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Chiral Tertiary Amine Catalyzed Asymmetric [4 + 2] Cyclization of 3-Aroylcoumarines with 2,3-Butadienoate.

ABSTRACT: Coumarins and 2H-pyran derivatives are among the most commonly found structural units in natural products. Therefore, the introduction of 2H-pyran moiety into the coumarin structural unit, i.e., dihydrocoumarin-fused dihydropyranones, is a potentially successful route for the identification of novel bioactive structures, and the synthesis of these structures has attracted continuing research interest. Herein, a chiral tertiary amine catalyzed [4 + 2] cyclization of 3-aroylcoumarines with benzyl 2,3-butadienoate was reported. In the presence of Kumar's 6'-(4-biphenyl)-?-iso-cinchonine, the desired dihydrocoumarin-fused dihydropyranone products could be obtained in up to 97% yield and 90% ee values.

SUBMITTER: Li JL

PROVIDER: S-EPMC7831925 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature

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Chiral Tertiary Amine Catalyzed Asymmetric [4 + 2] Cyclization of 3-Aroylcoumarines with 2,3-Butadienoate.

Li Jun-Lin JL Wang Xiao-Hui XH Sun Jun-Chao JC Peng Yi-Yuan YY Ji Cong-Bin CB Zeng Xing-Ping XP

Molecules (Basel, Switzerland) 20210118 2

Coumarins and 2H-pyran derivatives are among the most commonly found structural units in natural products. Therefore, the introduction of 2H-pyran moiety into the coumarin structural unit, i.e., dihydrocoumarin-fused dihydropyranones, is a potentially successful route for the identification of novel bioactive structures, and the synthesis of these structures has attracted continuing research interest. Herein, a chiral tertiary amine catalyzed [4 + 2] cyclization of 3-aroylcoumarine ...[more]

PMID: 33477686

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