Novel bio-based core-shell organic-inorganic nanohybrid from embedding aspartic acid-guanine ionic liquid on the hydroxylated nano silica surface (nano [(Asp-Gua) IL@PEG-SiO2]): A versatile nanostructure for the synthesis of bis(2,3-dihydroquinazolin-4(1H)-one) derivatives and tricarboxamides under green media

A new multi-layered nano structure has been prepared using hydroxylated nano silica (as core) and novel guaninium aspartate ionic liquid (as shell) (nano [(Asp-Gua) IL@PEG-SiO2]). It characterized by FT-IR, H-1 NMR, FESEM, EDAX, XRD, TGA/ DTG, and BET analysis. This bio-based organic-inorganic hybrid catalyzed synthesis of peptide-like tricarboxamides though the pseudo five-component condensation of aromatic aldehydes, aromatic amines, tert-butyl isocyanide, and Meldrum's acid under green solventless conditions at room temperature successfully. Its efficacy affirmed in the preparation of bis (2,3-dihydroquinazolin-4(1H)-one) derivatives via one-pot pseudo five-component reaction of aldehydes, amines, and isatoic anhydride in 70 degrees C aqueous media. The protocol contains several advantages such as relatively short reaction times, simple work-up procedure, economic and environmentally-friend because of performing the two class of MCRs under green media, utilizing wide-range of substrates, and reusability and recoverability of the core-shell nano-promoter for 3 runs without significant activity loss. (C) 2020 Published by Elsevier Ltd.