TY - JOUR
T1 - Accessing Chelating Extended Linker Bis(NHC) Palladium(II) Complexes
T2 - Sterically Triggered Divergent Reaction Pathways
AU - Wierenga, Tanita S.
AU - Vanston, Catriona R.
AU - Ariafard, Alireza
AU - Gardiner, Michael G.
AU - Ho, Curtis C.
N1 - Publisher Copyright:
© 2019 American Chemical Society.
PY - 2019/8/12
Y1 - 2019/8/12
N2 - We have demonstrated the profound effect that the N-substituent steric bulk of ethylene-linked bis(N-heterocyclic carbene) (bis(NHC)) species has on the mechanism of their formation via Pd(OAc)2-assisted deprotometalations. The binding mode of an ethylene-linked bis(NHC) ligand is chelating when it bears N-2,4-Me2C6H3 substituents but forms a mono(NHC) with a pendant imidazolium group for N-2,6-iPr2C6H3. An N-mesityl-substituted bis(NHC), with steric bulk intermediate between the two aforementioned substituents, generates a mixture of two chelating homoleptic normal/normal and heteroleptic normal/abnormal bis(NHC) complexes, as predicted by DFT calculations. Interestingly, the latter was seen to undergo facile reductive elimination, affording a novel tricyclic monodentate NHC ligand.
AB - We have demonstrated the profound effect that the N-substituent steric bulk of ethylene-linked bis(N-heterocyclic carbene) (bis(NHC)) species has on the mechanism of their formation via Pd(OAc)2-assisted deprotometalations. The binding mode of an ethylene-linked bis(NHC) ligand is chelating when it bears N-2,4-Me2C6H3 substituents but forms a mono(NHC) with a pendant imidazolium group for N-2,6-iPr2C6H3. An N-mesityl-substituted bis(NHC), with steric bulk intermediate between the two aforementioned substituents, generates a mixture of two chelating homoleptic normal/normal and heteroleptic normal/abnormal bis(NHC) complexes, as predicted by DFT calculations. Interestingly, the latter was seen to undergo facile reductive elimination, affording a novel tricyclic monodentate NHC ligand.
UR - http://www.scopus.com/inward/record.url?scp=85070561663&partnerID=8YFLogxK
U2 - 10.1021/acs.organomet.9b00356
DO - 10.1021/acs.organomet.9b00356
M3 - Article
AN - SCOPUS:85070561663
SN - 0276-7333
VL - 38
SP - 3032
EP - 3038
JO - Organometallics
JF - Organometallics
IS - 15
ER -