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Carbocation Lewis Acid TrBF4-Catalyzed 1,2-Hydride Migration: Approaches to (Z)-α,β-Unsaturated Esters and α-Branched β-Ketocarbonyls

Wansong Shang, Depeng Duan, Yongjun Liu* and Jian Lv*

*College of Chemistry and Molecular Engineering, Qingdao University of Science & Technology, Qingdao 266042, China, Email:,

W. Shang, D. Duan, Y. Liu, J. Lv, Org. Lett., 2019, 21, 8013-8017.

DOI: 10.1021/acs.orglett.9b03005

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The carbocation Lewis acid tritylium tetrafluoroborate (TrBF4) catalyzes a 1,2-hydride migration of α-alkyldiazoacetates to provide (Z)-α,β-unsaturated esters in good yields and with high regioselectivities. Using the same catalytic system, in situ-generated cross-coupling adducts of aldehydes and α-alkyldiazoacetates give α-branched β-ketocarbonyls.

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Key Words

α,β-unsaturated esters

ID: J54-Y2019