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Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
Isolation of an imino-N-heterocyclic carbene/germanium(0) adduct: a mesoionic germylene equivalent
Bochao Su1, Rakesh Ganguly, Yongxin Li
1Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Nanyang Link 21,Singapore 637371 (Singapore).
Abstract:
An autoionization of germanium dichloride/dioxane complex with an imino-N-heterocyclic carbene ligand (L) afforded a novel germyliumylidene ion, [(L)GeCl](+)[GeCl3](-), which was fully characterized. Reduction of the germyliumylidene ion with potassium graphite produced a cyclic species [(L)Ge], which can be viewed as both a Ge(0) species and a mesoionic germylene. X-ray diffraction analysis and computational studies revealed one of the lone pairs on the Ge atom is involved in the π system on the GeC2N2 five-membered ring. It was also confirmed that the nucleophilic behavior of [(L)Ge] as a two lone-pair donor.
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