Cascade spirocyclization or cyclization of aldehyde hydrazone derivatives with polychloromethane
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Updated: Nov 10, 2026
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Solid-phase Synthesis of [4.4] Spirocyclic Oximes
Published on: February 6, 2019
Lijun Tu1, Qinqin Yan1, Haiyang Sun1
1State Key Laboratory of New Pharmaceutical Preparations and Excipients, Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education, Key Laboratory of Chemical Biology of Hebei Province, College of Chemistry and Materials Science, Hebei University, Baoding, Hebei, 071002, P. R. China. yanqin_9397@126.com.
Abstract:
The smooth free-radical polychloromethylation spirocyclization or cyclization of BCB-tethered or N-acryloyl aldehyde hydrazones was developed, affording diverse polychloromethylated 6,7-diazaspiro[3.4]oct-7-en-5-ones or pyrazolones. Single-crystal X-ray diffraction data confirmed that the spirocyclic products were trans and cis isomers. Two cascade systems could be scaled up to 1 mmol and tolerated some complex substrates well. Finally, plausible spirocyclization or cyclization pathways were proposed based on mechanistic studies.
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