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Updated: Feb 16, 2026

Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
Biradicaloid and Zwitterion Reactivity of Dicarbondiphosphide Stabilized with N-Heterocyclic Carbenes
Zhongshu Li1, Yuanfeng Hou1, Yaqi Li1
1Lehn Institute of Functional Materials (LIFM), School of Chemistry, Sun Yat-Sen University, 510275, Guangzhou, P. R. China.
Abstract:
Organic biradicals are usually very short lived species under standard laboratory conditions, which makes their experimental studies difficult. In contrast, heteroatom-substituted analogues of these biradicals show enhanced stability due to π-electron delocalization, which is why main group biradicals (or biradicaloids) of archetypical heterocyclobutanediyls have been thoroughly investigated. Herein, N-heterocyclic carbene (NHC)-stabilized dicarbondiphosphide compounds of the type (L2 )C2 P2 (L=NHC) were utilized to activate both single and multiple bonds in small molecules with a feasible concerted mechanism. This reactivity is explicable by considerable biradicaloid character of the dicarbondiphosphide compounds, which is further corroborated by theoretical studies. Furthermore, the dicarbondiphosphide compounds also exhibited Lewis base properties towards Lewis acids, such as borane and metal halides.
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