Palladium-catalyzed stereoselective ring-opening reaction of aryl cyclopropyl ketones

Abstract

Herein was reported that α,β-unsaturated ketones could be obtained by palladium-catalyzed ring-opening of mono-substituted cyclopropyl ketones efficiently and systematically. (E)-1-arylbut-2-en-1-ones were generated from aryl cyclopropyl ketones stereoselectively in yields of...

An Intermolecular Hydroarylation of Unactivated Arylcyclopropane via Re2O7/HFIP-Mediated Ring Opening

“…The introduction of both donor and acceptor substituents at vicinal positions, initially reported by Wenkert and Reissig in the 1970s, affording donor−acceptor (D−A) cyclopropanes, 3 leads to the significant enhancement of reactivity as a result of C−C bond polarization through a synergy between the donor and acceptor substituents. A large variety of transformations based on ring opening of D−A cyclopropanes have been realized ever since, 4 including cycloadditions, 5 1,3-difunctionalizations, 6 rearrangements, 7 homoconjugate addition with heteroatomic nucleophiles, 8 arylation with electron rich arenes 9 or heteroarenes, 10 etc. On the contrary, arylation of D−A cyclopropanes with unactivated arenes has been realized only recently by using TfOH (Figure 1a) 11 or via an electrochemically mediated process (Figure 1b), 12 and catalytic methods for ring opening of unactivated cyclopropanes are relatively scarce.…”