We report a new and efficient regioselective C3 allylation of indoles using potassium allyltrifluoroborate under PdCl2(dtbpf) catalysis and microwave assisted conditions. The method offers operational simplicity, high regioselectivity, good to excellent yields, and broad substrate compatibility. This study establishes potassium allyltrifluoroborate as a practical allylating reagent for indole functionalization and expands its applicability in synthetic organic chemistry.
References
[1]
Zhang, M., Chen, Q. and Yang, G. (2015) A Review on Recent Developments of Indole-Containing Antiviral Agents. EuropeanJournalofMedicinalChemistry, 89, 421-441. https://doi.org/10.1016/j.ejmech.2014.10.065
[2]
Chadha, N. and Silakari, O. (2017) Indoles as Therapeutics of Interest in Medicinal Chemistry: Bird’s Eye View. EuropeanJournalofMedicinalChemistry, 134, 159-184. https://doi.org/10.1016/j.ejmech.2017.04.003
[3]
Berger, M., Gray, J.A. and Roth, B.L. (2009) The Expanded Biology of Serotonin. AnnualReviewofMedicine, 60, 355-366. https://doi.org/10.1146/annurev.med.60.042307.110802
[4]
Millan, M., Marin, P., Bockaert, J. and Mannourylacour, C. (2008) Signaling at G-Protein-Coupled Serotonin Receptors: Recent Advances and Future Research Directions. TrendsinPharmacologicalSciences, 29, 454-464. https://doi.org/10.1016/j.tips.2008.06.007
Bandini, M. (2013) Recent Advances in the Transition Metal-Catalyzed Functionalization of Indoles at the C3 Position. Organic & Biomolecular Chemistry, 11, Article 5206.
[7]
Trost, B.M. and Quancard, J. (2006) Palladium-Catalyzed Enantioselective C-3 Allylation of 3-Substituted-1H-Indoles Using Trialkylboranes. JournaloftheAmericanChemicalSociety, 128, 6314-6315. https://doi.org/10.1021/ja0608139
[8]
Kimura, M., Futamata, M., Mukai, R. and Tamaru, Y. (2005) Pd-Catalyzed C3-Selective Allylation of Indoles with Allyl Alcohols Promoted by Triethylborane. JournaloftheAmericanChemicalSociety, 127, 4592-4593. https://doi.org/10.1021/ja0501161
[9]
Cacchi, S. and Fabrizi, G. (2005) Synthesis and Functionalization of Indoles through Palladium-Catalyzed Reactions. ChemicalReviews, 105, 2873-2920. https://doi.org/10.1021/cr040639b
[10]
Al-Masum, M. and Liu, K. (2011) A New Organic Transformation by Introducing Crotyl/Allyltrifluoroborates in Cross-Coupling Reaction with Aroyl Chlorides. TetrahedronLetters, 52, 5090-5093. https://doi.org/10.1016/j.tetlet.2011.07.107
[11]
Al-Masum, M. and Alam, S. (2009) Remarkable Regioselectivity in Microwave-Enhanced Palladium-Catalyzed Allylation Reaction Involving Allyltrifluoroborates and Aryl Halides. TetrahedronLetters, 50, 5201-5204. https://doi.org/10.1016/j.tetlet.2009.06.134
[12]
Kundu, M.K. (2025) Regioselective C-Allylation of Indole with Potassium Allyltrfluorobo-Rate in the Presence of Pd-Catalyst. Master’s Thesis, Tennessee State University.
