Titanacalixarenes in Homogeneous Catalysis: Synthesis, Conformation and Catalytic Activity in Ethylene Polymerisation

✍ Scribed by Jeff Espinas; Ulrich Darbost; Jeremie Pelletier; Erwan Jeanneau; Christian Duchamp; François Bayard; Olivier Boyron; Jean-Pierre Broyer; Jean Thivolle-Cazat; Jean-Marie Basset; Mostafa Taoufik; Isabelle Bonnamour

• Book ID: 102829288
• Publisher: John Wiley and Sons
• Year: 2010
• Tongue: English
• Weight: 630 KB
• Volume: 2010
• Category: Article
• ISSN: 1434-1948
• DOI: 10.1002/ejic.200901185

✦ Synopsis

Abstract

Variously substituted titanacalixarenes were synthesised and tested for their performance as catalysts in ethylene polymerisation: p‐tert‐butylcalix[4]arene was derivatised to afford distal diether p‐tert‐butylcalix[4]arenes L1–L4, distal dihydroxy‐depleted L5, proximal dihydroxy‐depleted L6, proximal diether p‐tert‐butylcalix[4]arene L7, proximal intrabridged disiloxane L8 and proximal monoether L9. (Dichlorotitana)‐p‐tert‐butylcalix[4]arenes 1–8 and (monochlorotitana)‐p‐tertbutylcalix[4]arene 9 have been successfully synthesised by reacting L1–L4 with TiCl~4~**·**2THF or L5–L9 with TiCl~4~. The structural conformation of complexes 1–9 in solution were determined by ^1^H NMR, ^13^C NMR, NOESY and COSY spectroscopic studies. Compounds 2, 3 and 4 have been structurally characterised by single‐crystal X‐ray diffraction. Upon activation with methylaluminoxane, compounds 1–8 revealed low to moderate activities for the production of high‐density polyethylene (HDPE) to ultra‐high‐molecular‐weight polyethylene (UHMWPE). 6/MAO gave the best activity at 770 kg~PE~ (mol Ti)^–1^ h^–1^.