Organic Letters
Letter
conditions, we found that the oxidation of the diol 24 with 1.5
equiv of IBX in THF/DMSO (1:1) at room temperature
provided a clean conversion to the spirolactol 25 in 83% yield.25
With the spirolactol 25 in hand, our efforts moved toward
constructing the azacyclononane ring and removing the nosyl,
pivaloyl, and MOM groups to complete the total synthesis of
(+)-sieboldine A (1) (Scheme 5). The denosylation of 25 with
Experimental procedures, characterization for new com-
pounds including NMR spectra and HPLC charts (PDF)
X-ray crystallographic data for 14 (CIF)
AUTHOR INFORMATION
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Corresponding Author
ORCID
Scheme 5. Completion of the Total Synthesis of
(+)-Sieboldine A (1)
Notes
The authors declare no competing financial interest.
ACKNOWLEDGMENTS
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This work was financially supported by JSPS KAKENHI Grant
Nos. 15H02490 (C.M.) and 15K18826 (S.Y.), for which we are
thankful.
REFERENCES
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thiophenolate smoothly proceeded to afford the aminolactol 26
in 90% yield. The N-(methoxymethyloxy)azacyclononane ring
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24
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Org. Lett. XXXX, XXX, XXX−XXX