Heterolytic Dihydrogen Activation by a Frustrated Carbene–Borane Lewis Pair

Abstract

Relief from frustration: The sterically demanding carbene 1,3-di-tert-butylimidazolin-2-ylidene and B(C6F5)3, a “frustrated” Lewis pair, is a viable system for the activation of CO, HH, and CH bonds. However, slow rearrangement to an abnormal carbene–borane adduct allows the irreversible formation of a strong BC bond and enables this system to circumvent frustration at the expense of its activity.