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Published on: February 7, 2019
Nucleophilic ring opening of cyclopropane hemimalonates using internal Brønsted acid activation
Michael R Emmett1, Michael A Kerr
1Department of Chemistry, The University of Western Ontario, London, Ontario, Canada N6A 5B7.
Abstract:
The reaction of cyclopropanes, geminally disubstituted with one carboalkoxy and one carbohydroxy group, undergoes ring-opening reactions with indole nucleophiles under catalyst-free, hyperbaric (13 kbar) conditions. An internal hydrogen bond is postulated as the mode of activation obviating the need for the Lewis acid catalyst normally used for such donor-acceptor cyclopropane chemistry. These conditions avoid decarboxylation and yield useful adducts with the carboxylic acid group intact for further elaboration.
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