Synthesis 2006(23): 3987-3996  
DOI: 10.1055/s-2006-950338
PAPER
© Georg Thieme Verlag Stuttgart · New York

Synthesis of Functionalized Pyridines by Substitution of Hetarenium-Activated­ Pentachloropyridine with Bisnucleophiles

Andreas Schmidt*a, Thorsten Mordhorsta, Martin Niegerb
a Clausthal University of Technology, Institute of Organic Chemistry, Leibnizstraße 6, 38678 Clausthal-Zellerfeld, Germany
Fax: +49(5323)722858; e-Mail: schmidt@ioc.tu-clausthal.de;
b University of Bonn, Institute of Inorganic Chemistry, Gerhard-Domagk-Straße 1, 53121 Bonn, Germany
Further Information

Publication History

Received 23 June 2006
Publication Date:
02 November 2006 (online)

Abstract

Pyridines, acting as heteroaromatic N-nucleophiles, 4-aminopyridine as an N,N-bisnucleophile, and 3,4-diaminopyridine as an N,N,N-trisnucleophile, all reacted with 4-(dimethylamino)-1-(2,3,5,6-tetrachloropyridin-4-yl)pyridinium chloride to give tris­pyridinio-substituted 3,5-dichloropyridines. Reaction of the same pyridinium chloride with O,O-bisnucleophiles such as 1,3-propanediol, hydroquinone, and resorcine, or the O,O,O-nucleophile phloroglucine, formed new Cl2,Cl3,O4,Cl5,Cl6 and O2,Cl3,O4,Cl5,Cl6-substituted pyridines. S,O-Bisnucleophiles, such as 2-sulfanylethanol or 3-sulfanylpropionic acid gave the corresponding S-substituted pyridines (x-ray analysis). The (pyridin-4-yl)propionic acid was converted into bis(pyridinio)pyridine-4-thiol, an example of the rare class of N2,Cl3,S4,Cl5,N6-substituted pyridines.