Potassium fluoride doped fluorapatite and hydroxyapatite as new catalysts in organic synthesis

Fluorapatite (FAP) and hydroxyapatite (HAP) were prepared and doped with potassium fluoride. KF/FAP and KF/HAP were prepared by usual impregnating method. The doped materials were characterised by X-ray diffraction, BET surface area, BJH total pore volume and scanning electron microscopy (SEM). All this data were compared to that of unimpregnated apatites. Some modifications in the particles morphology were observed by doping apatites with KF The comparison of the catalytic activity of KF, FAP, HAP, KF/FAP and KF/HAP indicate clearly the positive effect of the doping apatites by KF in the Knoevenagel condensation used as model reaction. In this work, KF/FAP and KF/HAP were prepared and used for the first time as new and efficient catalysts in heterogeneous solid-liquid synthesis. (C) 2003 Elsevier Science B.V. All rights reserved.