353493-72-8Relevant academic research and scientific papers
Synthesis and characterisation of neutral dialkylaluminium complexes stabilised by salicylaldiminato ligands, and their conversion to monoalkylaluminium cations
Cameron, Paul A.,Gibson, Vernon C.,Redshaw, Carl,Segal, John A.,Solan, Gregory A.,White, Andrew J.P.,Williams, David J.
, p. 1472 - 1476 (2008/10/08)
Treatment of the salicylaldimine ligands 3,5-Bu2t-2-(OH)C6H2CHNR [R = 2,6-M2C6H3 (1a), 2,6-Pr2iC6H3(1b), 3,5-(CF3)2C6H3 (1c), 4-(NO2)C6H4 (1d), 4-ClC6H4 (1e), 1-naphthyl (1f), But (1g)] with Me3Al in toluene yields, after work-up, the highly crystalline (except 2c - an oil) complexes {3,5-Bu2t-2-(O)C6H2CH=NR} AlMe2 [R = 2,6-Me2C6H3 (2a), 2,6-Pr2iC6H3 (2b), 3,5-(CF3)2C6H3 (2c), 4-(NO2)C6H4 (2d), 4-ClC6H4 (2e), 1-naphthyl (2f), But (2g)] respectively. Reaction of these systems with B(C6F5)3 in the presence of THF leads smoothly to [{3,5-Bu2t-2-(O)C6H2CH=NR}-AlMe(THF) ]+ [R = 2,6-Me2C6H3 (3a), 2,6-Pr2iC6H3 (3b), 3,5-(CF3)2C6H3 (3c), 4-(NO2)C6H4 (3d), 4-ClC6H4 (3e), 1-naphthyl (3f), But (3g)], as the B(C6F5)3Me- salts. By contrast, the same reaction performed in dichloromethane solution without THF gives complex mixtures: the NMR spectrum of the product mixture obtained from the reaction of 2g with B(C6F5)3 in CD2Cl2 indicated, inter alia, the presence of both {3,5-Bu2t-2-(O)C6H2CH=NBut }-AlMe(C6F5)] and B(C6F5)2Me. Compounds 2a and 2b have been characterised by single crystal X-ray structure determinations and shown to have virtually identical conformations. In both systems there is a marked distortion in the tetrahedral geometry at the aluminium centre.
