Wadsworth–Emmons Reaction by Using the Fluorapatite Catalyst: Kinetic Studies

Abstract

Wadsworth−Emmons reaction was successfully carried out by using the fluorapatite (FAP) catalyst. The reaction of 2methoxybenzaldehyde and triethylphosphonoacetate using FAP afforded α,β-unsaturated ester with 100% conversion and 80% selectivity. A kinetic model was validated at different temperatures by Langmuir− Hinshelwood−Hougen−Watson (LHHW), and the absence of mass transfer resistance was verified by the Weisz Prater criterion. The effect of different catalysts, temperature, catalyst loading, solvent, mole ratio, and speed of stirring was studied. The FAP catalyst was characterized by Fourier transform infrared spectroscopy, Brunauer−Emmett−Teller method, nitrogen adsorption−desorption, transmission electron microscopy, energy-dispersive X-ray spectroscopy, temperature programmed desorption (TPD-NH 3 ), X-ray diffraction, and X-ray photoelectron spectroscopy. The FAP catalyst was found to be stable up to three recycles with no loss in activity.

Copper Fluorapatite-Catalyzed Aza-Michael Reaction and Kinetic Studies

“…The acid strength was obtained from the area under the peaks from weak to very strong temperature from Figure and mentioned in terms of peak area % in Table . The acid strength distribution is shown in Figure .…”