Nickel-Catalyzed Annulations of ortho-Haloarylimines.

We report the discovery, development, and mechanism of a nickel-catalyzed annulation reaction between o-haloarylimines and electron-poor olefins. The reaction produces two adjacent anti stereocenters and a free secondary amine. Spirocycles are formed from cyclic imines. We characterized the key oxidative addition intermediate and identified a major path leading to competing homocoupling products. The activation energy of oxidative addition and the rate of oxidative addition complex isomerization were determined. The sensitivity of the reaction to reaction conditions was established in a quantitative manner and both the scope and limitations of the method are presented.