Li-NHC complexes

Fehlhammer and coworkers [34] reported the synthesis of a homoleptic AThet-erocychc carbene-hthium complex by deprotonation of hydrotris(3-ethylimida-zohum)borate tetrafluoroborate with -butyllithium at -78 °C in diethyl ether, after loss of hthium tetrafluoroborate and -butane. X-ray quality crystals were obtained upon cooling. Interestingly, the two lithium atoms are complexed only by the NHC carbon atoms, whereas most other examples of Li-NHC complexes include some coordinated solvent. 

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