The prevalence of solvent effects in heterogeneous catalysis in condensed media has motivated developing quantitative kinetic, and their interactions with reaction intermediates and transition states. In an article, 108-47-4, name is 2,4-Dimethylpyridine, introducing its new discovery. Application In Synthesis of 2,4-Dimethylpyridine
The reaction of the monoalkyl complex trans-[Pt(DMSO)2Cl(CH3)] with a large variety of heterocyclic nitrogen bases L, in chloroform solution, leads to the formation of uncharged complexes of the type [Pt(DMSO)(L)Cl(CH3)], containing four different groups coordinated to the metal center. Only two out of the three different possible isomers were detected in solution. These two trans(C,N) and cis(C,N) species can be unambiguously identified through 1H NMR spectroscopy. For the trans(C,N) isomers, average values of 2JPtH=75±4 Hz and 3JPtH=36±4 Hz have been observed for the coordinated methyl and DMSO ligands, respectively. In the case of the cis(C,N) isomers, these values increase to 2JPtH=83±2 Hz, and decrease to 3JPtH=26±3 Hz due to the mutual exchange of ligands in trans position to CH3 and DMSO. In the case of bulky asymmetric ligands, such as quinoline, 2-quinolinecarboxaldehyde, 2-methylquinoline, 5-aminoquinoline, 2-phenylpyridine and 2-chloropyridine, slow rotation of the hindered group around the Pt-N bond makes the coordinated DMSO ligand prochiral. NMR experiments have shown that the first reaction product is the trans(C,N) isomer as a consequence of the very fast removal of one DMSO ligand by the nitrogen bases from the starting complex trans-[Pt(DMSO)2Cl(CH3)]. This trans kinetic product undergoes a geometrical conversion into the more stable cis(C,N) isomer through the intermediacy of fast exchanging aqua-species. The rate of isomerization and the relative stability of the two isomers depends essentially on the rate of aquation and on the steric congestion imposed by the new L ligand on the metal.
In conclusion, we affirm that quantitative kinetic descriptions of catalytic behavior continue to serve as an indispensable tool to navigate research efforts intended to model. If you are interested in 108-47-4, you can contact me at any time and look forward to more communication. Application In Synthesis of 2,4-Dimethylpyridine
Reference:
Chiral nitrogen ligands in late transition metal-catalysed asymmetric synthesis—I. Addressing the problem of ligand lability in rhodium-catalysed hydrosilations,
Nitrogen-Containing Ligands for Asymmetric Homogeneous and Heterogeneous Catalysis