Regioregulated Syntheses of Poly(aminopyridine)s by Pd-catalyzed Amination Reaction

✍ Scribed by Junpei Kuwabara; Hironori Mori; Takuya Teratani; Munetaka Akita; Takaki Kanbara

• Book ID: 102492673
• Publisher: John Wiley and Sons
• Year: 2009
• Tongue: English
• Weight: 168 KB
• Volume: 30
• Category: Article
• ISSN: 1022-1336
• DOI: 10.1002/marc.200900033

✦ Synopsis

Abstract

Regioregulated poly(aminopyridine)s were synthesized by a Pd‐catalyzed CN coupling reaction. The polymerization using Pd(0) and a bulky monodentate phosphine ligand distinctively produced the para‐linked and meta‐linked poly(aminopyridine)s, without the need for a protection process. The regioregularity of the polymer was confirmed by ^1^H NMR spectroscopy. Model reactions were studied to evaluate the possibility of crosslinkage in the polymer. A large difference in reactivity was observed between 5‐amino‐2‐bromopyridine and 2‐amino‐5‐bromopyridine, which should have afforded same product. Density functional theory (DFT) calculations indicated that electron densities of the Br‐bound carbon atom and the pyridine‐nitrogen atom determine the reactivity of the monomers.

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