In this communication, a chiral squaramide-catalyzed asymmetric dearomative tandem annulation reaction of unmodified Morita-Baylis-Hillman alcohols with azomethine imines has been achieved through a kinetic resolution of MBH alcohols under mild conditions, giving pharmaceutically interesting functionalized hetero-bicyclo[3.3.1]nonane derivatives in good to excellent yields with excellent enantioselectivities.
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A quinine-squaramide catalyzed enantioselective vinylogous Mannich reaction between benzothiazolimines and γ-butenolides for efficient preparation of chiral -benzothiazole butyrolactones.
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Key Laboratory of Asymmetric Synthesis and Chirotechnology of Sichuan Province, Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, China.
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