be a very effective ligand.