Transesterification between dimethyl carbonate and phenol in the presence of (NH4)8Mo10O34 as a catalyst precursor Original Research Article

The novel catalyst system (NH4)8Mo10O34 was found to be active for transesterification between dimethyl carbonate and phenol based on the comparisons of performance over Sn-, Pb- and Mo-based metal complexes. X-ray diffraction (XRD), inductively coupled plasma–atomic emission spectroscopy (ICP–AES), the temperature-programmed desorption (TPD) with mass spectroscopy, thermogravimetic analysis (TGA), Infrared spectroscopy (FT-IR), and Raman spectroscopy were conducted to characterize the catalysts. (NH4)8Mo10O34 can be formed from (NH4)6Mo7O24·4H2O through calcinations at ∼423 K. The Mo species dissolved from (NH4)8Mo10O34 appeared to play the main part in this reaction. This homogeneous catalyst showed the superior turnover frequency to those of the homogeneous lead complexes obtained from PbO. The activation energy was determined to be 87.1 kJ mol−1.