Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5160168 | Journal of Molecular Structure | 2017 | 7 Pages |
Abstract
Two novel half-sandwich Ti complexes, both incorporating two adamantoxy (OAd) ligands coordinated to their central atoms were synthesized. The complexes were characterized by 1H, 13C, 19F NMR, EI-MS and IR spectroscopy and by single-crystal X-ray diffraction. In both complexes, the coordination environment is pseudo-tetrahedral and is assembled of two O-coordinated adamantoxy and one η5-coordinated permethylcyclopentadienyl ligand. The fourth ligand in complex 1 is a methyl group coordinated through a regular Ï-bond, whereas in complex 2 the same coordination site is occupied by the methyl group of the balancing (C6F5)3BMeË anion. DFT computations complemented with NBO analyses of 2 have unveiled, that in addition to the electrostatic interactions occurring between the half-sandwich titanocene moiety and the anionic ligand, delocalization of one methyl CH bond into the available acceptor orbital on the central atom takes place. AIM analyses of 2 have revealed the presence of a Bond Critical Point between the metal atom and the anionic methyl group. These results prove foundation for the description of 2 as a zwitterionic complex coupled with a concurrent Tiâ¯CH agostic interaction in its molecule. The comparison of 2 with its analogous complex equipped with two Ot-Bu ligands instead of both OAd has suggested only a minor change in the extent of the agostic interaction, despite significant geometric differences between the two complexes.
Keywords
Related Topics
Physical Sciences and Engineering
Chemistry
Organic Chemistry
Authors
Vojtech Varga, Karel Mach, JiÅà Pinkas, JiÅà KubiÅ¡ta, KatarÃna Szarka, Róbert Gyepes,