960化工网
Chromium complexes bearing amidinato-phosphino ligand: synthesis, characterization, and catalytic properties of ethylene tri-/tetramerization and polymerization†
Rui Liu,Kongtao Zhu,Xianghong Zhong,Jiancheng Li,Zhenyu Liu,Shibing Chen,Hongping Zhu
Dalton Transactions Pub Date : 09/22/2016 00:00:00 , DOI:10.1039/C6DT03216H
Abstract

An amidinato-phosphino ligand ArN[double bond, length as m-dash]C(R)NH(o-Ph2PC6H4) (Ar = 2,4,6-Me3C6H2, R = Ph (1); Ar = 2,6-iPr2C6H3, R = Ph (2); Ar = 2,6-iPr2C6H3, R = tBu (3)) was prepared. The ligand reacted with CrCl3(THF)3 to yield the N,P-chelation complex [ArNHC(R)[double bond, length as m-dash]N(o-Ph2PC6H4)]CrCl3(THF) (4–6), and the ligand’s lithium salt ArN[double bond, length as m-dash]C(R)N(o-Ph2PC6H4)Li reacted with the respective CrCl3(THF)3 and CrCl2(THF)2 to give the N,N,P-chelation complexes [ArN[double bond, length as m-dash]C(R)N(o-Ph2PC6H4)]CrCl2(THF) (7–8) and {[ArN[double bond, length as m-dash]C(R)N(o-Ph2PC6H4)]Cr(μ-Cl)}2 (9–11). Complexes 1–11 were characterized by IR, NMR (for 1–3), EPR (for 4–11) spectroscopy and CHN elemental analysis, of which 3, 5, 8, and 11 were further studied by X-ray crystallography. Upon activation with an organoaluminum cocatalyst, complexes 4–6 were all catalytically active in ethylene tri-/tetramerization along with ethylene polymerization, and complexes 7–11 functioned as well but in ethylene polymerization. The correlation between the structure and the catalytic properties of the catalyst system is discussed.

Graphical abstract: Chromium complexes bearing amidinato-phosphino ligand: synthesis, characterization, and catalytic properties of ethylene tri-/tetramerization and polymerization
平台客服
平台客服
平台在线客服