Enantioselective Narasaka-Heck cyclizations: synthesis of tetrasubstituted nitrogen-bearing stereocenters.

ABSTRACT: The first examples of highly enantioselective Narasaka-Heck cyclizations are described. A SPINOL-derived P,N-ligand system enables Pd-catalyzed 5-exo cyclization of a range of oxime esters with sterically diverse trisubstituted alkenes to generate dihydropyrroles containing tetrasubstituted nitrogen-bearing stereocenters in 56 to 86% yield and 90?:?10 to 95?:?5 e.r. These processes are rare examples of reactions that proceed via enantioselective migratory insertion of alkenes into Pd-N bonds, and the first where trisubstituted alkenes are used to generate tetrasubstituted stereocenters with high enantioselectivity.

SUBMITTER: Race NJ 

PROVIDER: S-EPMC5390761 | biostudies-literature | 2017 Mar

REPOSITORIES: biostudies-literature