Pd/Ligand-Free Synthesis of 2-Alkynylated Pyrano[4,3-d]imidazol-4-ones via One-Pot Cu-Mediated Tandem Sonogashira Coupling/Regioselective 6-endo-dig Oxacyclization Reaction
Herein, we report a one-pot palladium- and ligand-free tandem Sonogashira coupling/regioselective 6-<i>endo</i>-<i>dig</i> oxacyclization reaction of 2,4-diiodo-1-methyl-imidazole-5-carboxylic acid with terminal alkynes mediated by Copper(I). This impressive approach offers a straightforward, practical, and efficient tandem procedure for accessing 2-alkynylated pyrano[4,3-<i>d</i>]imidazol-4-one in moderate to good yields with an exclusive 6-<i>endo</i>-<i>dig</i> oxacyclization. Notably, this cost-effective methodology demonstrates broad substrate compatibility with various commercially available aliphatic and (hetero)aromatic terminal alkynes. Furthermore, DFT studies were performed to elucidate the origin of this regioselective 6-<i>endo</i>-<i>dig</i> oxacyclization reaction.
Authors
- H. Allouchi (ORCID: https://orcid.org/0000-0003-4154-6635)
- Badr Jismy (ORCID: https://orcid.org/0000-0003-1553-0189)
- A. Ayachi (ORCID: https://orcid.org/0000-0002-3537-0170)
- Abdellatif Tikad (ORCID: https://orcid.org/0000-0001-6226-7331)
- Mohamed Abarbri (ORCID: https://orcid.org/0000-0002-6742-1075)
- Marc Blétry (ORCID: https://orcid.org/0000-0003-2509-9847)
- Rafâa Besbes (ORCID: https://orcid.org/0000-0001-5699-6482)
- Vincent Lazeran (ORCID: https://orcid.org/0009-0004-8208-4793)
Institutions
- Tunis University (TN)
- Université de Tours (FR)
- Laboratoire de Chémo-biologie synthétique et thérapeutique (FR)
- Laboratoire des Matériaux Avancés (FR)
- Université Moulay Ismail de Meknes (MA)
- Tunis El Manar University (TN)
Publication Details
- Journal
- Molecules
- Published
- 2025-07-21
- DOI
- https://doi.org/10.3390/molecules30143045
- Primary Topic
- Catalytic C–H Functionalization Methods
- Type
- article
- Field-Weighted Citation Impact
- 0.00