Über die Chemie des Vitamins E. 1. Mitteilung. Die Umkehrung der Konfiguration am Kohlenstoffatom 2 von natürlichem (2 R, 4′ R, 8′ R)-α-Tocopherol

✍ Scribed by P. Schudel; H. Mayer; J. Metzger; R. Rüegg; O. Isler

• Publisher: John Wiley and Sons
• Year: 1963
• Tongue: German
• Weight: 723 KB
• Volume: 46
• Category: Article
• ISSN: 0018-019X
• DOI: 10.1002/hlca.19630460134

✦ Synopsis

Abstract

(2 S, 4′R, 8′R)‐α‐Tocopherol with unnatural configuration at C‐2 is prepared by oxidation of natural, so called d‐α‐tocopherol (I), which has the (2__R__, 4′R, 8′R)‐configuration, to α‐tocopherylquinone (II), followed by recyclization of the corresponding α‐tocopherylhydroquinone (III). Experiments showed that the configuration of carbon atom 2 of natural α‐tocopherol is retained during the ferric chloride oxidation (I →II) and is predominantly inverted by zinc chloride cyclization of α‐tocopherylhydroquinone (III).