Chelated anionic aluminum

Two equivalents of the bidentate ligands, 2,4-(R)(2)-6-(CH2NHR')PhOH (where R' = alkyl and R = H (L-1) and Bu-t(L-2)) are combined with LiAlH4 to form unique chelated aluminates of the form [(L-1)(2) Al]Li(THG)(2) (R' = Pr-i (1), Bu-i (2), Bu-t (3), Dipp (4) (Dipp = 2,6-(Pr-i)(2)Ph)) and [(L-2)(2)Al ]Li(THF)(2) (R' = Pr-i (5), Bu-i(6), Bu-t(7)). Compound 7 undergoes salt el imination when combined with Me2AlCl to form the bimetallic derivative, (L- 2)(2)Al (AlMe2) (R' = Bu-t (8)). By comparison a related reaction with [ArO 4Al][Li(thf)(4)] (Ar = 2,4-(Bu-t)(2)Ph (9)) leads to elimination of one of the aryloxide groups and the consequent formation of neutral species. All o f the compounds were characterized by Mp, analyses, H-1 NMR, IR and, in the case of 4 and 7 - 9, by X-ray crystallography.