Novel cellulose supported 1,2-bis(4-aminophenylthio)ethane Ni(ii) complex (NiII(BAPTE)(NO3)2-Cell) as an efficient nanocatalyst for the synthesis of spirooxindole derivatives

Abstract

Cellulose was used as a support for immobilizing a Ni(II) complex of 1,2-bis(4-aminophenylthio)ethane to prepare Ni^II(BAPTE)(NO₃)₂-Cell as a new organo–inorganic hybrid nanocatalyst. The properties of the prepared catalyst were studied using various analyses such as FT-IR, XRD, SEM, TGA and EDX. Ni^II(BAPTE)(NO₃)₂-Cell was employed as a reusable catalyst for the synthesis of spirooxindole derivatives via a three-component condensation of isatin, malononitrile and reactive methylene compounds. The nanocatalyst can be readily and quickly separated from the reaction mixture and can be reused for at least eight successive reaction cycles without a significant reduction in efficiency. The facile accessibility to the starting materials, use of green solvents and conducting the reactions in eco-friendly and cost-effective conditions have made this protocol a suitable method for preparing spirooxindole derivatives.