Synthesis, Structures, and Norbornene Polymerization Behavior of Neutral Nickel(II) and Palladium(II) Complexes Bearing Aryloxide Imidazolidin-2-imine Ligands

TY - JOUR

T1 - Synthesis, Structures, and Norbornene Polymerization Behavior of Neutral Nickel(II) and Palladium(II) Complexes Bearing Aryloxide Imidazolidin-2-imine Ligands

AU - Li, Mingyuan

AU - Shu, Xin

AU - Cai, Zhengguo

AU - Eisen, Moris S.

N1 - Publisher Copyright: © 2018 American Chemical Society.

PY - 2018/3/26

Y1 - 2018/3/26

N2 - A series of novel aryloxide imidazolidin-2-imine bidentate neutral Ni(II) and Pd(II) complexes bearing five- and six-membered chelate ring structures were synthesized and characterized. X-ray diffraction analysis results revealed that all of the Ni(II) complexes (Ni1-Ni3) and Pd(II) complexes (Pd1 and Pd3) adopted an almost square-planar geometry. In the presence of various cocatalysts such as MAO, MMAO, Et2AlCl, and EtAlCl2, all of the Ni(II) and Pd(II) complexes exhibited remarkably high activities (up to 2.6 × 107 g of PNB (mol of M)-1 h-1) toward the addition polymerization of norbornene. These catalyst systems produced high-molecular-weight polynorbornene (PNB) with narrow molecular weight distribution, except for the insoluble PNB obtained with Pd1-Pd3/MAO systems. The Pd(II) complexes showed particularly good thermostability with a high activity of 1.56 × 107 g of PNB (mol of Pd)-1 h-1 even at 80 °C. These complexes are rare examples of neutral Ni(II) and Pd(II) complexes bearing aryloxide-functionalized imidazolidin-2-imine ligands in the field of olefin polymerization.

AB - A series of novel aryloxide imidazolidin-2-imine bidentate neutral Ni(II) and Pd(II) complexes bearing five- and six-membered chelate ring structures were synthesized and characterized. X-ray diffraction analysis results revealed that all of the Ni(II) complexes (Ni1-Ni3) and Pd(II) complexes (Pd1 and Pd3) adopted an almost square-planar geometry. In the presence of various cocatalysts such as MAO, MMAO, Et2AlCl, and EtAlCl2, all of the Ni(II) and Pd(II) complexes exhibited remarkably high activities (up to 2.6 × 107 g of PNB (mol of M)-1 h-1) toward the addition polymerization of norbornene. These catalyst systems produced high-molecular-weight polynorbornene (PNB) with narrow molecular weight distribution, except for the insoluble PNB obtained with Pd1-Pd3/MAO systems. The Pd(II) complexes showed particularly good thermostability with a high activity of 1.56 × 107 g of PNB (mol of Pd)-1 h-1 even at 80 °C. These complexes are rare examples of neutral Ni(II) and Pd(II) complexes bearing aryloxide-functionalized imidazolidin-2-imine ligands in the field of olefin polymerization.

UR - http://www.scopus.com/inward/record.url?scp=85045244020&partnerID=8YFLogxK

U2 - 10.1021/acs.organomet.8b00059

DO - 10.1021/acs.organomet.8b00059

M3 - 文章

AN - SCOPUS:85045244020

SN - 0276-7333

VL - 37

SP - 1172

EP - 1180

JO - Organometallics

JF - Organometallics

IS - 7

ER -