3-Trifluoromethanesulfonyloxy-4,7-dihydropyrazolo[1,5-a]pyridine via Ring-Closing Metathesis: Synthesis and Transformation to Withasomnine Homologs
- 1 January 2021
- journal article
- research article
- Published by The Japan Institute of Heterocyclic Chemistry in HETEROCYCLES
- Vol. 103 (1), 284-299
- https://doi.org/10.3987/com-20-s(k)13
Abstract
3-Trifluoromethanesulfonyloxy-4,7-dihydropyrazolo[1,5-alpha]pyridine (9) was successfully synthesized from the starting material, pyrazole, via a sequence of reactions containing ring-closing metathesis as a key step. Suzuki-Miyaura coupling of 9 with various arylboronic acids, followed by oxidation or hydrogenation, readily afforded pyrazolo[1,5-alpha] pyridines (11) or 3-aryl-4,5,6,7-tetrahydropyrazolo[1,5-alpha]pyridines (12), respectively. Compounds 12 were found to be withasomnine homologs.Keywords
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