Coordination Diversity of Aluminum Centers Molded by Triazole Based Chalcogen Ligands

Self-Assembly of Aluminum- and Gallium-Based meso-Metallaporphyrins

The molecular meso-metallaporphyrin has been obtained from the reaction of AlMe₃ with the bulky 4,5-(Ph₂(HO)C)₂-1,2,3-triazole (1). The presence of Al-Me groups coordinated to the triazole rings creates three different stereoisomers that were identified by single-crystal X-ray diffraction. Further studies revealed that, for steric reasons, only one of the two main stereoisomers is active in the polymerization of ε-caprolactone. When GaMe₃ is used instead of AlMe₃, a trimetallic species is formed instead of the meso-metallaporphyrin pointing to a metal-directed self-assembly. On the other hand, the reaction of the monolithium salt [{Li(THF)₂}{κ²- N, N'-4,5-(Ph₂(HO)C)-1,2,3-triazole}]₂ (2; THF = tetrahydrofuran) with MCl₃ (M = Al, Ga) yields meso-metallaporphyrin species with a lithium atom in the center of the metallacycle. While the gallium derivative is rather stable in solution, the aluminum analogue decomposes rapidly. In the solid state, continuous cationic columns running throughout the whole crystal are formed from alternating Li⊂[M]₄ (M = Al, Ga) meso-metallaporphyrin and [Li(THF)₄]⁺ cations. Density functional theory calculations determined that the weak Cl···H, H···H, N···H, and Cl···O interactions with a total interaction energy of -38.6 kcal·mol^-1 are responsible for this unusual packing.

Metal-directed self-assembly of transition metal heterometallascorpionates

3d metal-based heterometallascorpionates featuring high-spin Co(ii) and Ni(ii) centers were prepared and their structural, magnetic and electronic properties investigated.

Facile Route to Rare Heterobimetallic Aluminum-Copper and Aluminum-Zinc Selenide Clusters

Heterobimetallic aluminum-copper and aluminum-zinc clusters were prepared from the reaction of LAl(SeH)₂ [1; L = HC(CMeNAr)₂ and Ar = 2,6-iPr₂C₆H₃] with (MesCu)₄ and ZnEt₂, respectively. The resulting clusters with the core structures of Al₂Se₄Cu₄ and Al₂Se₄Zn₃ exhibit unique metal-organic frameworks. This is a novel pathway for the synthesis of aluminum-copper and aluminum-zinc selenides. The products have been characterized by spectroscopic methods and single-crystal X-ray structural characterization.

Hydrogen and oxygen activation by an iridium precursor containing the 4,5-bis(diphenylthiophosphinoyl)-1,2,3-triazolate ligand

Complex [Ir(κ²-S,N-(4,5-(P(S)Ph₂)₂Tz))(coe)₂] (coe = cyclooctene) was prepared upon reaction of potassium 4,5-bis(diphenylthiophosphinoyl)-1,2,3-triazolate with [Ir(coe)₂(μ-Cl)]₂. Its phosphorus derivatives were susceptible of oxidative addition processes.

Aluminum Dimer Containing Bulky 1,2,3-Triazolate Ligand

The first molecular aluminum 1,2,3-triazolato complex was synthesized bearing a bulky 1,2,3-triazolate ligand. Oligomers and polymers were avoided due to the bulkiness and noncoordinating nature of the substituents. The novel Al2N4ring formed contains symmetrical Al-N bond distances unexpectedly having asymmetric Al-N-N angles of 144.55(15)° and 115.83(14)°. This asymmetry demonstrates the effect of the steric hindrance of the ligand.