Abstract
Calcium-catalyzed regioselective synthesis of oxindole-derived 1,5-enynes, followed by cycloisomerization, from readily accessible 3-hydroxy-3-(alkynyl)indolin-2-ones and styrenes in one-pot, under solvent-free conditions is described. This method offers the synthesis of diverse molecules: phenanthridinones, 3-(cyclopentenylidene)indolin-2-ones, and 3-spirocyclic indolin-2-ones are obtained through cascade reactions including cross-dehydrative-coupling, [3,3]-sigmatropic rearrangement, carbocyclization, isomerization, oxidative-ring rearrangement, and Diels-Alder cycloaddition. In addition, this method features atom- and step-economy, broad substrate scope, and high yields. (Figure presented.).
| Original language | English (US) |
|---|---|
| Pages (from-to) | 3068-3075 |
| Number of pages | 8 |
| Journal | Advanced Synthesis and Catalysis |
| Volume | 359 |
| Issue number | 17 |
| DOIs | |
| State | Published - Sep 4 2017 |
| Externally published | Yes |
Bibliographical note
Funding Information:This work is partially supported by SERB (SB/FT/CS-149/2012) and CSIR (02/200/14/EMR-II) India. AP and RD thank Central University of Rajasthan for the fellowships. Authors are grateful to Dr. Gopal K and Mr. Sudhir M for the technical support in solving the crystal structures.
Publisher Copyright:
© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Keywords
- 1,5-enynes
- Diels-Alder reaction
- calcium catalysis
- cycloisomerization
- phenanthridinones
- regioselective