SYNTHESIS OF BIS-SPIRO-SUBSTITUTED PIPERIDINES USING Fe3O4@SiO2-SO3H NANOCATALYST UNDER ULTRASONIC CONDITIONS

SYNTHESIS OF BIS-SPIRO-SUBSTITUTED PIPERIDINES USING Fe3O4@SiO2-SO3H NANOCATALYST UNDER ULTRASONIC CONDITIONS

An efficient pseudo six-component synthesis of 15-(aryl)-3,3,11,11-tetramethyl-15- azadispiro[5.1.5.3]hexadecane-1,5,9,13-tetrone is described by one-pot condensation of formaldehyde, dimedone, and aromatic amine using Fe3O4@SiO2-SO3H nanocatalyst under ultrasonic conditions. The catalyst was characterized by powder X-ray diffraction (XRD), scanning electronic microscopy (SEM), energy dispersive X-ray (EDS), and FT-IR spectroscopy. Use of simple and readily available starting materials, experimental simplicity, applying the sonochemical methodology as an efficient method and innocuous means of activation in synthetic chemistry are some advantages of this protocol.