Superelectrophilicity of 1,2-Azaborine: Formation of Xenon and Carbon Monoxide Adducts.

The BN analogue of ortho-benzyne, 1,2-azaborine, is shown to bind carbon monoxide and a xenon atom under matrix isolation conditions, demonstrating its strongly Lewis acidic superelectrophilic nature. The Lewis acid-base complexes involving CO and Xe can be cleaved photochemically and reformed by mildly annealing the matrices. The interaction energy of 1,2-azaborine with Xe is 3 kcal mol-1 according to quantum chemical computations, and is similar to that of the superelectrophilic carbene difluorovinylidene.