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Enantioselective Michael Addition of Cyclic ?-Diones to ?,?-Unsaturated Enones Catalyzed by Quinine-Based Organocatalysts.

ABSTRACT: An enantioselective (52-98% ee) Michael addition between cyclic ?-diones and ?,?-unsaturated enones was established in the presence of quinine-based primary amine or squaramide. A variety of cinnamones were smoothly converted into the desired 3,4-dihydropyrans in moderate to high yields (63-99%). Chalcones were also suitable acceptors and gave rise to the expected adducts in satisfactory yields (31-99%). The resulting adducts readily underwent further modification to form fused 4H-pyran or 2,3-dihydrofuran.

SUBMITTER: Wang Q

PROVIDER: S-EPMC6152274 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature

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Enantioselective Michael Addition of Cyclic β-Diones to α,β-Unsaturated Enones Catalyzed by Quinine-Based Organocatalysts.

Wang Qingqing Q Wang Wei W Ye Ling L Yang Xuejun X Li Xinying X Zhao Zhigang Z Li Xuefeng X

Molecules (Basel, Switzerland) 20170630 7

An enantioselective (52-98% ee) Michael addition between cyclic β-diones and α,β-unsaturated enones was established in the presence of quinine-based primary amine or squaramide. A variety of cinnamones were smoothly converted into the desired 3,4-dihydropyrans in moderate to high yields (63-99%). Chalcones were also suitable acceptors and gave rise to the expected adducts in satisfactory yields (31-99%). The resulting adducts readily underwent further modification to form fused 4H-pyran or 2,3-d ...[more]

PMID: 28665357

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