Abstract
Fe₃O₄@SiO₂-NH-TCT–(trans-4-hydroxy-L-proline)₂ nanoparticles were synthesized as a chiral, magnetically recoverable nanocatalyst. The material was thoroughly characterized by FT-IR, VSM, XRD, TEM, FE-SEM, BET, CHNS elemental analysis, mass spectrometry, and ¹H/¹³C-NMR. The catalyst enabled a one-pot, multicomponent diastereoselective synthesis of indoline spirobicyclic derivatives from anilines, carbon acids, Fischer’s base, and aldehydes under solvent-free conditions at ambient temperature. The method afforded high to excellent yields with excellent diastereoselectivity. Product structures and anti/syn diastereomeric ratios were established by ¹H-, ¹³C-NMR, 2D-ROESY, mass spectrometry, and single-crystal X-ray diffraction.
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The authors gratefully acknowledge the University of Shiraz for its support through the provision of facilities.
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Danial Rafipour : Data curation, formal analysis, investigation, resources, validation, visualization, writing original draft; Marzieh Jamali: Formal analysis, investigation, methodology, writing original draft, project administration; Ali Reza Sardarian : conceptualization, supervision, writing-review&editing, funding acquisition; Saeed Davoodi: Formal analysis, validation, investigation.
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Rafipour, D., Sardarian, A.R., Jamali, M. et al. One-pot multicomponent diastereoselective synthesis of indoline spirobicyclics using a recyclable chiral nanomagnetic L-proline catalyst under mild conditions. Sci Rep (2026). https://doi.org/10.1038/s41598-026-40598-0
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DOI: https://doi.org/10.1038/s41598-026-40598-0
