Synthesis of Unsymmetrical Ethers Catalysed by Polyvinyl Sulfuric Acid & PVSA / Nano RH SiO2 as a Novel Solid Acid Nanocomposite

The methodology involves preparing polyvinyl sulfuric acid as a solid acid by simple mixing of polyvinyl alcohol with chlorosulfonic acid in CH2Cl2 at room temperature. The catalytic ability of the solid acid was investigated for the facile conversion of benzylic alcohols to the unsymmetrical ethers with aliphatic alcohols in the presence of the solid acid. Results show that the solid acid is an appropriate catalytic agent for these condensation reactions. The silica was also extracted from low-cost rice husk and the amorphous silica gel nanoparticles were prepared with sol- gel method. The polyvinyl sulfuric acid was supported on nano rice husk silica. Then the catalytic effect of this system was investigated for synthesis of unsymmetrical ethers which consisted of a combination of high acidic power for this solid acid and high- surface area of nanoparticles. Results show that totally catalytic effect of polyvinyl sulfuric acid supported on nano silica is more suitable than polyvinyl sulfuric acid. The reason for this is in its ability to produce the end products in shorter reaction times while having high isolated yields.