Intermolecular, Catalytic Asymmetric Hydroamination of Bicyclic Alkenes and Dienes in High Yield and Enantioselectivity.

Intermolecular, Catalytic  Asymmetric Hydroamination of Bicyclic Alkenes and Dienes in High Yield  and Enantioselectivity.

J. Am. Chem. Soc.  2008130,  12220-12221.

A set of catalytic, intermolecular hydroaminations of strained bicyclic olefins and dienes are reported that occur in both high yield and high enantioselectivity. These reactions occur with a catalyst generated from [Ir(cyclooctene)Cl]2, sterically hindered and electron-rich derivatives of the Segphos and BIPHEP family of ligands, and a soluble base. This system catalyzes the addition of various anilines to norbornene, norbornadiene, and other bicyclic olefins. The products from addition of p-anisidine can be transformed to BOC-protected norbornylamine and to substituted cyclopentanes in nearly enantiopure form. Mechanistic studies show that addition of aniline-d2 occurs in a syn fashion and suggest that the catalytic cycle comprises oxidative addition of aniline to form a bis-anilide hydride complex, followed by migratory insertion of olefin and reductive elimination of product in a series of steps involving iridium complexes containing ancillary bisphosphine and arylamide ligands. Read more on publisher's site.