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Updated: Aug 27, 2025
Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
Palladium-Catalyzed Transient Chirality Transfer and Atroposelective C-H Functionalization to Access Quaternary
Lu-Lu Han1, Yu-Ming Cui1, Qin Yang1
1Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education, Key Laboratory of Organosilicon Material Technology of Zhejiang Province, College of Material, Chemistry and Chemical Engineering, Hangzhou Normal University, Hangzhou, Zhejiang, 311121, People's Republic of China.
Abstract:
Although palladium-catalyzed asymmetric C-H functionalization and Heck reactions represents one of the most important synthetic strategies for the construction of quaternary stereocenters, developing the enantioselective version of PdII -catalyzed carbopalladation-initiated cascade reactions still remains a formidable challenge. Herein, an unprecedent enantioselective [3+2] annulation of oxime ethers and alkynes has been developed, providing both spiro and nonspiro indenes bearing all-carbon quaternary stereocenters in good yields (up to 98 %) with excellent enantioselectivities (up to >99 % ee). This annulation is accomplished by merging the PdII -catalyzed atroposelective C-H activation/double carbopalladation and the transient axial-to-central chirality transfer process, constituting the first successful example of catalytic chirality transfer strategy involving axially chiral styrene intermediate.
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