One-pot multicomponent diastereoselective synthesis of indoline spirobicyclics using a recyclable chiral nanomagnetic
Danial Rafipour1, Ali Reza Sardarian2, Marzieh Jamali1
1Chemistry Department, College of Science, Shiraz University, Shiraz, 7194684795, Iran.
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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