Reactivity and derivatization of five-coordinate, chelated aluminum

The convenient five-coordinate starting materials, Salen('Bu)AlCl (Salen('Bu) = NX-alkylene (or arylene) bis (3,5-di-tert-butyl-2-hydroxybenzylideneamine) (1-4) can be used in a wide range of reactions to form five-coordinate aluminum compounds. Herein, these reagents were used to produce new five-coordinate azides, LAIN(3) (L = Salen('Bu) (5). Salpen('Bu) (6). and Salomphen('Bu) (7)) through trimethylsilylhalide elimination. The decomposition of the azides produce first hydroxide (LAlOH (L = Salen('Bu) (8)) and, subsequently in the presence of chlorotrimethylsilane, the siloxide compounds, LAlOSiMe3 (L = Salen('Bu) (9), Salpen('Bu) (10), and Salomphen('Bu) (11)). Alkane elimination reactions may also be used to access this type of compound as evidenced by the formation of Salomphen('Bu)AlOSiPh3 (12). Additionally. the First structurally characterized five-coordinate monomeric amide, Salcen('Bu)AlN(SiMe3)(2) (13), can prepared by a salt elimination utilizing Salcen('Bu)AlCl (4). The compounds were characterized by spectroscopic methods (H-1 and Al-27 NMR. MS, and IR) and, in the case of 2 (Salpen('Bu)AlCl), 3 (Salomphen('Bu)AlCl) 9, 11, 12, and 13, by X-ray analysis, Several of the compounds were explored as potential catalysts for the living polymerization of propylene oxide.