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Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
Double C-H bond activation of acetylene by atomic boron in forming aromatic cyclic-HBC2BH in solid neon
Jiwen Jian1, Wei Li1, Xuan Wu1
1Department of Chemistry , Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials , Collaborative Innovation Center of Chemistry for Energy Materials , Fudan University , Shanghai 200433 , China .
Abstract:
The organo-boron species formed from the reactions of boron atoms with acetylene in solid neon are investigated using matrix isolation infrared spectroscopy with isotopic substitutions as well as quantum chemical calculations. Besides the previously reported single C-H bond activation species, a cyclic-HBC2BH diboron species is formed via double C-H bond activation of acetylene. It is characterized to have a closed-shell singlet ground state with planar D2h symmetry. Bonding analysis indicates that it is a doubly aromatic species involving two delocalized σ electrons and two delocalized π electrons. This finding reveals the very first example of double C-H bond activation of acetylene in forming new organo-boron compounds.
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