Olefin polymerization catalyst and polymerization process
申请人:Rohn and Haas Company
公开号:US07037987B2
公开(公告)日:2006-05-02
A polymerization catalyst for the polymerization and copolymerization of olefin monomers and the copolymerization of olefin monomers with other monomers selected from, for example, norbornenes and styrenes are disclosed. The polymerization catalysts disclosed contain a metal center selected from Ti, Zr, Hf, Ni and Pd with at least one chelating ligand.
Improved microwave synthesis of unsymmetrical N,N'-diaryl-1,2-aminoethane and imidazolidinium salts as precursors of N-heterocyclic carbenes
作者:Yehia A. Ibrahim、Nouria A. Al-Awadi、Talal F. Al-Azemi、Elizabeth John
DOI:10.1039/c4ra06128d
日期:——
Microwave facilitates the difficult to accomplish lithium aluminium hydride reduction of bis-unsymmetric-diaryloxamides 3 especially for the sterically hindered mesityl derivatives.
Steric factors on unsymmetrical O -hydroxyaryl N -Heterocyclic carbene ligands prevailing the stabilization of single stereoisomer of bis-ligated titanium complexes
作者:Coralie C. Quadri、Ralte Lalrempuia、Nils Åge Frøystein、Karl W. Törnroos、Erwan Le Roux
DOI:10.1016/j.jorganchem.2018.02.018
日期:2018.4
Bis-ligated titanium (IV) metal complexes supported by bidentate unsymmetrical o-hydroxyaryl-substituted N-heterocyclic carbene ligands were synthesized and structurally identified. While the direct addition of the doubly deprotonated bulky imidazolidinium chloride salts [Dipp,4-RNHC-H]Cl (with Dipp = 2,6-diisopropylphenyl, R = H (2-hydroxyphenyl), and R = Me (2-hydroxy-4-methyl-phenyl)) with chloro-titanium