Preparation of Mg/Al layered double hydroxide (LDH) with structurally embedded molybdate ions and application as a catalyst for the synthesis of 2-adamantylidene(phenyl)amine Schiff base

Abstract

Preparation of MoO42−-containing Mg/Al layered double hydroxide (LDH) using co-precipitation method has been suggested. The possibility of introduction of molybdate ions from solutions with different concentrations of molybdate to the structure of LDH has been investigated. For this purpose, the mixture of magnesium and aluminium nitrates was added to the solution of molybdate or vice versa. The XRD patterns of obtained specimens showed formation of layered double hydroxide phases without any impurities. The basal spacing of formed LDH was not affected when concentration of molybdate used in the synthesis process was low. However, at higher concentration of molybdate an increase of cell parameter c was observed. The determined Mg/Al ratio and the amount of Mo in LDH were found to be dependent on the preparation conditions. Molybdate-containing LDH was tested as a catalyst in solvent free synthesis of 2-adamantylidene(phenyl)amine. It was demonstrated, that the addition of molybdenum in LDH improved the yield of Schiff base.