ISSN:
0018-019X
Schlagwort(e):
Chemistry
;
Organic Chemistry
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Chemie und Pharmazie
Notizen:
Starting from the readily available, optically active (4R)-hydroxy-2,2,6-trimethylcyclohexanone (2), a new technical synthesis of (3R,3′R)-zeaxanthin is described. According to a completely new C9+C2+C4 = C15 scheme, the ketone 2 was protected, ethynylated with Li-acetylide, and the C11-intermediate 6 was acetylated, followed by dehydration. The product 10 was protected, deprotonated, and subsequently reacted with methyl vinyl ketone to provide the C15-propargylate 13. Reduction in situ of 13 with Vitride yielded the olefinic C15-alcohol 11 which was transformed into the known C15-Wittig salt 3. A double Wittig reaction of this salt with the C10-dialdehyde 4 afforded nature-identical zeaxanthin (1).
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/hlca.19900730412
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