Study On The Synthesis Of Pentaerythritol Derivatives Catalyzed By Solid Superacid

Solid superacid catalyst received wide attention due to its strong acidity, highcatalytic activity, recycling, no corrosion to equipment, the environmental advantagesof no pollution and simple post-processing, and being a kind of catalyst with goodindustrial application prospect. Solvent-free synthesis has been applied in a variety oforganic synthesis reaction because of its simple operation, low energy consumption,high selectivity, high reaction efficiency. In this thesis, the advantages of both werecombined, and a series of reactions of pentaerythritol have been studied undersolvent-free conditions by using modified SO42-/MxOytype solid superacid ascatalyst.Under solvent-free conditions, using the self-made SO42-/TiO2-SnO2solidsuperacid as catalyst, the esterification reaction of pentaerythritol with carboxylic acidwas studied, and pentaerythritol stearate, pentaerythritol oleate, and chloroaceticpentaerythritol tetraester were synthesized. The catalyst dosage, mole ratio of rawmaterials, and reaction conditions such as temperature and time are optimized, and thegood experimental results were obtained. The highest yields of pentaerythritol stearate,pentaerythritol oleate and chloroacetic pentaerythritol tetraester is up to89.4,91.5,and98.7%, respectively. The mechanism of solid superacid catalyzed esterificationreaction of pentaerythritol is suggested and discussed.Under solvent-free conditions, the condensation reaction of pentaerythritol withaldehyde or ketone was studied by using the improved SO42-/TiO2-ZrO2solidsuperacid as catalyst. Acetophenone pentaerythritol ketal, propiophenonepentaerythritol ketal, p-fluorobenzaldehyde pentaerythritol acetal and2,4-dichloro-5-fluoroacetophenone pentaerythritol acetal were synthesized, and thereaction conditions including reaction temperature, mole ratio of reactants, catalystdosage and reaction time were optimize, and the higher yields of products wereobtained. The mechanism of condensation reaction catalyzed by the catalyst isdiscussed.SO42-/MxOytype solid superacid displayed high catalystic activity in thereactions above mentioned. The synthetic compounds are characterized by IR,1HNMR, and MS. The crystal structures of some compounds were determined by X-raysingle crystal diffraction. The best reaction conditions were obtained, and this workprovides a solid foundation for the industrial application and cleaner production of pentaerythritol derivatives.