A family of N-heterocyclic carbene-stabilized borenium ions for metal-free imine hydrogenation catalysis.

ABSTRACT: This manuscript probes the steric and electronic attributes that lead to "frustrated Lewis pair" (FLP)-type catalysis of imine hydrogenation by borenium ions. Hydride abstraction from (ItBu)HB(C₆F₅)₂2 prompts intramolecular C-H bond activation to give (CHN)₂(tBu) (CMe₂CH₂)CB(C₆F₅)₂3, defining an upper limit of Lewis acidity for FLP hydrogenation catalysis. A series of seven N-heterocyclic carbene-borane (NHC-borane) adducts ((R'CNR)₂C)(HBC₈H₁₄) (R' = H, R = dipp 4a, Mes 5a, Me 8a; R = Me R' = Me 9a, Cl, 10a) and ((HC)₂(NMe)(NR)C)(HBC₈H₁₄) (R = tBu, 6a,

SUBMITTER: Farrell JM 

PROVIDER: S-EPMC5810240 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature