A Stereospecific, Intermolecular Biaryl-Coupling Approach to Korupensamine A En Route to the Michellamines

By what means and how well can axial chirality be controlled in an intermolecular Suzuki biaryl cross-coupling reaction? The directionality of reductive elimination [Eq. (1)] is completely controlled by using a strategically positioned internal ligand L to afford a single biaryl atropisomer corresponding to the korupensamine A skeleton. TIPS=iPr₃Si, Ts=H₃CC₆H₄SO₂.