Ruthenium-catalyzed formal alkyl group transfer: Synthesis of quinolines from nitroarenes and alkylammonium halides

✍ Scribed by Chan Sik Cho; Na Young Lee; Tae-Jeong Kim; Sang Chul Shim

• Publisher: Journal of Heterocyclic Chemistry
• Year: 2004
• Tongue: English
• Weight: 224 KB
• Volume: 41
• Category: Article
• ISSN: 0022-152X
• DOI: 10.1002/jhet.5570410320

✦ Synopsis

Abstract

Nitroarenes are reductively cyclized with an array of tetraalkylammonium halides and trialkylarnmonium chlorides in the presence of a catalytic amount of a ruthenium catalyst along with tin(II) chloride dihydrate at 180° to afford the corresponding quinolines in moderate to good yields. The addition of tin(II) chloride dihydrate is necessary for the effective formation of quinolines and toluene is the solvent of choice. A reaction pathway involving initial reduction of nitroarenes to anilines and conversion of alkylammonium halides to alkylamines, alkyl group transfer from alkylamines to anilines to form an imine, dimerization of imine, and heteroannulation is proposed for this catalytic process.