ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Synthesis of 2-[3-(trifluoromethyl)phenyl]furo[3,2-c]pyridine derivatives

Ivana Bradiaková, Tatiana Ďurčeková, Naďa Prónayová, Anton Gatial, and Alžbeta Krutošíková

Department of Chemistry, Faculty of Natural Sciences, University of St. Cyril and Methodius, SK-917 01 Trnava, Slovakia

E-mail: alzbeta.krutosikova@ucm.sk

Received: 29 October 2008  Revised: 21 January 2009  Accepted: 5 February 2009

Abstract: 2-[3-(Trifluoromethyl)phenyl]-4,5-dihydrofuro[3,2-c]pyridin-4-one (I) was prepared by a three-step synthesis. Its reaction with phosphorus sulfide rendered thione II which was methylated to 2-[3-(Trifluoromethyl)phenyl]-4-methylsulfanylfuro[3,2-c]pyridine (III). 5-Methyl-2-[3-(trifluoromethyl)phenyl]-4,5-dihydrofuro[3,2-c]pyridin-4-one (IV) was obtained by the reaction of I with methyl iodide in PTC conditions. The chlorine atom in derivate V was replaced with heterocyclic secondary amines via nucleophilic substitution and 4-substituted furopyridines VIa and VIb were thus prepared. 2-[3-(Trifluoromethyl)phenyl]furo[3,2-c]pyridine-4-carboxylic acid (VII) was obtained by hydrolysis of the corresponding carbonitrile Va.

Keywords: 4-substituted 2-[3-(trifluoromethyl)phenyl]furo[3,2-c]pyridines - nucleophilic substitution

Full paper is available at www.springerlink.com.

DOI: 10.2478/s11696-009-0052-4

Chemical Papers 63 (5) 586–591 (2009)