Synthesis of 8-hydroxyquinolines with amino and thioalkyl functionalities at position 4

✍ Scribed by Walaa A. E. Omar; Juha P. Heiskanen; Osmo E. O. Hormi

• Publisher: Journal of Heterocyclic Chemistry
• Year: 2008
• Tongue: English
• Weight: 233 KB
• Volume: 45
• Category: Article
• ISSN: 0022-152X
• DOI: 10.1002/jhet.5570450247

✦ Synopsis

Abstract

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Six 8‐hydroxyquinolines with amino and thioalkyl functionalities at position 4 have been prepared. The synthesis starts with chlorination of the readily available 4‐hydroxy‐8‐tosyloxyquinoline to give 4‐chloro‐8‐tosyloxyquinoline in 94% yield. Treatment of the 4‐chloro‐8‐tosyloxyquinoline with sulphur and nitrogen nucleophiles produces the target 4‐amino and 4‐thioalkyl‐8‐hydroxyquinolines in more than 70% yield. In case of sulphur nucleophiles and pyrrolidine, the removal of the protecting tosyl group at position 8 occurs simultaneously with the substitution of chlorine at position 4.