Lewis Base Catalyzed [4+2] Annulation of
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Dipl.-Chem. Heiko Dรผckert; Dr. Vivek Khedkar; Prof.โ
Dr. Herbert Waldmann; Dr. Ka
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Article
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2011
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John Wiley and Sons
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English
โ 300 KB
## Abstract Lewis base catalyzed [4+2] annulation reactions between electronโdeficient chromone oxaโ and azadienes and acetylene carboxylates provide tricyclic benzopyrones inspired by natural products. An asymmetric synthesis of the tricyclic benzopyrones was developed by using modified cinchona a