A scalable and diversity-oriented synthesis of (±)-paeoveitols

Abstract

Gram scale synthesis of (±)-paeoveitol, a nor-diterpene harboring an unusual benzofuran stitched benzopyran 6/5/6/6 tetracyclic ring system, and its analogues, emanating from bench-top reagents is reported. Scandium triflate-mediated inverse electron demand [4 + 2] cycloaddition reaction between pre-synthesized paeoveitol-D analogue (dienophile) and ortho-quinone methide precursor (diene), both resulting from the same starting material delivered (±)-paeoveitol in decent yield. Fine tuning of the synthetic strategy not only helped to procure scalable quantities of natural product but also provided ample scope to look for the diversity-oriented synthesis of its analogues.

Graphical Abstract

Keywords:

• (±)-paeoveitol
• paeoveitol-D
• IEDDAR
• ortho-quinone methide
• diversity-oriented synthesis

Acknowledgments

S. R. thanks School of Chemistry, UoH and Prof. G. Mehta for hosting him in his group.

Disclosure statement

The authors declare that they have no known competing financial interests or personal relationships that could appear to influence the work reported in this paper.

Data availability statement

Full experimental details including ¹H and ¹³C NMR spectra can be found in the Supplementary Content of this article.

Additional information

Funding

BAB acknowledges the financial support from Science and Engineering Research Board [CRG/2019/005179]. IIIM publication No. IIM/IPR/00279.