A remarkable inversion of structure-activity dependence on imido N-substituents with varying co-ligand topology and the synthesis of a new borate-free zwitterionic polymerisation catalyst.
Ethylene polymerisation productivities of tris(pyrazolyl)methane-supported catalysts [Ti(NR){HC(Me2pz)3}Cl2] show a dramatically different dependence on the imido R-group compared to those of their TACN analogues, attributed to differences in fac-N3 donor topology; when treated with AliBu3, the zwitterionic tris(pyrazolyl)methide compound [Ti(N-2-C6H4tBu){C(Me2pz)3}Cl(THF)] also acts as a highly active, single site catalyst (TACN = 1,4,7-trimethyltriazacyclononane).
Chemistry Research Laboratory, University of Oxford, Mansifeld Road, Oxford, UK OX1 3TA.
Helen R
HR
Bigmore
Stuart R
SR
Dubberley
Mirko
M
Kranenburg
Sally C
SC
Lawrence
Andrew J
AJ
Sealey
Jonathan D
JD
Selby
Martin A
MA
Zuideveld
Andrew R
AR
Cowley
Philip
P
Mountford
D001372:Aza Compounds / Q000138:chemical synthesis*; D001881:Borates / Q000737:chemistry; D002384:Catalysis; D007094:Imides / Q000737:chemistry*; D008024:Ligands; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis*; D011108:Polymers / Q000737:chemistry; D011720:Pyrazoles / Q000138:chemical synthesis*; D014025:Titanium / Q000737:chemistry*
C499747:1,4,7-trimethyl-1,4,7-triazacyclononane; D001372:Aza Compounds; D001881:Borates; D007094:Imides; D008024:Ligands; D009942:Organometallic Compounds; D011108:Polymers; D011720:Pyrazoles; C515920:tris(pyrazolyl)methane; D014025:Titanium