Tuning the Size and Geometry of Heteroleptic Coordination Cages by Varying the Ligand Bent Angle |
| |
Authors: | Dr Ru-Jin Li Dr Farzaneh Fadaei-Tirani Dr Rosario Scopelliti Prof Kay Severin |
| |
Institution: | Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland |
| |
Abstract: | Spherical assemblies of the type PdnL2n]2n+ can be obtained from PdII salts and curved N-donor ligands, L. It is well established that the bent angle, α, of the ligand is a decisive factor in the self-assembly process, with larger angles leading to complexes with a higher nuclearity, n. Herein, we report heteroleptic coordination cages of the type PdnLnL′n]2n+, for which a similar correlation between the ligand bent angle and the nuclearity is observed. Tetranuclear cages were obtained by combining Pd(CH3CN)4](BF4)2 with 1,3-di(pyridin-3-yl)benzene and ligands featuring a bent angle of α=120°. The use of a dipyridyl ligand with α=149° led to the formation of a hexanuclear complex with a trigonal prismatic geometry; for linear ligands, octanuclear assemblies of the type Pd8L8L′8]16+ were obtained. The predictable formation of heteroleptic PdII cages from 1,3-di(pyridin-3-yl)benzene and different dipyridyl ligands is evidence that there are entire classes of heteroleptic cage structures that are privileged from a thermodynamic point of view. |
| |
Keywords: | coordination cages heteroleptic cages palladium pyridyl ligands supramolecular chemistry |
|
|