Facile regioselective synthesis of 2H-thiopyrano[3,2-c]quinolin-5(6H)-ones by thio-Claisen rearrangement

✍ Scribed by K.C Majumdar; M Ghosh; M Jana; D Saha

• Publisher: Elsevier Science
• Year: 2002
• Tongue: French
• Weight: 132 KB
• Volume: 43
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(02)00194-6

✦ Synopsis

A number of 1-alkyl-4-prop-2-ynylthioquinolin-2(1H)-one derivatives are synthesised by the phase transfer catalyzed reaction of 1-alkyl-4-marcaptoquinolin-2(1H)-ones with different prop-2-ynylic halides. These are then regioselectively cyclised in refluxing chlorobenzene to give hitherto unreported 2H-thiopyrano[3,2-c]quinolin-5(6H)-ones in 85-90% isolable yields.