Copper-Catalyzed Oxaziridine-Mediated Oxidation of C–H Bonds
作者:Hashim F. Motiwala、Belgin Gülgeze、Jeffrey Aubé
DOI:10.1021/jo3012336
日期:2012.8.17
bonds has been observed via copper-catalyzed reactions of oxaziridines. The oxidation proceeded with a variety of substrates, primarily comprising allylic and benzylic examples, as well as one example of an otherwise unactivated tertiary C–H bond. The mechanism of the reaction is proposed to involve single-electrontransfer to the oxaziridines to generate a copper-bound radicalanion, followed by hydrogen
Base-Mediated Cascade Rearrangements of Aryl-Substituted Diallyl Ethers
作者:Jolene P. Reid、Catherine A. McAdam、Adam J. S. Johnston、Matthew N. Grayson、Jonathan M. Goodman、Matthew J. Cook
DOI:10.1021/jo502403n
日期:2015.2.6
Two base-mediated cascade rearrangement reactions of diallyl ethers were developed leading to selective [2,3]-Wittig–oxy-Cope and isomerization–Claisen rearrangements. Both diaryl and arylsilyl-substituted 1,3-substituted propenyl substrates were examined, and each exhibits unique reactivity and different reaction pathways. Detailed mechanistic and computational analysis was conducted, which demonstrated
Catalytic Ketyl-Olefin Cyclizations Enabled by Proton-Coupled Electron Transfer
作者:Kyle T. Tarantino、Peng Liu、Robert R. Knowles
DOI:10.1021/ja404342j
日期:2013.7.10
Concerted proton-coupled electron transfer is a key mechanism of substrate activation in biological redox catalysis. However, its applications in organic synthesis remain largely unexplored. Herein, we report the development of a new catalytic protocol for ketyl-olefin coupling and present evidence to support concerted proton-coupled electron transfer being the operative mechanism of ketyl formation. Notably, reaction outcomes were correctly predicted by a simple thermodynamic formalism relating the oxidation potentials and pK(a) values of specific Bronsted acid/reductant combinations to their capacity to act jointly as a formal hydrogen atom donor.