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Synthesis, Structure, and Reactivity of Acid-Free Neutral Oxoborane
Hanqiang Wang1, Jie Zhang1, Jingting Yang1
1Department of Chemistry and State Key Laboratory of Synthetic Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China.
Abstract:
An efficient synthesis of an acid-free neutral oxoborane of the type carboranyl-B(carbene)=O has been developed via a serendipitous discovery from the reaction of 1,2-[BBr(carbene)]-o-carborane with AgOTf. This represents a new type of oxoborane. The stabilization of this oxoborane may be attributed to 1) kinetic stabilization provided by a bulky 3D carboranyl ligand and 2) thermodynamic stabilization offered by a carbene ligand. Crystallographic analyses support the presence of the shortest terminal B=O double bond ever reported thus far. Its reactivity has also been examined.
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