A Green Approach: Eosin Y-Facilitated VisibleLight Preparation of a Functionalized 1,2,3- Triazole Compound
Main Article Content
Abstract
A key goal of contemporary organic chemistry is developing environmentally acceptable, sustainable methods for synthesising nitrogen-containing heterocycles. Because of their broad biological activities and medicinal chemistry applications, 1,2,3-triazoles have garnered considerable attention among these heterocycles. In this study, we developed a visible-light-induced process to synthesise (4-hexyl-2H-1,2,3-triazole-2-yl) methanol using Eosin Y as an organic photocatalyst. The reaction is a threecomponent coupling of formaldehyde, sodium azide, and terminal alkynes that occurs under visible light at ambient temperature. Eosin Y (5 mol%) in an H2O/DMSO (1:1) solvent system under blue LED irradiation yields the required triazole derivatives in good yield when reaction parameters are optimised. Control studies validated the crucial roles of visible light and the photocatalyst in the reaction. Without a transition-metal catalyst, the transformation proceeds under mild conditions, demonstrating the protocol’s environmental friendliness. We propose a viable photoredox process that generates reactive intermediates and activates Eosin Y under visible light. This process offers a straightforward, effective, and environmentally friendly way to create functionalized 1,2,3-triazole derivatives.
Downloads
Article Details
Section

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
How to Cite
References
Hassani, I., Rouzi, K., Hassani, A., Karrouchi, K., & Ansar, M. (2024). Recent Developments Towards the Synthesis of Triazole Derivatives: A Review. Organics. DOI: 10.3390/org5040024.
Matin, M., Matin, P., Rahman, M., Hadda, B., Almalki, F., Mahmud, S., Ghoneim, M., Alruwaily, M., & Alshehri, S. (2022). Triazoles and Their Derivatives: Chemistry, Synthesis, and Therapeutic Applications. Frontiers in Molecular Biosciences, 9.
DOI: 10.3389/fmolb.2022.864286.
Bozorov, K., Zhao, J., & Aisa, H. (2019). 1,2,3-Triazole-containing hybrids as leads in medicinal chemistry: A recent overview. Bioorganic & Medicinal Chemistry, 27, 3511 - 3531. DOI: 10.1016/j.bmc.2019.07.005.
Kumar, S., Sharma, B., Mehra, V., & Kumar, V. (2020). Recent accomplishments on the synthetic/biological facets of pharmacologically active 1H-1,2,3-triazoles. European Journal of Medicinal Chemistry, 212, 113069. DOI: 10.1016/j.ejmech.2020.113069.
Bonandi, E., Christodoulou, M., Fumagalli, G., Perdicchia, D., Rastelli, G., & Passarella, D. (2017). The 1,2,3-triazole ring as a bioisostere in medicinal chemistry. Drug Discovery Today, 22 (10), 1572- 1581. DOI: 10.1016/j.drudis.2017.05.014.
Mishra, K. (2025). 1,5-Disubstituted 1,2,3-triazoles: Molecular scaffolds for medicinal chemistry and biomolecular mimetics—European Journal of Medicinal Chemistry, 291, 117614. DOI: 10.1016/j.ejmech.2025.117614.
Lengerli, D., İbiş, K., Nural, Y., & Banoglu, E. (2022). The 1,2,3-triazole ‘all-in-one’ ring system in drug discovery: a good bioisostere, a good pharmacophore, a good linker, and a versatile synthetic tool. Expert Opinion on Drug Discovery, 17, 1209 - 1236.
DOI: 10.1080/17460441.2022.2129613.
Kasana, S., Nigam, V., Singh, S., Kurmi, B., & Patel, P. (2024). A New Insight into the Huisgen Reaction: Heterogeneous Copper-Catalyzed Azide‐Alkyne Cycloaddition for the Synthesis of 1,4‐Disubstituted Triazole (From 2018–2023). Chemistry & Biodiversity, 21.
DOI: 10.1002/cbdv.202400109.
Khoshnoud, A., & Pourali, A. (2021). Three-Component Synthesis of 1,4-Disubstituted 1,2,3-Triazoles using a Novel and Efficient Nano Alumina-Based Cu (II) Catalyst. Organic Preparations and Procedures International, 53, 509 - 517. DOI: 10.1080/00304948.2021.1971475.
Amosova, S., Martynov, A., & Potapov, V. (2022). 2-Bromomethyl-1,3-thiaselenole in Click Chemistry: Synthesis of 1-(2,3-Dihydro-1,4-thiaselenin-2-yl)-1H-1,2,3-triazoles via Copper-Catalyzed and Thermal 1,3-Dipolar Cycloaddition with Alkynes. Journal of Organometallic Chemistry. DOI: 10.1016/j.jorganchem.2022.122442.
Aflak, N., Ayouchia, H., Bahsis, L., Anane, H., Julve, M., & Stiriba, S. (2022). Recent Advances in Copper-Based Solid Heterogeneous Catalysts for Azide–Alkyne Cycloaddition Reactions. International Journal of Molecular Sciences, 23. DOI: 10.3390/ijms23042383.
Bonthula, S., Bonthula, S., Pothu, R., Srivastava, R., Boddula, R., Radwan, A., & Al-Qahtani, N. (2023). Recent Advances in Copper-Based Materials for Sustainable Environmental Applications. Sustainable Chemistry. DOI: 10.3390/suschem4030019.
Oubella, A., Bimoussa, A., Oussidi, A., Fawzi, M., Auhmani, A., Morjani, H., Riahi, A., Esseffar, M., Parish, C., & Itto, M. (2022). New 1,2,3-Triazoles from (R)-Carvone: Synthesis, DFT Mechanistic Study and In Vitro Cytotoxic Evaluation. Molecules, 27.
DOI: 10.3390/molecules27030769.
Wei, F., Wang, W., Y., Tung, C., & Xu, Z. (2016). Regioselective synthesis of multisubstituted 1,2,3-triazoles: moving beyond the copper-catalysed azide-alkyne cycloaddition. Chemical Communications, 52 (99), 14188-14199. DOI: 10.1039/c6cc06194j.
Sharma, R., & Kumar, A. (2022). An expeditious and clean synthesis of novel benzotriazole-triazole conjugates via copper-catalysed Azide-Alkyne cycloaddition click protocol (CuAAC)—Journal of Chemical Sciences, 134. DOI: 10.1007/s12039-022-02073-x
Peng, L., Zhao, Y., Okuda, Y., Le, L., Tang, Z., Yin, S., Qiu, R., & Orita, A. (2023). Process-Divergent Syntheses of 4- and 5-Sulfur-Functionalized 1,2,3-Triazoles via Copper-Catalyzed Azide-Alkyne Cycloadditions of 1-Phosphinyl-2-sulfanylethynes. The Journal of Organic Chemistry. DOI: 10.1021/acs.joc.2c02876.
Vilé, G., Di Liberto, G., Tosoni, S., Sivo, A., Ruta, V., Nachtegaal, M., Clark, A., Agnoli, S., Zou, Y., Savateev, A., Antonietti, M., & Pacchioni, G. (2022). Azide-Alkyne Click Chemistry over a Heterogeneous Copper-Based Single-Atom Catalyst. ACS Catalysis. DOI: 10.1021/acscatal.1c05610.
Roy, M., Sardar, B., Mallick, I., & Srimani, D. (2024). Generation of alkyl and acyl radicals by visible-light photoredox catalysis: direct activation of C–O bonds in organic transformations. Beilstein Journal of Organic Chemistry, 20, 1348 - 1375. DOI: 10.3762/bjoc.20.119
Ye, J., Ju, T., Huang, H., Liao, L., & Yu, D. (2021). Radical Carboxylative Cyclizations and Carboxylations with CO2. Accounts of Chemical Research. DOI: 10.1021/acs.accounts.1c00135.
Xiao, Q., Tong, Q., & Zhong, J. (2022). Recent Advances in Visible Light Photoredox Catalysis for the Thiol-Ene/Yne Reactions. Molecules, 27. DOI: 10.3390/molecules27030619
Wang, C., Li, Y., Cheng, X., Zhang, J., & Han, Y. (2016). Eosin Y dye-based porous organic polymers for highly efficient heterogeneous photocatalytic dehydrogenative coupling reaction. RSC Advances, 7, 408- 414. DOI: 10.1039/c6ra25123d.
Jarrahi, M., Maleki, B., & Tayebee, R. (2022). Magnetic nanoparticle-supported eosin Y salt [SB-DABCO@eosin] as an efficient heterogeneous photocatalyst for the multi-component synthesis of chromeno[4,3-b] chromene in the presence of visible light. RSC Advances, 12, 28886 - 28901. DOI: 10.1039/d2ra05122b.
Mohamadpour, F. (2022). New Role for Photoexcited Na2 Eosin Y via the Direct Hydrogen Atom Transfer Process in Photochemical Visible-Light-Induced Synthesis of 2-Amino-4H-Chromene Scaffolds Under Air Atmosphere. Frontiers in Chemistry, 10.
DOI: 10.3389/fchem.2022.880257.
Hu, X., Liu, Z., & Xiao, W. (2020). Radical Carbonylative Synthesis of Heterocycles by Visible Light Photoredox Catalysis. Catalysts.
DOI: 10.3390/catal10091054.
Kwon, K., Simons, R., Nandakumar, M., & Roizen, J. (2021). Strategies to Generate Nitrogen-centred Radicals That May Rely on Photoredox Catalysis: Development in Reaction Methodology and Applications in Organic Synthesis. Chemical Reviews.
DOI: 10.1021/acs.chemrev.1c00444.
Zhang, Z., & Gevorgyan, V. (2024). Visible Light-Induced Reactions of Diazo Compounds and Their Precursors. Chemical Reviews.
DOI: 10.1021/acs.chemrev.3c00869.
Varala, R., Dubasi, N., Kamsali, M., & Alam, M. (2025). Visible Light‐Driven Multicomponent Reactions for the Synthesis of Diverse Heterocyclic Frameworks. European Journal of Organic Chemistry. DOI: 10.1002/ejoc.202500216.
Xu, G., Xu, J., Feng, Z., Liang, H., Wang, Z., Qin, Y., & Xu, P. (2018). Dual C(sp3) -H Bond Functionalization of N-Heterocycles through Sequential Visible-Light Photocatalyzed Dehydrogenation/ [2+2] Cycloaddition Reactions. Angewandte Chemie, 57, 18, 5110–5114. DOI: 10.1002/anie.201710523.
Gisbertz, S., & Pieber, B. (2020). Heterogeneous Photocatalysis in Organic Synthesis. ChemPhotoChem. DOI: 10.1002/cptc.202000014.
Mohamadpour, F., & Amani, A. (2024). Photocatalytic systems: reactions, mechanism, and applications. RSC Advances, 14, 20609 - 20645. DOI: 10.1039/d4ra03259d.
Banerjee, S., Periyasamy, S., Muthukumaradoss, K., Deivasigamani, P., & Saravanan, V. (2025). Revolutionizing organic synthesis through green chemistry: metal-free, bio-based, and microwave-assisted methods. Frontiers in Chemistry, 13.
DOI: 10.3389/fchem.2025.1656935.
Pawlowski, R., Staněk, F., & Stodulski, M. (2019). Recent Advances on Metal-Free, Visible-Light- Induced Catalysis for Assembling Nitrogen- and Oxygen-Based Heterocyclic Scaffolds. Molecules, 24. DOI: 10.3390/molecules24081533.
Yadav, P., & Bhagat, P. (2024). Novel Metal‐Free Porphyrin with Ionic Liquid and Sulphonic Acid Moieties for Visible Light Assisted Photocatalytic C‐N Coupling of Heterocyclic Compounds with Aryl Halides. Asian Journal of Organic Chemistry.
DOI: 10.1002/ajoc.202400337.
Tabassum, S., & Govindaraju, S. (2022). White LED Light-Mediated Eosin Y-Photocatalyzed One-Pot Synthesis of Novel 1,2,4-Triazol-3-Amines by Sequential Addition. Topics in Catalysis, 68, 1523 - 1533. DOI: 10.1007/s11244-022-01590-w
Mishra, M., Srivastava, V., Singh, P., & Singh, P. (2022). Visible-light-driven Eosin Y-catalysed C(sp2)-H Functionalization/C-O Bond Formation for Synthesis of Benzoxazoles. Croatica Chemica Acta. DOI: 10.5562/cca3927.
Yan, J., Cheo, H., Teo, W., Shi, X., Wu, H., Idres, S., Deng, L., & Wu, J. (2020). A Radical Smiles Rearrangement Promoted by Neutral Eosin Y as a Direct Hydrogen Atom Transfer Photocatalyst. Journal of the American Chemical Society. DOI: 10.1021/jacs.0c02052.
Kumar, R., Garima, K., Srivastava, V., Singh, P., & Singh, P. (2024). Visible Light-Induced Eosin Y-Catalysed Green Synthesis of Substituted Pyrroles. Catalysis Letters, 155. DOI: 10.1007/s10562-024-04888-4.
Zhu, J., Cui, W., Wang, S., & Yao, Z. (2018). Radical Hydrosilylation of Alkynes Catalyzed by Eosin Y and Thiol under Visible Light Irradiation. Organic Letters, 20, 11, 3174-3178. DOI: 10.1021/acs.orglett.8b00909
Rana, B., Wagle, S., Singh, A., Sherpa, Y., Suwal, A., Khatri, S., & Subedi, G. (2023). Anti-Fungal Properties of Plant Extracts in vitro against Alternaria solani, the Cause of Early Blight in Potato. Journal of the Plant Protection Society. DOI: 10.3126/jpps.v8i1.56451.
Aravind, K., Prasad, M., Sagar, B., Naik, D., & Pushpavalli, S. (2024). Investigating the Antagonistic Effects of Novel Combination Fungicides against Fusarium oxysporum f. sp. ricini under in vitro conditions. Journal of Experimental Agriculture International.
DOI: 10.9734/jeai/2024/v46i113043.
Elsouk, A., Turky, Z., & Shahin, S. (2023). Screening of some wild plants as antifungal agents against phytopathogenic fungi. Journal of Environmental Studies and Researches. DOI: 10.21608/jesr.2023.287070.