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. 2025 Jul 22;15(1):26584.
doi: 10.1038/s41598-025-08820-7.

Amino acid-based deep eutectic solvent as a versatile catalyst for the green synthesis of chromenopyrimidines

Afagh Ranjbaran  1 , Davood Habibi  2 , Arezo Monem  1 , Nastaran Dehnokhalaji  1
Affiliations

Amino acid-based deep eutectic solvent as a versatile catalyst for the green synthesis of chromenopyrimidines

Afagh Ranjbaran et al. Sci Rep. .

Abstract

A novel deep eutectic solvent (Thr/Mal-DES) was synthesized by mixing one mole of L-threonine (Thr) with one mole of malonic acid (Mal) and was characterized by FT-IR, 1H NMR, TGA/DTA, and densitometry techniques. Then, it was used as a highly effective catalyst for the rapid synthesis of chromeno[4,3-d]pyrimidines from the reaction of 4-hydroxy-coumarin, urea/thiourea and aldehyde under solvent-free conditions at 80 °C in high yields and short reaction times.

Keywords: Catalysis; Chromenopyrimidines; Deep eutectic solvent; L-threonine; Malonic acid.

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Conflict of interest statement

Declarations. Competing interests: The authors declare no competing interests.

Figures

Fig. 1
Fig. 1
Preparation of Thr/Mal-DES.
Fig. 2
Fig. 2
Synthesis of 2(a-m) by Thr/Mal-DES.
Fig. 3
Fig. 3
The eutectic points phase diagram.
Fig. 4
Fig. 4
The FT-IR spectra of (a), (b), (c), and (d).
Fig. 5
Fig. 5
The 1H NMR of Thr/Mal-DES.
Fig. 6
Fig. 6
The TGA-DTA pattern of Thr/Mal-DES.
Fig. 7
Fig. 7
Synthesis of diverse 2(a-m).
Fig. 8
Fig. 8
Proposed mechanism for the synthesis of 2(a-m).
Fig. 9
Fig. 9
Reusability of Thr/Mal-DES catalyst in four consecutive reaction runs.
See this image and copyright information in PMC

References

    1. Hayyan, M. et al. Saheed, O. K. Are deep eutectic solvents benign or toxic. Chemosphere90, 2193–2195 (2013). - PubMed
    1. Dai, Y., Van Spronsen, J., Witkamp, G. J., Verpoorte, R. & Choi, Y. H. Ionic liquids and deep eutectic solvents in natural products research: Mixtures of solids as extraction solvents. J. Nat. Prod.76, 2162–2173 (2013). - PubMed
    1. de Domínguez, P. Recent trends in (ligno) cellulose dissolution using neoteric solvents: Switchable, distillable and bio-based ionic liquids. J. Chem. Technol. Biotechnol.89, 11–18 (2014).
    1. Buzatu, A. R., Todea, A., Peter, F. & Boeriu, C. G. The role of reactive natural deep eutectic solvents in sustainable biocatalysis. ChemCatChem13, e202301597 (2024).
    1. Santana-Mayor, Á., Rodríguez-Ramos, R., Herrera-Herrera, A. V., Socas-Rodríguez, B. & Rodríguez-Delgado, M. Á. Deep eutectic solvents. The new generation of green solvents in analytical chemistry. TrAC Trends Anal. Chem.134, 116108 (2021).

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