Scope and mechanism of nitrile dihydroboration mediated by a β-diketiminate manganese hydride catalyst

Abstract

The manganese hydride dimer, [(^2,6-iPr₂PhBDI)Mn(μ-H)]₂, was found to mediate nitrile dihydroboration, rendering it the first manganese catalyst for this transformation. Stoichiometric experiments revealed that benzonitrile insertion affords [(^2,6-iPr₂PhBDI)Mn(μ-NCHC₆H₅)]₂ en route to N,N-diborylamine formation. Density functional theory calculations reveal the precise mechanism and demonstrate that catalysis is promoted by monomeric species.