An unprecedented aluminum hydroxide LAlMe(OH) (5; L = HC[(CMe)(2,6-iPr2C6H3N)]2) has been prepared by the hydrolysis of LAlMeCl (4). For the preparation of 5, the reagents of KOH, water, and KH, as well as the two-phase ammonia/toluene system, were used. Further reactions of 5 with Cp2ZrMe2 (8) and Cp2ZrHCl in toluene lead to the intermolecular elimination of CH4 and H2 and the formation of mu-O-bridged dinuclear aluminum and zirconium complexes [LAlMe(mu-O)ZrMeCp2] (6) and [LAlMe(mu-O)ZrClCp2] (7), respectively, in high yields. The crystal structure reveals that 5 is a monomer with terminal OH and Me groups. The X-ray structure analysis shows that 6 and 7 contain a bent Al-(mu-O)-Zr core with terminal Al-Me and Zr-Me or Zr-Cl arrangements. The methylalumoxane (MAO)-activated compounds 6 and 7 exhibit high catalytic activity for the polymerization of ethylene. Under comparable polymerization conditions, the MAO/6 and MAO/7 catalyst systems show considerably higher activity and much lower MAO:catalyst ratios than that of MAO/8.

A series of organometallic compounds of group 13 metals supported by the sterically encumbered beta-diketiminate ligand containing hydrides, fluorides, chlorides, and bromide have been synthesized and structurally characterized. The synthetic strategy applied utilizes halide metathesis and reduction of metal chlorides to the corresponding hydrides. Thus, the reaction of LLi.OEt2 with MeMCl2 affords LM(Me)Cl (M = Al (1), Ga (2), In (3)) and LGaBr2 (4) with GaBr3. Reduction of LGa(Me)Cl with LiH.BEt3 leads to the formation of LGa(Me)H (10). Synthesis of LGaH(2) (12) has been accomplished by reacting LGaI2 (8) with LiH.BEt3. LAl(Me)Cl (1) and LAlH2 (6) have been converted to LAl(Me)F (5) and LAlF2 (7), respectively. The former was obtained in a reaction of LAl(Me)Cl with Me3SnF while the latter was isolated in a reaction of LAlH2 with BF3.OEt2. Similarly reaction of LGaI2 (8) with Me3SnF affords LGaF2 (9). Compounds reported herein have been characterized by elemental analyses, IR, NMR, EI-MS, and single-crystal X-ray diffraction techniques.

Synthesis of a new class of compounds containing a Ln-O-Al moiety has been accomplished by the reaction of LAlOH(Me) (L = HC(CMeNAr)(2), Ar = 2,6-iPr(2)C(6)H(3)) with a series of Cp(3)Ln compounds. The terminal Al-OH group shows selective reactivity, and the complexes Cp(2)Ln(THF)-O-AlL(Me) (Ln = Yb, 1; Er, 2; Dy, 3), Cp(2)Yb-O-AlL(Me) (4), and Cp(3)Ln(mu-OH)AlL(Me) (Ln = Er, 5; Dy, 6; Sm, 7) were obtained. This allows further insight into the proton exchange process, and two different mechanisms, intermolecular and intramolecular elimination of CpH, are proposed under different conditions. Complexes 1-4, 6, and 7 have been characterized by X-ray structural analyses which reveals a Ln-O-Al or Ln(mu-OH)Al core in these complexes. The obtuse Ln-O-Al angles fall in the range 151.9-169.8 degrees . The reaction of 1 or 4 with Me(3)SnF in toluene under refluxing conditions unexpectedly yielded the compounds [Cp(2)Yb(mu-OSnMe(3))](2) (8) and LAl(Me)F (9). Reactions of LAlOH(Me) with the mono- and dicyclopentadienyl complexes LYbCp(Cl) (10) and LYbCp(2) (11) supported by the bulky beta-diketiminate ligand were unsuccessful. However, the reaction of LAl(OH)Me with LYbN(SiMe(3))(2)Cl (12) containing a labile Yb-N bond leads to the formation of LYbCl-O-AlL(Me) (13) under elimination of HN(SiMe(3))(2). Furthermore, complexes 1, 3, 4, and 6 exhibit good catalytic activity for the polymerization of epsilon-caprolactone.

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