Flavonoids—38: Reaction of 2'-hydroxychalcone dibromides and -α-bromochalcones with azide ion

✍ Scribed by Tamás Patonay; Rezsö Bognár; György Litkei

• Book ID: 104203069
• Publisher: Elsevier Science
• Year: 1984
• Tongue: French
• Weight: 616 KB
• Volume: 40
• Category: Article
• ISSN: 0040-4020
• DOI: 10.1016/s0040-4020(01)83509-2

✦ Synopsis

The reaction of 2'-hydroxychalcone dibromides 1 or a-bromo-2'-hydroxychalcones 15 with sodium axide resulted in a mixture of a-axido-2'-hydroxychalcones 2, 3-aryl-S-(2-hydroxyphenyl)isoxaxoles 3, flavones 4, aurones 5 and 4-aryl-5-(2-hydroxybenxoyl)-1,2,3-triaxoles 6. The product ratio was strongly influenced by the character of the substituent at position C-4. Similar results were obtained with 2'-benxyloxy-4-nitrochalcone dibromide (10) and 2'-benxyloxy-a-bromo-4-nitrochalcone (17). The mechanism of the transformation of chalcone dibromides into the products via an a-bromochalcone intermediate is discussed.