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Updated: Jul 8, 2026

Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions
Published on: July 30, 2017
Synthesis, structure and reactivity of a cationic bis(N-heterocyclic carbene) complex of thallium
Anthony R Leverett1, Thomas A Martin-Wells1, Joseph M Parr2
1School of Chemistry, UNSW Sydney, Kensington, NSW 2052, Australia. alasdair.mckay@monash.edu.
Abstract:
The cationic bis N-heterocyclic carbene (NHC) thallium species [Tl(IPr)2][Al{OC(CF3)3}4] (1) and [Tl(IMes)2][Al{OC(CF3)3}4] (2) (IPr = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene; IMes = 1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene) have been prepared. The solid-state structures of these species display considerable distortion of the NHC binding to thallium as a result of donation of electron-density from the metal s-type lone-pair orbital into the empty p-orbital of the carbenes. Attempts to utilise 1 and 2 as dual-purpose NHC transfer and halide abstractor compounds with Rh proved to be unsuccessful with the thallium being retained in Rh-Tl-Rh bridging products.
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