Cooperative Activation of Small Molecules by Base-Stabilized Borylenes

Computational investigations were carried out using density functional theory (ωB97XD(toluene)/6-311+G*) on a series of base-stabilized borylenes to understand their ligand properties and potential toward the activation of enthalpically strong E-H bonds (E = H, NH₂, SiH₂Ph, and CH₃) as well as binding with small molecules such as CO and CNMe. The calculated reaction free energies and activation barriers suggest the ability of hitherto unexplored carbene-stabilized borylenes to not only split such bonds but also bind with CO and CNMe. A detailed mechanistic study of these bond activation processes reveals the noninnocent behavior of the carbene moiety attached to the boron center, thereby leading to cooperative splitting of the bonds of interest. The binding of CO and CNMe to the base-stabilized borylenes was investigated by energy decomposition analysis (EDA) with natural orbitals for chemical valence (NOCV), which gave appreciable interaction energy (ΔE_int) values, thereby indicating strong binding of CO and CNMe to these borylenes.