Twenty-five inorganic solids studied as supports for KF were screened with respect to the synthesis of the azalactone obtained by dry-media condensation of p-hydroxybenzaldehyde with hippuric acid in acetic anhydride (1 ∶ 1 ∶ 4, molar ratio), in 3 g of 10 wt% KF support catalysts. The results obtained indicate that there was a number of supported KF catalysts with conversions higher than or comparable to that obtained by the classical Erlenmeyer method of azalactone synthesis. Furthermore, not only were there very important differences in the catalytic behavior of different KF support systems, but also these differences are closely related to the procedure used in the reaction heating. In this respect, the well-documented KF–Al₂O₃ was the best catalyst when reactions were conducted under conventional heating. However, when reactions were carried out in a domestic microwave oven, KF supported on AlPO₄, TiO₂ or Zn₃(PO₄)₂ were better catalysts than KF–Al₂O₃. The importance of the textural and acid–base properties of solid inorganic supports was also demonstrated with respect to the catalytic behavior of supported KF catalysts. Finally, results obtained in the synthesis of thirteen different azalactones, lead us strongly to recommend the procedure using microwave irradiation and KF–AlPO₄, over classical heating with KF–Al₂O₃. The advantages are good yields, easier work-up, a significant decrease in reaction times, and easy re-use of catalysts when operated in dry-media, especially by use of a domestic microwave oven.