Download Nugget

Investigation of the Lewis Acidic Properties of N-Heterocyclic Carbene
Ligands and Their Implications for Catalysis
Colin D. Abernethy, Department of Chemistry, Keene State College
Keene, NH 03435
Cyclopentadienyl complexes of vanadium chlorides, which also contain N-heterocyclic
carbene (NHC) ligands have been prepared:
V
Cl
C
V
Cl
N
Cl
N
N V
C
N
Cl
N
(1)
C
N
N
(2)
(3)
In the low-valent complexes (1 and 2) no Cl···Ccarbene interligand interactions are
observed. However, in the vanadium(V) complex (3) there is a very short Cl···Ccarbene
distance. These findings suggest that coordination to a high-oxidation-state metal
center is required to induce Lewis acidic character in N-heterocyclic carbene ligands.