The synthesis and X-ray structure of the first exclusively N-based tetrameric complex [RAl]4 (1; R = 2,6-iPr2C6H3N(SiMe3)) are reported. 1 was prepared by the reduction of [RAlI2]2 (2) with Na/K alloy.

The syntheses of the ionic compounds [Li(+).2 dioxane (2,6-iPr(2)C(6)H(3)N(SiMe(3))Al(C triplebond CSiMe(3))(3))(-)].0.75 dioxane (1), [(Li(+))(2).(dioxane)(7)](0.5) [2,6-iPr(2)C(6)H(3)N(SiMe(3))Ga(C triplebond CSiMe(3))(3)(-)].1.5 dioxane (2), and [(Li(+))(2).(dioxane)(7)](0.5) [2,6-iPr(2)C(6)H(3)N(SiMe(3))In(C triplebond CSiMe(3))(3)(-)].1.5 dioxane (3) by the reaction of the corresponding organo metal chloride with LiC triplebond CSiMe(3) are reported. The neutral ethynyl compounds Br-Al(C triplebond CtBu)(2).2 THF (4), Cl-Ga(C triplebond CtBu)(2).THF (5), Cl-In(C triplebond CtBu)(2).2 THF (6), Al(C triplebond CtBu)(3).C[N(Me)CMe](2) (7), Ga(C triplebond CtBu)(3).dioxane (8), and In(C triplebond CtBu)(3).NEt(3) (9) have been obtained in good yields from the reaction of AlBr(3), GaCl(3), and InCl(3) with LiC triplebond CtBu in the presence of a Lewis base. Compound 7 is the first heterocyclic carbene substituted ethynyl derivative. Aluminum and gallium compounds with three terminal ethynyl groups Al(C triplebond CPh)(3).NMe(3) (10) and Ga(C triplebond CPh)(3).NMe(3) (11) have been prepared by the reaction of AlH(3).NMe(3) or GaH(3).NMe(3) with three equivalents of phenylethyne. All the above-mentioned compounds have been structurally studied. In compound 1 the lithium ion is coordinated to the three terminal ethynyl groups, whereas in compounds 2 and 3 the lithium is coordinated to the solvent (dioxane). Compound 8 crystallizes as a coordination polymer with dioxane molecules bridging the individual gallium units.

[Al3(μ3-O)(μ-O2CCF3)6(THF)3][(Me3Si)3CAl(OC(O)CF3)3]·C7H8 is the first characterized μ3-oxo-trinuclear basic carboxylate of aluminum closing the gap of isomorphism with the transition metal analogues. The system is an excellent case study for the electronic structure, approached by DFT-B3LYP calculations. The actual system proves that the oxo-trinuclear pattern is stabilized by the chemical hardness of oxygen donors and by highly symmetric intramolecular packing of the ligands.

The synthesis of [K + ‚THF(2,6-iPr 2 C 6 H 3 N-(SiMe 3 )Al(CtCPh) 3 ) -] 2 (1), [Na + ‚THF (2, 4) with the corresponding phenylethynyl alkali metal salt is reported. In compound 1 the potassium (2, sodium) interacts with the CtC bonds of four phenylethynyl groups. A further coordination site of the potassium (sodium) is occupied by a THF molecule. Thus, the cation therein acts as a bridging moiety to form the dimer. In compound 3 each of the lithium cations is 2-fold coordinated by phenylethynyl ligands and two dioxane molecules. One of the dioxane molecules in 3 functions as a bridge forming the dimer. The herein described compounds are the first structurally characterized species having three terminal phenylethynyl groups bound to the aluminum atom.

The synthesis of [((Me 3 Si) 3 CAlF 2 ) 2 (µ-O)Li 2 -(THF) 4 ] (1) and [{Li(Me 3 Si) 3 CAlF 3 (THF)} 3 LiF(THF)] (2) is reported. Compound 1 was obtained either by the reaction of (Me 3 Si) 3 CAlMe 2 ‚THF and Me 3 SnF in the presence of Li 2 O or by the reaction of [(Me 3 Si) 3 CAlF 2 ] 3 and Li 2 O. 1 is an interesting example of an oxygen-and fluorine-containing alkyl aluminum compound. Complex 2 was prepared by the reaction of (Me 3 Si) 3 CAlF 2 ‚THF with LiOCH(CF 3 ) 2 as an unexpected result that illustrates the variety of possible structures obtainable by the combination of [(Me 3 Si) 3 CAlF 2 ] 3 and LiF.