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Updated: Nov 20, 2025

Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
Stabilization of a bismuth-bismuth double bond by anionic N-heterocyclic carbenes
Luong Phong Ho1, Matthias Tamm1
1Institut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Hagenring 30, 38106 Braunschweig, Germany. m.tamm@tu-bs.de.
Abstract:
The bismuth dichloride complex (WCA-IDipp)BiCl2, which bears an anionic N-heterocyclic carbene ligand with a weakly coordinating borate moiety (WCA-IDipp, WCA = B(C6F5)3, IDipp = 1,3-bis(2,6-diisopropylphenyl)imidazolin-2-ylidene), was prepared by salt metathesis reaction between BiCl3 and the lithium salt (WCA-IDipp)Li·toluene. Subsequent two-electron reduction with 1,4-bis(trimethylsilyl)-1,4-dihydropyrazine afforded the dibismuthene (WCA-IDipp)2Bi2, which displays a bismuth-bismuth double bond.
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