Deboronation and deprotonation of ortho-Carborane with N-heterocyclic carbenes.

Abstract

It is a matter of size: N-Heterocyclic carbenes can remove a proton from ortho-carborane to form a two-cage anion or attack the electropositive boron of ortho-carborane to yield a stable 1:2 carborane–carbene adduct. Which end product is formed depends on the steric bulk of the alkyl groups attached to the nitrogen atoms of the carbene.