Enantioselective SN1-type reaction via electrochemically generated chiral α-Imino carbocation intermediate
Qifeng Lin1, Yingdong Duan1, Yao Li1
1Center of Basic Molecular Science, Department of Chemistry, Tsinghua University, Beijing, China.
Abstract:
Electrochemical reactions via carbocation intermediates remain fundamental transformations that build up molecular functionality and complexity in a sustainable manner. Enantioselective control of such processes is a great challenge in a highly ionic electrolyte solution. Here, we report an anodic generation of chiral α-imino carbocation intermediates by enamine catalysis. The chiral carbocation intermediates can be intercepted by a variety of nucleophiles such as alcohols, water and thiols with high stereoselectivity. The key SN1 step proceeds via a tertiary amine-mediated proton shuttle that facilitates facial selection in reacting with carbocation.
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