Synthesis and structures of aluminium monohydride and chalcogenides bearing a bidentate [N,O] ligand

Abstract

The aluminium monohydride (3-tBu-5-Me-2-(O)C₆H₂CH₂-N-2,6-iPr₂C₆H₃)AlH(NMe₃) (2) was prepared by treatment of the bidentate salicylaldimine [3-tBu-5-Me-2-(OH)C₆H₂CHN-2,6-iPr₂C₆H₃] (1) with a small excess of AlH₃·NMe₃ in high yield. Compound 2 reacted with sulfur and selenium respectively to afford the dimeric aluminium chalcogenide [(3-tBu-5-Me-2-(O)C₆H₂CH₂-NH-2,6-iPr₂C₆H₃)Al(μ-E)]₂ [E = S (3), E = Se (4)]. During the formation of 2 hydrogen migration from the aluminium centre to the ligand backbone occurred. A possible reaction mechanism for 3 and 4 is discussed and the molecular structures of compounds 2–4 were determined by X-ray structural analyses.