Design and Synthesis of Zirconium-Containing Coordination Polymer Based on Unsymmetric Indolyl Dicarboxylic Acid and Catalytic Application on Borrowing Hydrogen Reaction

Catalytic borrowing hydrogen reaction is a very attractive transformation in the field of C-alkylation reaction. In this work, a new Zr (Zirconium)-containing coordination polymer containing unsymmetric indolyl dicarboxylic acid 1-(carboxymethyl)-1H-indole-5-carboxylic acid (H(2)CIA) was synthesized by the way of a solvothermal synthetic route and characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Nitrogen adsorption-desorption, fourier transform infrared spectroscopy and X-ray photoelectronic spectroscopy (XPS). The coordination polymer Zr-CIA was employed as the catalyst for C-alkylation of acetophenone derivatives in the presence of benzyl alcohol. In addition, Zr-CIA catalyst was also observed to be effective in the reaction of alcohols with alcohols and high yields of alkylation products were achieved. Mechanism investigations were also conducted to better understand the catalysts and transformations. Meanwhile, the Zr-CIA could be reused at least five times without a notable decrease in activity and selectivity.