Synthesis of novel azonia Helicenes containing terminal thiophene rings

✍ Scribed by Kiyoshi Sato; Takamichi Yamagishi; Sadao Arai

• Publisher: Journal of Heterocyclic Chemistry
• Year: 2000
• Tongue: English
• Weight: 424 KB
• Volume: 37
• Category: Article
• ISSN: 0022-152X
• DOI: 10.1002/jhet.5570370453

✦ Synopsis

Abstract

The Knoevenagel condensation of the 9‐methyl derivatives of thieno[3,2‐a]‐ and thieno[2,3‐a]‐quinolizinium salts (2b and 3b) with appropriate arylaldehydes yielded 9‐(arylvinyl)thieno[3,2‐a]‐ and 9‐(arylvinyl)thieno[2,3‐a]quinolizinium salts (4a‐c and 5a‐c), respectively, which underwent photocyclization to give a series of novel hetero[5]helicenes (6a,b and 7a‐d) containing quinolizinium and thiophene rings.