One‐Pot Synthesis of 3‐Halo‐2‐organochalcogenylbenzo[b]chalcogenophenes from 1‐(2,2‐Dibromovinyl)‐2‐organochalcogenylbenzenes

• Published in: Advanced synthesis & catalysis Vol. 363; no. 10; pp. 2610 - 2618
• Main Authors: Luz, Eduardo Q., Silvério, Gabriel L., Seckler, Diego, Lima, David B., Santana, Francielli S., Barbosa, Ronilson V., Montes D'Oca, Caroline R., Rampon, Daniel S.
• Format: Journal Article
• Language: English
• Published: WEINHEIM Wiley 18.05.2021
• Subjects: 1-(2,2-dibromovinyl)-2-organochalcogenylbenzenes; benzo[b]chalcogenophenes; chalcogenoacetylenes; Chemistry; Chemistry, Applied; Chemistry, Organic; one-pot; Physical Sciences; Science & Technology; one-pot; ELECTROPHILIC CYCLIZATION; ORGANIC SEMICONDUCTORS; chalcogenoacetylenes; 1-(2,2-dibromoyinyl)-2-organochalcogenylbenzenes; benzo[b]chalcogenophenes; FACILE SYNTHESIS; CONJUGATED POLYMERS; DICHALCOGENIDES PROMOTED CYCLIZATION; RADICAL CYCLIZATION; 2,3-DISUBSTITUTED BENZOTHIOPHENES; HETERO-FUSED ANALOGS; OXIDATIVE CYCLIZATION; METAL-FREE
• ISSN: 1615-4150; 1615-4169
• DOI: 10.1002/adsc.202001586

A transition‐metal‐free one‐pot synthesis of 3‐halo‐2‐organochalcogenylbenzo[b]chalcogenophenes has been developed using 1‐(2‐organochalcogenylethynyl)‐2‐butylchalcogenylbenzenes generated in situ from 1‐(2,2‐dibromovinyl)‐2‐organochalcogenylbenzenes and diorganoyl dichalcogenides. By this method, several 2,3‐disubstituted benzo[b]chalcogenophenes were prepared in yields of 48–93%. The mechanistic investigation suggests that the formation of chalcogenoacetylenes containing an adjacent chalcogen atom in the first step of this one‐pot procedure involves acetylide anions formed from 1‐(2,2‐dibromovinyl)‐2‐organochalcogenylbenzenes and mild bases.