Derivatization of valproic acid using ferrocene derivatives: Synthesis, characterization and investigation of optical and electrochemical properties

New ferrocenyl‐based valproic acid (VPA) ester derivatives were designed and synthesized according to the reaction of appropriate haloalkylferrocene derivatives with VPA in the presence of K 2 CO 3 and a catalytic amount of 18‐crown‐6 ether. Elemental analyses and Fourier transform infrared, 1 H NMR, 13 C NMR and mass spectra all well confirmed the predicted molecular structure. This is the first report in which ferrocene has been applied in derivatization of VPA as a chromogenic group. The electrochemical properties of the synthesized compounds were studied using cyclic voltammetry measurements, and energies of the frontier molecular orbitals were determined. In addition, the solubilities of the final compounds were studied in distilled water, phosphate buffer (pH = 7.4) and 0.9% (w/v) NaCl solution.