Influence of Nitrogen-content of a New Aluminophosphate Oxynitride Catalyst - Alpon in Knoevenagel Condensation

A new high surface area solid basic catalyst with tunable acid-base properties has recently been proposed [R. Marchand, R. Conanec, Y. Laurent, Ph. Bastians, P. Grange, L.M. Gandia, M. Montes, J. Fernandes and I. Odriozola, patent application FR 940108 1; R. Conanec, R. Marchand, Y. Laurent, Ph. Bastians and P. Grange, in Soft Chemistry Routes to New Materials, Nantes, France, in press; P. Grange, Ph. Bastians, R. Conanec, R. Marchand and Y. Laurent, Chem. Commun., submitted for publication). Starting from aluminophosphate (AlPO4) oxide precursor and with careful adjustment of the nitridation procedure, it is possible to modify the global composition, changing the O/N content of the nitrided aluminophosphate (AlPON). This letter evidences that conversion in the malononitrile-benzaldehyde condensation largely depends on the O/N ratio of these new catalysts. Such basic solids are compared with conventional MgO catalyst.