Chiral five- and six-coordinate aluminum

The chiral five-coordinate halide compound, Salcen(tBu)AlCl (1) (Salcen = N ,N'-cyclohexy lenebis(3, 5-di-tert-butylsalicylideneimine) can be used in a salt elimination reaction to produce [R,R'Salcen(tBu)AlOTs] (2) as well as the chiral cationic complex, [R,R'Salcen (tBu)Al(thf)(2)]+BPh4- (3). The c onditions under which these types of neutral and cationic complexes form wi ll be discussed. This should provide guidance for the eventual use of the c ations as strongly Lewis acidic catalysts and organic synthetic reagents.