Dehalogenation of o-dihalogen substituted arenes and α,α′-dihalogen substituted o-xylenes with lanthanum metal

✍ Scribed by Yutaka Nishiyama; Hiroshi Kawabata; Toshiki Nishino; Kouji Hashimoto; Noboru Sonoda

• Book ID: 104205611
• Publisher: Elsevier Science
• Year: 2003
• Tongue: French
• Weight: 208 KB
• Volume: 59
• Category: Article
• ISSN: 0040-4020
• DOI: 10.1016/s0040-4020(03)01027-5

✦ Synopsis

It was found that lanthanum metal caused the dehalogenation of o-dihalogen substituted arenes and a,a 0 -dihalogen substituted o-xylenes to generate the corresponding benzynes and o-quinodimethanes. When o-dihalogen substituted arenes were allowed to react with lanthanum metal in the presence of dienes, the Diels -Alder products between benzyne and dienes were formed in moderate to good yields. Similarly, the Diels -Alder adducts of o-quinodimethane with dienophiles were obtained, in the reaction of a,a 0 -dibromo-o-xylenes with lanthanum metal in the presence of dienophiles.