Carbocations can be categorized into classical carbenium ions and non-classical carbonium ions. These intermediates are ubiquitous in reactions of both fundamental and practical relevance, finding application in the petroleum industry as well as the discovery of new drugs and materials. Conveying stereochemical information to carbocations is therefore of interest to a range of chemical fields. While previous studies targeted systems proceeding through classical ions, enantiocontrol over their non-classical counterparts has remained unprecedented. Here we show that strong and confined chiral acids catalyse enantioselective reactions via the non-classical 2-norbornyl cation. This reactive intermediate is generated from structurally different precursors by leveraging the reactivity of various functional groups to ultimately deliver the same enantioenriched product. Our work demonstrates that tailored catalysts can act as suitable hosts for simple, non-functionalized carbocations via a network of non-covalent interactions. We anticipate that the methods described herein will provide catalytic accessibility to valuable carbocation systems.

碳正离子可分为经典碳正离子和非经典碳正离子。这些中间体在基础和实际相关的反应中无处不在，在石油工业以及新药物和材料的发现中得到应用。因此，将立体化学信息传递给碳正离子引起了一系列化学领域的兴趣。虽然之前的研究针对通过经典离子进行的系统，但对其非经典对应物的对映控制仍然是前所未有的。在这里，我们表明强和受限的手性酸通过非经典的 2-降冰片基阳离子催化对映选择性反应。这种反应性中间体是由结构不同的前体通过利用各种官能团的反应性最终提供相同的对映体富集产物而产生的。我们的工作表明，定制的催化剂可以通过非共价相互作用网络作为简单、非功能化碳正离子的合适宿主。我们预计本文描述的方法将为有价值的碳正离子系统提供催化可及性。