Abstract
The development of novel strategies to disrupt symmetry at a molecular level is a longstanding pursuit within the organic chemistry community. Despite their importance in many biologicaly active molecules, the asymmetric construction of all-carbon quaternary centers and b-arylethylamines represent major challenges for synthetic chemists. Taking advantage of a cyclic intermediate to transfer chiral information, rearrangement reactions represent a potential solution to this problem. Inspired by the potential of radical Smiles rearrangements to meet the challenge of generating quaternary stereocenters, we sought to develop an asymmetric version of this transformation to provide enantioenriched acyclic amides bearing an a-all-carbon quaternary center. We hypothesized that the presence of a chiral linker conjugated to the N-phenyl methacrylamides could induce enantioselectivity in this process. The sulfinyl group in the starting material not only directs the [1,4]-migration of the aryl moiety onto the α-carbon of the amide, thus governing its absolute configuration, but also acts as a traceless chiral auxiliary.
Encouraged by our success in the first project, we sought to expand the applicability of this strategy in the aminoarylation of olefins with an enantioenriched arylsulfinylacetamide as a bifunctional reagent that would enable stereocontrolled synthesis of b-arylethylamine.
Hervieu, Cédric