An efficient Knoevenagel condensation of aldehydes with active methylene compounds over novel, robust CeZrO4−δ catalyst.

Abstract: In the present work, we explored novel CeZrO_4−δ as a catalyst for Knoevenagel condensation of aldehydes with reactive methylene compounds like malononitrile and ethylcyanoacetate. For the present study, ceria, zirconia and CeZrO_4−δ were prepared by gel combustion method and well characterized using XRD, SEM, EDX, BET and TPD analyses, etc. A wide range of aldehydes were effectively condensed over novel CeZrO_4−δ with reactive methylene compounds with high yields. In addition, the CeZrO_4−δ was effectively reused for five consecutive cycles without significant loss in its activity. To the best of our knowledge, this is the first liquid-phase application of pure CeZrO_4−δ.Graphical abstract: [ABSTRACT FROM AUTHOR]