Exploring novel bicyclic bridgehead phosphorus ligands for stereo- and regioselective palladium and copper catalysis

Abstract

The Briphos ligand, a bicyclic bridgehead phosphoramidite, possesses a strong π-acceptor ability due to its geometrical constraint. Briphos has found applications in diverse transition metal catalysis, exercising control over the electronic properties of metal catalysts through ligand-metal coordination. Within this dissertation, the exploration of the Briphos ligand encompasses an understanding of its properties, pioneering the development of novel atalytic reactivity in catalysis through the creation of innovative Briphos ligands, and conducting experimental and computational analyses of the ligand’s intricate reaction mechanism. The significant findings include: (i) Facilitating the transmetalation step via Briphos ligand utilization and its application in reductive crosscoupling. (ii) Designing a novel hemilabile Briphos ligand with potent steric effects for application in Pd-catalyzed hydrosilylation. (iii) Control of Cu-catalyzed hydropyridylation of conjugated dienes using bidentate ligands, coupled with an investigation into the reaction mechanism. (iv) Understanding the control of allylic substitution through the Briphos-structured bidentate phosphorus ligand and its impact on stereoselectivity. This research underscores the diverse utility and importance of the Briphos ligand in advancing catalytic methodologies and elucidating its multifaceted roles and applications.