Solid-State NMR of a Paramagnetic DIAD-FeII Catalyst: Sensitivity, Resolution Enhancement, and Structure-Based Assignments
摘要:
A general protocol for the structural characterization of paramagnetic molecular solids using solid-state NMR is provided and illustrated by the characterization of a high-spin FeII catalyst precursor. We show how good NMR performance can be obtained on a molecular powder sample at natural abundance by using very fast (> 30 kHz) magic angle spinning (MAS), even though the individual NMR resonances have highly anisotropic shifts and very short relaxation times. The results include the optimization of broadband heteronuclear (proton-carbon) recoupling sequences for polarization transfer; the observation of single or multiple quantum correlation spectra between coupled spins as a tool for removing the inhomogeneous bulk magnetic susceptibility (BMS) broadening; and the combination of NMR experiments and density functional theory calculations, to yield assignments.
Syntheses and structures of the cobalt, nickel, and zinc complexes with 1,4-diaza-1,3-butadiene ligands
作者:P. A. Petrov、T. S. Sukhikh、D. A. Piryazev、A. V. Virovets、S. N. Konchenko
DOI:10.1134/s1070328413010089
日期:2013.1
Several cobalt(II), nickel(II), and zinc(II) complexes with a series of ligands of the 1,4-diaza-1,3-butadiene type bearing aryl (2,6-di-iso-propylphenyl, mesityl) and alkyl (tert-butyl, iso-propyl) substituents at the nitrogen atoms are synthesized. The obtained complexes are characterized by X-ray structure analysis, IR spectroscopy, and elemental analysis.
A new zinc–zinc-bonded compound with a dianionic α-diimine ligand: synthesis and structure of [Na(THF)<sub>2</sub>]<sub>2</sub>·[LZn–ZnL] (L = [(2,6-iPr<sub>2</sub>C<sub>6</sub>H<sub>3</sub>)N(Me)C]<sub>2</sub><sup>2−</sup>)
作者:Xiao-Juan Yang、Jie Yu、Yanyan Liu、Yaoming Xie、Henry F. Schaefer、Yongmin Liang、Biao Wu
DOI:10.1039/b703200e
日期:——
The synthesis and structure of a ZnâZn-bonded compound supported by a doubly reduced α-diimine ligand, [Na(THF)2]2·[LZnâZnL] (L = [(2,6-iPr2C6H3)N(Me)C]22â) are reported, with a ZnâZn bond length of 2.399(1) à .