Pendant arm Schiff base complexes of aluminium as ethylene polymerisation catalysts

The potentially tridentate Schiff base ligands [3,5-But2-2-(HO)C6H2CHNL] 1, on reaction with Me3Al at room temperature, afford the complexes [(3,5-But2-2-(O)C6H2CHNL)AlMe2] [L = CH2CH2NMe2 2a, (2-PhO)C6H4 2b, 2-CH2C5H4N 2c and 8-C9H6N (quinoline) 2d], 2a and 2c have been characterised crystallographically; further reaction of the dimethyl compounds with B(C6F5)3 affords the cationic systems [(3,5-But2-2-(O)C6H2CHNL)AlMe]+ 3a–d of which 3a and 3b are ethylene polymerisation catalysts.