Enantioselective Total Synthesis of (−)‐Blennolide A |
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Authors: | Prof. Dr. Lutz F. Tietze Dr. Ling Ma Johannes R. Reiner Stefan Jackenkroll Sven Heidemann |
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Affiliation: | Institute of Organic and Biomolecular Chemistry, Georg‐August‐University G?ttingen, Tammannstrasse 2, 37077 G?ttingen (Germany), Fax: (+49)?551‐39‐9476 |
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Abstract: | Blennolide A can be synthesized through an enantioselective domino‐Wacker/carbonylation/methoxylation reaction of 7 a with 96 % ee and an enantioselective Wacker oxidation of 7 b with 89 % ee. Further transformations led to the α,β‐unsaturated ester (E)‐ 17 , which was subjected to a highly selective Michael addition, introducing a methyl group to give 18 a . After a threefold oxidation and an intramolecular acylation, the tetrahydroxanthenone 4 was obtained, which could be transformed into (?)‐blennolide A (ent‐ 1 ) in a few steps. |
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Keywords: | domino‐reactions Michael reaction natural product palladium Wacker oxidation xanthenone |
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