Bifunctional ligands that contain a Lewis base functionality may participate in metal-ligand cooperativity with first-row metals to form highly active catalysts. Most bifunctional pincer ligands contain strong-donor phosphine ligands, however, there have been recent interest in the use of more biomimetic ligand manifolds using <i>N,S</i>-donors. In the design of catalysts using non-traditional bifunctional ligands, judicious mechanistic studies are required to understand potential reaction pathways that may diverge from traditional mechanisms. Herein, we present detailed mechanistic studies of C=O and C=N hydroboration pathways using either mono- or divalent Mn complexes with bifunctional SNS ligands. While mechanisms operating by traditional outer-sphere “Noyori-type” 6-membered transition states are the more conventional and well-studied, they are not always the most energetically favored pathway. Instead, an inner-sphere bifunctional mechanism may present the most exergonic pathway. Experimental and computational insight into the details of these systems will be discussed.

Metal-ligand cooperativity in Mn-catalyzed hydroborations: Bifunctional [SNS] ligands lead to untraditional mechanism

ACS Spring Meeting 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.