Hansen, Helge-Boj; Wadepohl, Hubert; Enders, Markus published their research in Chemistry – A European Journal on August 2 ,2021. The article was titled 《The Stronger the Better: Donor Substituents Push Catalytic Activity of Molecular Chromium Olefin Polymerization Catalysts》.Computed Properties of C6H8N2 The article contains the following contents:
The donor strength of bifunctional pyridine-cyclopentadienyl ligands was altered systematically by the introduction of donating groups in the para-position of the pyridine. In the resulting chromium complexes an almost linear correlation between donor strength and the nitrogen-chromium distance as well as the electronic absorption maximum is exptl. observed The connection of electron-donating groups in the ligand backbone leads to an efficient transfer of the electronic influences to the catalytically active metal center without restricting it through steric effects. Therefore, catalytic olefin polymerization activity, which is already very high for the previously studied catalysts, increase considerably by attaching para-amino groups to the chelating pyridine or quinoline, resp. Combining electron-rich indenyl ligands with para-amino substituted pyridines lead to the highest catalytic activities observed so far for this class of organo chromium olefin polymerization catalysts. The resulting polymers are of ultra-high mol. weight and the ability of the catalysts to incorporate co-monomers is also very high. In the experiment, the researchers used 4-Amino-2-picoline(cas: 18437-58-6Computed Properties of C6H8N2)
4-Amino-2-picoline(cas: 18437-58-6) belongs to anime. Amines characteristically form salts with acids; a hydrogen ion, H+, adds to the nitrogen. With the strong mineral acids (e.g., H2SO4, HNO3, and HCl), the reaction is vigorous. Salt formation is instantly reversed by strong bases such as NaOH. Neutral electrophiles (compounds attracted to regions of negative charge) also react with amines; alkyl halides (R′X) and analogous alkylating agents are important examples of electrophilic reagents.Computed Properties of C6H8N2