D-phenyl alanine-oxalic acid (D-Phe-Ox): A novel nano ionic liquid catalyzing the one-step green synthesis of functionalized spirolactones and dispirodihydro-furanyl oxindoles

In this paper, a new nano-size ionic liquid (nIL) has been synthesized from D-phenylalanine and oxalic acid (D-Phe-OX) via a simple procedure. The obtained nIL has been characterized by the fourier transform infrared spectroscopy (FT-IR), energy-dispersive X-ray spectroscopy (EDAX), thermogravimetric analysis (TGA), nuclear magnetic resonance spectroscopy (1H NMR), and field emission scanning electron microscopy (FESEM), techniques. The synthesized nanocatalyst has been used for the three-component one-step synthesis of functionalized spirolactones via the condensation reaction of arylamines, DMAD and isatins. The stereoselective preparation of dispirodihydrofuranyl oxindoles has also been examined successfully through the one-step pseudo-four component condensation of isatins, amines and DMAD, respectively.