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Updated: Oct 29, 2025

Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
Highly Electron-Deficient Dicyanomethylene-Functionalized Triarylboranes with Low-Lying LUMO and Strong Lewis Acidity
Guanming Liao1,2, Xing Chen1, Yali Qiao3
1Key Laboratory of Cluster Science, Ministry of Education of China, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 102488, P. R. China.
Abstract:
A series of dicyanomethylene-functionalized triarylboranes is reported in this work, with low-lying LUMO energy levels at ca. -3.66 eV for MesB-ACN. The single-crystal structures of the mono- and dianion of Mes*B-ACN were obtained via chemical reduction, which revealed a conversion from a quinoidal to an aromatic structure. The strong Lewis acidity of these compounds is reflected in a fluoride-anion binding experiment. This work introduces a facile strategy for modulating the electron deficiency of boron-containing compounds.
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