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Novel ether-ring transformation via a phenonium ion

✍ Scribed by Shinji Nagumo; Yusuke Ishii; Yo-ichiro Kakimoto; Norio Kawahara

Publisher: Elsevier Science
Year: 2002
Tongue: French
Weight: 170 KB
Volume: 43
Category: Article
ISSN: 0040-4039
DOI: 10.1016/s0040-4039(02)01009-2

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✦ Synopsis

Upon treatment with CF 3 COOH at 70°C, trisubstituted-tetrahydropyrans, which were stereoselectively prepared from d-lactones, were found to be converted into the corresponding 2,5-disubstituted-tetrahydrofurans stereospecifically via a phenonium ion. Furthermore, the stereocontrolled formal synthesis of pamamycin 607 was achieved based on the ether-ring transformation.

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