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The novel amino- and iminometallanes (MeAlNRf)n (1) (n = 4, 1a; n = 6, 1b), (Me2GaN(H)Rf)2 (2), (MeGaNRf)6 (3), (Me2InN(H)Rf)2 (4), and (MeIn(THF)NRf)4 (5) (Rf = 4-C6H4F) have been prepared in high yield by the reaction of AlMe3, GaMe3, and InMe3, respectively, with 4-fluoroaniline. All of the products have been fully characterized by elemental analysis, IR, NMR, and mass spectroscopy. The crystal structures of 1a, 1b·2THF, 3·7THF, and 5 have been determined. For the degree of oligomerization of compound 1 a solvent- and temperature-dependent influence is assumed. (MeGaNRf)6 (3) is the first hexameric iminogallane and (MeIn(THF)NRf)4 (5) is the second iminoindane described in the literature.

Aminodimethylalanes R¹R²NAlMe2 (R¹ = 2,6-i-Pr2C6H3, 2,6-Me2C6H3; R² = SiMe3, Si(i-Pr)Me2, Si(t-Bu)Me2, Si(2,4,6-Me3C6H2)Me2) are prepared in high yield via reaction of the respective amine R¹R²NH with trimethylaluminum in n-hexane. Further reaction of (2,6-i-Pr2C6H3)N(SiMe3)AlMe2 with 2 equiv of trimethyltin fluoride in toluene affords the aminoalane difluoride (2,6-i-Pr2C6H3)N(SiMe3)AlF2. An X-ray structural determination of (2,6-i-Pr2C6H3)N(SiMe3)AlMe2 shows it to be dimeric with bridging methyl and terminal amino groups. The aminoalane difluoride (2,6-i-Pr2C6H3)N(SiMe3)AlF2 is trimeric with a six-membered alternating aluminum−fluorine ring. Terminal fluorine atoms are located above and below the ring. Reactions of aminoalanes R¹R²NAlMe2 with 2 equiv of trimethyltin fluoride in THF yield the monomeric THF adducts R¹R²NAlF2·THF.

The novel bulky alkylaluminum dihalogenides [(Me3Si)3CAlX2·THF] (X = F, 1; X = Cl, 4; X = Br, 5; X = I, 6) and dialkylaluminum halogenides [(Me3Si)3CAl(Me)X·THF] (X = Cl, 8; X = Br, 9; X = I, 10) have been prepared by reaction of the mixed trialkylalane [(Me3Si)3CAlMe2·THF] with Me3SnX (X = F, Cl) and X2 (X = Br, I) in a 2:1 and 1:1 molar ratio, respectively. The coordinated THF molecule of compound 1 can be removed by heating in vacuo to yield the trimeric solvent-free organoaluminum difluoride [{(Me3Si)3CAlF2}3] (2). Compound 2 shows no cocatalytic activity with group 4 metallocenes for ethylene polymerization. Reaction of [(Me3Si)3CAlF2·THF] (1) with potassium fluoride gave the unusual coordination compound [{(THF)2K(Me3Si)3CAlF2(μ-F)F2AlC(SiMe3)3}2] (3). The molecular structures of compounds 2−6 have been determined by X-ray structure analysis. Compound 2 is the first structurally characterized organoaluminum difluoride, and 6 is the first structurally characterized organoaluminum diiodide.

Lithium (2,6-diisopropylphenyl)(trimethylsilyl)amide (2,6-iPr2C6H3N(SiMe3)Li) reacts with MCl4 (M = Zr, Hf) in a 2:1 molar ratio to give [{2,6-iPr2C6H3N(SiMe3)}2MCl2] (1a, M = Zr; 1b, M = Hf) and with (C5Me5)MCl3 (1:1) to give [(C5Me5){2,6-iPr2C6H3N(SiMe3)}MCl2] (2a, M = Zr; 2b, M = Hf). Further reaction of the dichlorides (1a,b, 2a,b) with Me3SnF leads to the corresponding difluorides [{2,6-iPr2C6H3N(SiMe3)}2MF2] (3a, M = Zr; 3b, M = Hf) and [(C5Me5){2,6-iPr2C6H3N(SiMe3)}MF2] (4a, M = Zr; 4b, M = Hf). The compounds 1−4 were investigated as potential catalysts for the polymerization of olefins, in combination with methylaluminoxane (MAO). For the first time the catalytic activities, toward the polymerization of ethylene, of chlorides and the corresponding fluorides are compared under identical conditions. The solid-state structures of 1a,b, 2b, 3a, and 4a were determined by single-crystal X-ray diffraction.