Normal and Abnormal Bonding of N-Heterocyclic Carbenes: Impact on Stability, Reactivity, and Catalysis
نویسنده
چکیده
N-heterocyclic carbenes (NHCs), typically derived from imidazolium salts, have provided highly powerful ligands for catalysis. Recently, abnormal C4 bonding rather than normal C2 bonding has been discovered as a new carbene bonding mode. We were interested in comparing the consequences of these two bonding modes on the metal center. Therefore we synthesized related palladium complexes 1 and 2 containing similarly cis chelating dicarbenes that bind via C2 and C4 respectively.
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