Electric Literature of 14098-44-3, Catalysts are substances that increase the reaction rate of a chemical reaction without being consumed in the process. 14098-44-3, Name is Benzo-15-crown-5, molecular formula is C14H20O5. In a Article£¬once mentioned of 14098-44-3
Solid-state 23Na nuclear magnetic resonance of sodium complexes with crown ethers, cryptands, and naturally occurring antibiotic ionophores: A direct probe to the sodium-binding sites
We report a systematic solid-state 23Na nuclear magnetic resonance study of sodium complexes with crown ethers, cryptands, and naturally occurring antibiotic ionophores. Precise information about 23Na quadrupole coupling constants and chemical shifts was determined from analysis of 23Na magic-angle spinning (MAS) NMR spectra. We found that the experimental 23Na chemical shifts can be related to an empirical parameter that is a function of the atomic valence of the donor ligand, the Na+-ligand distance, and the coordination number (CN) around the Na+ ion of interest. A reasonably good correlation was also observed between the 23Na quadrupole parameters measured in CDCl3 solution and those measured in the solid state, indicating that the cation exchange is slow in CDCl3. In MeOH solution, however, neither 23Na quadrupole parameters nor chemical shifts of the Na-ionophore complexes show correlation with the corresponding solid-state data. Finally, we report the 23Na chemical shift tensor in Na(12C4)2ClO4: delta11 = delta22 = -1 ppm and delta33 = -15 ppm.
The proportionality constant is the rate constant for the particular unimolecular reaction. the reaction rate is directly proportional to the concentration of the reactant. I hope my blog about 14098-44-3 is helpful to your research., Electric Literature of 14098-44-3
Reference£º
Chiral Catalysts,
Chiral catalysts – SlideShare