Haptophilicity and Substrate-Directed Reactivity in Diastereoselective Heterogeneous Hydrogenation
Haptophilicity and Substrate-Directed Reactivity in Diastereoselective Heterogeneous Hydrogenation
复制标题
DOI：
10.1021/acscatal.2c02028
复制
发表时间：
2022-06-13
期刊：
影响因子：
12.9
通讯作者：
Li，Christina W.
中科院分区：
文献类型：
--
作者：
Hong，Wei;Swann，William A.;Li，Christina W.
烯烃和芳烃的非均相氢化中的立体选择性通常由有机底物的空间性质决定，并且难以通过改变催化剂或实验参数来改变固有的空间偏好。获得反空间选择性的一种策略是将立体化学定义的官能团引入到基质中，其可以吸附到催化剂表面并从同一面“直接”氢加成。这一观点提供了一个多相定向氢化的概述，并阐明了几个设计规则的导向基团的身份，底物结构，和催化剂的组合物，导致非对映选择性反应。单组分非均相催化剂能够非对映选择性定向氢化，仅具有有限组的底物骨架和定向官能团。在一个给定的基板，导向基团的构象，空间体积，和吸附强度之间的复杂的相互作用，使得它难以预测空间或电子因素将主导的非对映选择性。然后，我们讨论了最近的例子，这个反应的催化剂，并期待对机会的催化剂结构，以产生更可调的和一般的多相定向加氢催化剂。
Stereoselectivity in heterogeneous hydrogenation of olefins and arenes is typically dictated by the steric properties of the organic substrate, and the inherent steric preference is difficult to alter through the modification of the catalyst or experimental parameters. One strategy to access counter-steric selectivity is to incorporate a stereochemically defined functional group into the substrate that can adsorb to the catalyst surface and “direct” hydrogen addition from the same face. This Perspective provides an overview of heterogeneous directed hydrogenation and elucidates a few design rules about directing group identity, substrate structure, and catalyst composition that lead to diastereoselective reactivity. Monometallic heterogeneous catalysts are capable of diastereoselective directed hydrogenation with only a limited set of substrate scaffolds and directing functional groups. In a given substrate, the complex interplay between directing group conformation, steric bulk, and adsorption strength makes it difficult to predict whether steric or electronic factors will dominate the diastereoselectivity. We then discuss more recent examples of bimetallic catalysts for this reaction and look toward opportunities for bimetallic structures to yield more tunable and general heterogeneous directed hydrogenation catalysts.