Reactions catalyzed within inorganic and organic materials and at electrochemical interfaces commonly occur , causing turnover rates to depend strongly on interfacial structure and composition, In an article, author is de Oliveira, L. L., once mentioned the application of 10500-57-9, Safety of 5,6,7,8-Tetrahydroquinoline, Name is 5,6,7,8-Tetrahydroquinoline, molecular weight is 133.19, category is quinoxaline. Now introduce a scientific discovery about this category.
Chromium(III) complexes based on phenoxy-imine ligands with pendant N- and O-donor groups as precatalysts for ethylene oligomerization: synthesis, characterization, and DFT studies
Chromium complexes of general formula [Cr{ZNO}(THF)Cl-2] [2a, ZNO = C9H6N-8-(N=CH)-2,4-tert-butyl-2-(OC6H2); 2b, ZNO = Ph(NH)-C2H4-(N=CH) 2,4-tert-butyl-2-(OC6H2); 2c, ZNO = 2 MeO-Ph-CH2-(N=CH)-2,4-tert-butyl-2-(OC6H2); 2d, ZNO = 2-PhO-Ph-(N=CH)-2,4-tert-butyl-2-(OC6H2); 2e, ZNO = PhO-C2H4-(N=CH)-2,4-tert-butyl-2-(OC6H2)] and the bis(ligand) complex [Cr{C9H6N-8-NH2}(2)Cl-2]Cl (4) were synthetized and characterized by elemental analysis, IR spectroscopy, and by X-ray crystallography for 4. In the solid state, 4 is monomeric with two 8-amino-quinoline acting as bidentate ligands and two chloride ligands in cis position. The DFT calculations showed slightly higher HOMO energy for 2d. In addition, the energy levels of the LUMO are slightly influenced by pendant O- and N-donor group. Particularly, the LUMOs for complexes 2a and 2d show a small contribution from Cr and Cl atoms as compared to other chromium complexes (2b, 2c and 2e), and the orbitals are almost entirely delocalized over the phenoxy-imine unit. Upon activation with methylaluminoxane (MAO), chromium precatalysts 2a-2e showed good activity in ethylene oligomerization (TOF = 22.0 – 52.7 x 10(3) (mol ethylene)(mol Cr)(-1) .h(-1) at 80 degrees C) with Schultz-Flory distribution of oligomers (KC4-C10 approximate to 0.92), and production of polymer varying from 2.9 to 22.3 wt.%. The catalytic performance is mainly controlled by electronic effects at the phenoxyimine ligands. The bis(ligand) chromium complex 4 showed good activity in ethylene oligomerization (TOF = 39,400 (mol ethylene)(mol Cr)(-1) h(-1)), producing mostly oligomers (95.2 wt% of total products) with high selectivity for alpha-olefins. The highest activity among the six precatalysts screened was reached with 2c (TOF = 52,700 mol(ethylene).mol(Cr)(-1) h(-1)). (C) 2021 Elsevier B.V. All rights reserved.
But sometimes, even after several years of basic chemistry education, it is not easy to form a clear picture on how they govern reactivity! 10500-57-9, you can contact me at any time and look forward to more communication. Safety of 5,6,7,8-Tetrahydroquinoline.
Reference:
Quinoline – Wikipedia,
,Quinoline | C9H7N – PubChem