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Updated: Jun 1, 2026
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Solid-phase Synthesis of [4.4] Spirocyclic Oximes
Published on: February 6, 2019
Concise total synthesis of (±)-cephalotaxine via a transannulation strategy: development of a facile reductive
Wei-Dong Z Li1, Wei-Guo Duo, Cheng-Han Zhuang
1State Key Laboratory of Elemento-organic Chemistry, Nankai University, Tianjin 300071, P. R. China. wdli@nankai.edu.cn
Abstract:
A concise total synthesis of (±)-cephalotaxine (1) has been achieved from dioxolanone derivative 15 via a transannulation strategy. The key transformation is a facile reductive oxy-Nazarov cyclization as illustrated above, involving presumably a tethered 1,2-oxidopentadienyl cation species 7a or 7b, which represents a new variant of the oxy-Nazarov cyclization and constitutes an effective, regio- and stereospecific 5-hydroxy cyclopentenone annulation protocol under mild hydride reduction conditions.
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