Phosphine-Promoted Ring Opening/Recyclization of Cyclopropyl Ketones to Access Hydrofluorenones
Jay Prakash Maurya1, S S V Ramasastry1
1Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Sector 81, S A S Nagar, Manauli, Punjab 140 306, India.
Abstract:
The ring-reorganizing transformations of activated cyclopropanes are typically achieved under acidic conditions. This Letter describes the first acid-free and Lewis base-mediated cascade ring opening/recyclization of designed cyclopropyl ketones to access tetrahydrofluorenones. We rationally merged the nucleophilic features of phosphines with the electronically biased cyclopropanes to synthesize several new classes of hydrofluorenones. We have also demonstrated the synthetic utility of the products in accessing highly functionalized molecular scaffolds.
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