Oxide‐Bridged Heterobimetallic Aluminum/Zirconium Catalysts for Ethylene Polymerization. Issue 12 (17th March 2015)

• Record Type: Journal Article
• Authors: Boulho, Cédric; Zijlstra, Harmen S.; Harder, Sjoerd
• Is Part Of: European journal of inorganic chemistry. Issue 12(2015)
• Page Start: 2132
• Page End: 2138
• Publication Date: 2015-03-17
• Subjects: Sandwich complexes -- Heterometallic complexes -- Zirconium -- Polymerization -- Polyethylene; Chemistry, Inorganic -- Periodicals; Organometallic chemistry -- Periodicals; Bioinorganic chemistry -- Periodicals; Solid state chemistry -- Periodicals; 546
• DOI: 10.1002/ejic.201500123
• Languages: English
• ISSNs: 1434-1948

Abstract

Abstract: A bimetallic aluminum/zirconium complex Cp*2 Zr(Me)OAl(DIPH) [DIPH‐H2 = 3, 3′‐bis(2‐methylallyl)‐(1, 1′‐biphenyl)‐2, 2′‐diol; Cp* = C5 Me5 ] was prepared in good yield by the reaction of (DIPH)AlMe with Cp*2 Zr(Me)OH. In contrast to Roesky's catalyst, Cp2 Zr(Me)O(Me)Al(DIPP‐nacnac) {DIPP‐nacnac = CH[(CMe)(2, 6‐ i Pr2 C6 H3 N)]2 }, it contains no Al–Me functionality and has increased Lewis acidity at Al. Crystal structures and the NMR spectra of the aluminum complex (DIPH)AlMe and the bimetallic Al/Zr species reveal in both cases dimeric complexes. The crystal structure of [Cp*2 Zr(Me)OAl(DIPH)]2 shows a planar Al2 O2 core and a terminal Cp*2 Zr(Me)O group. Ethylene polymerization in toluene was studied for the bimetallic complex with a variety of scavengers. Under comparable polymerization conditions, the methylalumoxane‐activated species show high activities that are similar to those obtained with Cp*2 ZrCl2 and Roesky's bimetallic complex Cp2 Zr(Me)OAl(Me)(DIPP‐nacnac), with a relatively narrow polydispersity index (2.47). Abstract : The targeted synthesis of a new bimetallic aluminum/zirconium species with remaining Lewis acidity on aluminum gives a dimeric Al–O–Zr complex. In the presence of methylalumoxane, this μ‐oxo complex is able to activate ethylene to produce polyethylene with high activity.