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Vincent Terrasson Dr. Renata Marcia de Figueiredo Dr. Jean Marc Campagne Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(26):7875-7880
An enantioselective cyclopropanation of α‐substituted α,β‐unsaturated aldehydes with bromomalonate has been successfully developed through a domino Michael/α‐alkylation strategy. The method allows the efficient formation of cyclopropanes bearing a quaternary carbon stereocenter at the α‐position of the aldehydes by using iminium/enamine catalysis and gives a nice extension on the organocatalytic cyclopropanation of bromomalonate and α,β‐unsaturated aldehydes previously reported by other groups. Very good yields (up to 81 %) and enantioselectivities (up to 97 % ee) have been obtained. The optically active cyclopropane derivatives are of high synthetic interest as useful targets for further elaboration into more complex structures. 相似文献
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Catalytic Asymmetric Construction of α‐Quaternary Cyclopentanones and Its Application to the Syntheses of (−)‐1,14‐Herbertenediol and (−)‐Aphanorphine 下载免费PDF全文
Dao‐Yong Zhu Ming‐Hui Xu Prof. Dr. Yong‐Qiang Tu Prof. Dr. Fu‐Min Zhang Prof. Dr. Shao‐Hua Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(44):15502-15505
A novel and efficient strategy to build α‐benzylic quaternary cyclopentanones with excellent enantioselectivities (up to 96 % ee) and high yields (up to 99 % yield) has been developed, and its application demonstrated by the first catalytic asymmetric total synthesis of (?)‐1,14‐herbertenediol and the formal synthesis of (?)‐aphanorphine. 相似文献
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Dr. Carlos Vila Fares Ibrahim Amr Prof. Dr. Gonzalo Blay Prof. Dr. M. Carmen Muñoz Prof. Dr. José R. Pedro 《化学:亚洲杂志》2016,11(10):1532-1536
An efficient one‐pot asymmetric synthesis of pyrazoles bearing a chiral quaternary stereocenter has been developed. Quinine‐derived thiourea catalyzed the enantioselective addition of pyrazolones to isatin‐derived ketimines, providing the corresponding acetylated pyrazoles after in situ treatment with Ac2O/Et3N. The corresponding pyrazoles were afforded in high yields and excellent enantioselectivities. 相似文献
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Nishide K Ozeki M Kunishige H Shigeta Y Patra PK Hagimoto Y Node M 《Angewandte Chemie (International ed. in English)》2003,42(37):4515-4517
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Hayashi Y Urushima T Sakamoto D Torii K Ishikawa H 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(42):11715-11718