Popis: |
The Lewis acid–base reaction of 2,6-bis[1,3-di- tert -butylimidazolin-2-imino)methyl]pyridine (TL t Bu ) and LnCl 3 in THF leads to the corresponding neutral lanthanide complexes of type [(TL t Bu )LnCl 3 ], Ln = Y ( 1a ), Er ( 1b ), Lu ( 1c ). The yttrium and lutetium complexes have been characterized by X-ray diffraction analysis. The solid state structures reveal that the bulky TL t Bu ligand causes steric crowding around the lanthanide atoms by coordinating to the metal center in a tridentate fashion. In addition, remote C–H⋯Ln interactions (H⋯Ln ca. 2.7 A) involving one of the t Bu methyl groups are observed in both cases. A DFT (density functional theory) calculation on 1a was able to reproduce this interaction, which was additionally characterized by means of an H⋯Y compliance constant and by employing the AIM (atoms in molecules) theory. |