TY - JOUR
T1 - Synthesis of Titanium Heteroarylphosphinimine Complexes and Application for Ethylene Polymerization
AU - Wang, Tieshi
AU - Chen, Jianjun
AU - Ye, Lin
AU - Zhang, Aiying
AU - Feng, Zengguo
N1 - Publisher Copyright:
© 2018 Chinese Chemical Society & SIOC, CAS.
PY - 2018/8/1
Y1 - 2018/8/1
N2 - Mono-and bisdiphenyl substituted heteroarylphosphines R-PPh2[R=2-pyridyl (3a), 2-thienyl (3b) and 2-furyl (3c)] and Ph2P-R'-PPh2[R'=2,6-pyridyl (6a), 2,5-thienyl (6b) and 2,5-furyl (6c)] were synthesized. After Staudinger reaction with Me3SiN3, those heteroarylphosphines were converted into the heteroarylphosphinimine ligands, R-PPh2(NSiMe3) and (Me3SiN)Ph2P-R"-PPh2(NSiMe3). The subsequently dehalosilylation reaction with CpTiCl3 afforded the corresponding Ti heteroarylphosphinimine halfmetallocenes as olefin polymerization catalysts. The structures of all the complexes were determined by means of 1H NMR, 13C NMR and 31P NMR spectroscopic methods and further confirmed by single-crystal X-ray diffraction analysis. When activated with methylaluminoxane (MAO) at a ratio of Al/Ti=600 and under 0.5 MPa of ethylene, these bimetallic Ti phosphinimine complexes displayed a higher catalytic activity compared to the monometallic analogues, but resulted in polymers with bimodal molecular weight distributions. Unexpectedly, 6b produced ultrahigh Mw polyethylene at lower polymerization temperature.
AB - Mono-and bisdiphenyl substituted heteroarylphosphines R-PPh2[R=2-pyridyl (3a), 2-thienyl (3b) and 2-furyl (3c)] and Ph2P-R'-PPh2[R'=2,6-pyridyl (6a), 2,5-thienyl (6b) and 2,5-furyl (6c)] were synthesized. After Staudinger reaction with Me3SiN3, those heteroarylphosphines were converted into the heteroarylphosphinimine ligands, R-PPh2(NSiMe3) and (Me3SiN)Ph2P-R"-PPh2(NSiMe3). The subsequently dehalosilylation reaction with CpTiCl3 afforded the corresponding Ti heteroarylphosphinimine halfmetallocenes as olefin polymerization catalysts. The structures of all the complexes were determined by means of 1H NMR, 13C NMR and 31P NMR spectroscopic methods and further confirmed by single-crystal X-ray diffraction analysis. When activated with methylaluminoxane (MAO) at a ratio of Al/Ti=600 and under 0.5 MPa of ethylene, these bimetallic Ti phosphinimine complexes displayed a higher catalytic activity compared to the monometallic analogues, but resulted in polymers with bimodal molecular weight distributions. Unexpectedly, 6b produced ultrahigh Mw polyethylene at lower polymerization temperature.
KW - Bimetallic titanium catalyst
KW - Ethylene polymerization
KW - Heteroaryl
KW - Phosphinimine
UR - http://www.scopus.com/inward/record.url?scp=85058809521&partnerID=8YFLogxK
U2 - 10.6023/cjoc201803035
DO - 10.6023/cjoc201803035
M3 - Article
AN - SCOPUS:85058809521
SN - 0253-2786
VL - 38
SP - 2151
EP - 2160
JO - Chinese Journal of Organic Chemistry
JF - Chinese Journal of Organic Chemistry
IS - 8
ER -