Generations and Reactions of Reactive Organic Cations Using Flow Redox Systems

点击翻译按钮获取中文摘要

Recently we have developed the "cation pool" method, which involves generation of highly reactive carbocations by low temperature electrolysis followed by reactions with a variety of nucleophiles. Micro flow reactors have received significant interest in the stream of downsizing of chemistry, and they are expected to make an innovative and revolutionary change for chemical synthesis. The advantages of microflow reactors of easy modulation and the possibility of combining reactors are quite useful to construct flow type redox systems for the organic transformations. On the basis of this concept we have developed "cation flow" method using microflow electrochemical reactors, which involves generation of highly reactive carbocations by low temperature electrolysis. This method enables the manipulation of carbocation intermediates to achieve direct oxidative C-C bond formation. Based on the "cation flow" method, continuous sequential combinatorial synthesis can be accomplished by simple flow switching. As an extension of the "cation flow" method, an electrochemical paired micro flow system that involves concurrent anodic generation of carbocations and cathodic generation of carbon nucleophiles followed by their reactions to achieve straightforward C-C bond formation has been developed. Anodic methoxylation of several organic compounds have also been achieved in the absence of intentionally added supporting electrolyte using an electrochemical microflow system.