Synthesis of Well-Defined Poly(2-alkoxypyridine-3,5-diyl) via Ni-Catalyst-Transfer Condensation Polymerization was written by Nanashima, Yutaka;Yokoyama, Akihiro;Yokozawa, Tsutomu. And the article was included in Macromolecules (Washington, DC, United States) in 2012.Category: pyridine-derivatives This article mentions the following:
Ni-catalyzed Kumada-Tamao coupling polymerization of 5-bromo-3-chloromagnesio-2-(2-(2-methoxyethoxy)ethoxy)pyridine (1) was investigated. Monomer 1, which was obtained quant. by treatment of the corresponding bromoiodopyridine 3 with 1.0 equiv of iPrMgCl at 0°, was polymerized with Ni(dppp)Cl2 (dppp = 1,3-bis(diphenylphospino)propane) in the presence of 2.0 equiv of LiCl in THF at room temperature to yield poly(2-(2-(2-methoxyethoxy)ethoxy)pyridine-3,5-diyl) (m-PMEEOPy) with narrow polydispersity. The Mn value was controlled by the feed ratio of the monomer precursor 3 to Ni(dppp)Cl2. MALDI-TOF mass spectra showed that m-PMEEOPy uniformly had a bromine atom at one end and a hydrogen atom at the other. Both end groups could be converted to aryl groups by addition of an excess of aryl magnesium chloride to the reaction mixture after completion of the polymerization These results indicate that the polymerization of 1 with Ni(dppp)Cl2 involves the intramol. catalyst-transfer polymerization mechanism. In the experiment, the researchers used many compounds, for example, 3,5-Dibromo-2-hydroxypyridine (cas: 13472-81-6Category: pyridine-derivatives).
3,5-Dibromo-2-hydroxypyridine (cas: 13472-81-6) belongs to pyridine derivatives. The ring atoms in the pyridine molecule are sp2-hybridized. The nitrogen is involved in the π-bonding aromatic system using its unhybridized p orbital. The lone pair is in an sp2 orbital, projecting outward from the ring in the same plane as the σ bonds. Pyridine derivatives are also useful as small-molecule α-helix mimetics that inhibit protein-protein interactions, as well as functionally selective GABA ligands.Category: pyridine-derivatives