Vanadium-apatite containing the VO(4)(3-) species was synthesized. Several characterization techniques such as XRD, TEM, XPS, ESR, UV-vis DRS, V K-edge XAFS, (51)V MAS NMR, Raman spectroscopy, and CO(2) TPD revealed that the vanadium-apatite was Ca(9)(VO(4))(5)(HVO(4))(OH), abbreviated to VAP, covered with calcium oxide. This surface-coated calcium oxide phase could be removed by washing with water and then, the monomeric V-OH species having the strong Bronsted basicity were generated on the surface of VAP. The strong basicity of the solid VAP-catalyzed efficient Michael reaction in water solvent. Furthermore, VAP was found to be applicable to the direct synthesis of pyrazolinone derivatives using aryl hydrazines and diethyl ethoxymethylenemalonate. (C) 2009 Elsevier B.V. All rights reserved.