光谱学与光谱分析, 2016, 36 (11): 3737, 网络出版: 2016-12-30
The Intramolecular Spin-Spin Interactions in Ruthenium Complexes of Pyrazole Derivatives
The Intramolecular Spin-Spin Interactions in Ruthenium Complexes of Pyrazole Derivatives
摘要
Abstract
The spin-spin coupling can provide useful information for analysing the structure of a system and the extent of non-covalent bonds interactions. In this study, we present the isotropic NMR properties and spin-spin coupling involving ruthenium-ligand (Ru-L) bonds and other spin-spin interactions obtained from DFT calculations. The proton shift which in close proximity with the Ru and Cl (or O) atoms are characterised with lower and higher chemical shift respectively. Though Ru-Cl bond has longer bond length than all other Ru-L bonds, yet its spin-spin coupling is higher than others because of a very high contribution of PSO which is far higher than the contribution from FC terms. In all other Ru-L bonds, FC is the most significant Ramsey terms that define their spin-spin coupling. Both the isotropic and anisotropic shielding of the Hz of the pyrazole is lower than Hc of the cymene and the spin-spin coupling 3J(Hz…Hz) of the pyrazole are less than half of the 3J(Hc…Hc) of the cymene unit in the complexes. There is a little increase in both the 3J(Hc…Hc) and 3J(Hz…Hz) spin-spin coupling in the hydrolysed complexes compare to the non-hydrolysed complexes. The isotropic and anisotropic shielding tensor of Ru atoms increases in magnitude as the complexes get hydrolysed that could be ascribed to a more deshielding chemical environments.
Peter A. Ajibade. The Intramolecular Spin-Spin Interactions in Ruthenium Complexes of Pyrazole Derivatives[J]. 光谱学与光谱分析, 2016, 36(11): 3737. Peter A. Ajibade. The Intramolecular Spin-Spin Interactions in Ruthenium Complexes of Pyrazole Derivatives[J]. Spectroscopy and Spectral Analysis, 2016, 36(11): 3737.