Surface Properties and the Catalytic Activity of Amorphous Iron Aluminophosphates: Effect of Fe Loading

Abstract

ABSTRACT. Iron aluminophosphates (FeAlP) with different percentage of iron were synthesized and characterized for their surface and bulk properties. The catalytic activity was determined in the transesterification of diethyl malonate with benzyl alcohol. Benzyl ethylmalonate and dibenzyl malonate were obtained as the only products. FeAlP with 0.025 mole % of iron was found to be distinctly different in its textural and catalytic properties. Formation of diester was found to be favored by the acid sites of intermediate strength.The presence of hydrated alumina and the polycondensed phosphates in the materials reduced the catalytic activity of iron aluminophosphates in transesterification reaction.

Amorphous Mesoporous Iron Aluminophosphate Catalyst for the Synthesis of 1,5-Benzodiazepines

“…The better catalytic activity of FeAlP-550 over that of the other catalysts reported may be attributed to its mesoporous texture and amorphous nature, which gave a higher concentration of active acid sites on its surface [30]. We have previously reported a correlation between the textural/structural properties and catalytic activity of these materials in organic transformations like tranesterification and alkylation reactions [28,29].…”

“…The iron aluminophosphate (FeAlP) catalyst was prepared by co-precipitation [27][28][29][30]. Aluminum nitrate (Al(NO 3 ) 3 •9H 2 O), ferric nitrate (Fe(NO 3 ) 3 •9H 2 O), and 85% H 3 PO 4 in a definite molar ratio (Al:Fe:P = 0.95:0.025:1) were dissolved in 500 ml of deionized water and stirred vigorously.…”

“…The application of aluminophosphates as heterogeneous catalytic materials in organic synthesis is growing significantly. Our group has recently reported the catalytic activity of amorphous metal aluminophosphates as effective and recyclable materials in organic transformations [27][28][29][30]. To synthesize diazepines by an effective and environmentally benign route, we have condensed OPDA with various ketones in the presence of metal aluminophosphates as catalyst.…”