TY - JOUR
T1 - Neutral and cationic methallyl nickel complexes in alkene activation
T2 - a combined DFT, ESI-MS and chemometric approach
AU - Trofymchuk, Oleksandra S.
AU - Ortega, Daniela E.
AU - Cortés-Arriagada, Diego
AU - Pereira, Alfredo
AU - Daniliuc, Constantin G.
AU - Klitzke, Clecio F.
AU - Santos, Leonardo S.
AU - Rojas, Rene S.
N1 - Publisher Copyright:
© The Royal Society of Chemistry 2021.
PY - 2021/11/21
Y1 - 2021/11/21
N2 - Herein, we report a comparative study of ethylene activation and 1-hexene isomerization carried out with isomeric neutral and cationic methallyl nickel complexes L1Ni(η3-C3H5) and [L1Ni(η3-C3H5)][B(ArF)4] in the presence of borane co-catalysts. To understand the reactivity of the nickel complexes withNacNac ligands, we used chemometric methods to classify different catalysts reported to date. The mechanism of the interaction of [L1Ni(η3-C3H5)][B(ArF)4]/B(C6F5)3with 1-hexene was studied by ESI-MS which allowed the detection of cationic species formedin situ. Moreover, there is a very small difference in reactivities from combination of nickel complexes and borane co-catalysts used for alkene isomerization, while the reactivity with ethylene of both systems is very different; [L1Ni(η3-C3H5)][B(ArF)4]/B(C6F5)3produces butene, while L1Ni(η3-C3H5)/B(C6F5)3forms polyethylene. Furthermore, DFT studies revealed that the origin of the catalytic activity in the cationic and neutral methallyl nickel complexes co-activated by B(C6F5)3is mainly from direct steric effects of the ligand-nickel center where the conformation of the chelate ring is affected by the catalyst symmetry. This work demonstrates how the cationic or neutral nature of the same system affects its catalytic and structural properties.
AB - Herein, we report a comparative study of ethylene activation and 1-hexene isomerization carried out with isomeric neutral and cationic methallyl nickel complexes L1Ni(η3-C3H5) and [L1Ni(η3-C3H5)][B(ArF)4] in the presence of borane co-catalysts. To understand the reactivity of the nickel complexes withNacNac ligands, we used chemometric methods to classify different catalysts reported to date. The mechanism of the interaction of [L1Ni(η3-C3H5)][B(ArF)4]/B(C6F5)3with 1-hexene was studied by ESI-MS which allowed the detection of cationic species formedin situ. Moreover, there is a very small difference in reactivities from combination of nickel complexes and borane co-catalysts used for alkene isomerization, while the reactivity with ethylene of both systems is very different; [L1Ni(η3-C3H5)][B(ArF)4]/B(C6F5)3produces butene, while L1Ni(η3-C3H5)/B(C6F5)3forms polyethylene. Furthermore, DFT studies revealed that the origin of the catalytic activity in the cationic and neutral methallyl nickel complexes co-activated by B(C6F5)3is mainly from direct steric effects of the ligand-nickel center where the conformation of the chelate ring is affected by the catalyst symmetry. This work demonstrates how the cationic or neutral nature of the same system affects its catalytic and structural properties.
UR - http://www.scopus.com/inward/record.url?scp=85119370947&partnerID=8YFLogxK
U2 - 10.1039/d1cy01595h
DO - 10.1039/d1cy01595h
M3 - Article
AN - SCOPUS:85119370947
SN - 2044-4753
VL - 11
SP - 7475
EP - 7485
JO - Catalysis Science and Technology
JF - Catalysis Science and Technology
IS - 22
ER -