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(Thiolan-2-yl)diphenylmethanol Benzyl Ether-Catalyzed Asymmetric Cyclopropanation of Chalcones
Yu-Chen Guo1, Kuei-Wei Chiu2, Rong-Jie Chein2
1Department of Chemistry and Biochemistry, National Chung Cheng University, Chiayi 62102, Taiwan.
Abstract:
We devised a new method for asymmetric cyclopropanation by employing (S)-(thiolan-2-yl)diphenylmethanol benzyl ether as an organocatalyst. Under optimal conditions, an in situ generated sulfur ylide reacts with (E)-chalcones via a Johnson-Corey-Chaykovsky reaction to afford a variety of cyclopropanes in excellent yields and stereoselectivities. This strategy employs low-environmental-risk reaction conditions and reusable catalysts. Hence, it is a green and efficient method for constructing cyclopropane scaffolds.
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