Diastereoselective construction of cis 2,6-disubstituted tetrahydropyran rings via In(OTf)3-catalyzed intramolecular 2,5-oxonium-ene cyclization: synthetic studies towards the total synthesis of zampanolide and dactylolide

✍ Scribed by Teck-Peng Loh; Jian-Ying Yang; Li-Chun Feng; Yan Zhou

• Publisher: Elsevier Science
• Year: 2002
• Tongue: French
• Weight: 129 KB
• Volume: 43
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(02)01666-0

✦ Synopsis

Diastereoselective construction of 2,6-disubstituted tetrahydropyrans with an exocyclic double bond was achieved via the In(OTf) 3 -catalyzed intramolecular 2,5-oxonium-ene cyclization. Its application was further demonstrated by the synthesis of a common intermediate for both zampanolide and dactylolide, fragment I, with a total yield of 42% in three steps starting from (2E)-3-bromobut-2-enal.