Dearomatization of Unactivated Arenes via Catalytic Hydroalkylation
Kelly A McDaniel1, Anna R Blood1, Gavin C Smith1
1Department of Chemistry and Winship Cancer Institute, Emory University, Atlanta, Georgia 30322, United States.
Abstract:
The dearomative cyclization of linear amides to complex spirocyclic butyrolactams has been enabled by photoredox catalysis through a reductive radical-polar crossover mechanism. This mechanism operates with precision on unactivated aromatic substrates to give a wide range of 1,4-hydroalkylation products. This method utilizes a simple organic catalyst/reductant pair to deliver products in a highly flexible manner with respect to substitution, and the products can be further functionalized under simple conditions to afford a collection of motifs. The mechanistic analysis performed here outlines the salient features of this strategy, which were applied to prepare a collection of complex scaffolds including the anticonvulsive agent gabapentin.
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