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Dibenzocycloheptanones construction through a removable P-centered radical: synthesis of allocolchicine analogues.

ABSTRACT: Dibenzocycloheptanones containing a tricyclic 6-7-6-system are present in numerous biologically active natural molecules. However, the simple and efficient preparation of derivatives containing a dibenzocycloheptanone scaffold remains difficult to date. Herein, we report a versatile strategy for the construction of these challenging seven-membered rings using a 7-endo-trig cyclization which is initiated by a phosphorus-centered radical. This approach provides a step-economical regime for the facile assembly of a wide range of phosphorylated dibenzocycloheptanones. Remarkably, we also have devised a traceless addition/exchange strategy for the preparation of dephosphorylated products at room temperature with excellent yields. Therefore, this protocol allows for the concise synthesis of biorelevant allocochicine derivatives.

SUBMITTER: Zhang Y

PROVIDER: S-EPMC8654019 | biostudies-literature | 2021 Dec

REPOSITORIES: biostudies-literature

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Dibenzocycloheptanones construction through a removable <i>P</i>-centered radical: synthesis of allocolchicine analogues.

Zhang Yan Y Cai Zhenzhi Z Struwe Julia J Ma Chanchan C Zeng Wangyu W Liao Xinyi X Xu Min M Ackermann Lutz L

Chemical science 20211109 47

Dibenzocycloheptanones containing a tricyclic 6-7-6-system are present in numerous biologically active natural molecules. However, the simple and efficient preparation of derivatives containing a dibenzocycloheptanone scaffold remains difficult to date. Herein, we report a versatile strategy for the construction of these challenging seven-membered rings using a 7-<i>endo</i>-trig cyclization which is initiated by a phosphorus-centered radical. This approach provides a step-economical regime for ...[more]

PMID: 35003604

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