768-03-6 Facile Synthesis of Polysubstituted 2-Pyrones via TfOH-Mediated Ring Expansion of 2-Acylcyclopropane-1-carboxylates

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A facile route to polysubstituted 2-pyrones from readily available 2-acylcyclopropane-1-aryl-1-carboxylates mediated by TfOH is reported. The strongly donating 1-aryl group is important for directing the C-C bond cleavage of the donor-acceptor cyclopropane ring, which then leads to the formation of the 2-pyrone ring through lactonization. https://www.lookchem.com/CASDataBase_768-03-6.htm

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