The Synthesis Of CO₂-Philic Carbonhydrate Compounds And The Simulation And Calculation Of Their Interaction With CO₂

As an environmentally benign solvent, carbon dioxide (CO2) has held considerable researchers’attention for decades. In order to develop more application areas of CO2 and increase its capability of dissolve polar solutes, it is necessary to design and synthesis CO2-philes. Carbohydrate is one of the most attractive hydrocarbons owing to its bio-degradability and abundant with hydroxyl groups. Acetated sugars present excellent solubility in liquid besides scCO2. Thus, D-glucopyranose is selected to design and synthesis CO2-philes which have functional groups and different structures. And the reaction conditions were optimized.(1) The optimal synthesis conditions of per-O-acetylated a-D-glycopyranose was optimized as 1 g D-glycopyranose in 4mL acetic anhydride and 10mL pyridine at-20℃ for 23 h, and the yield was 83.0%.(2) The optimal synthesis conditions of per-O-acetylated P-D-glycopyranose was optimized as 4 g D-glycopyranose and 4 g Sodium acetate in 22mL acetic anhydride at 80℃ for 2 h, and the yield was 79.32%.(3) The optimal hydrolysis conditions of per-O-acetylated a-D-glycopyranose employed 2.56 mmol per-O-acetylated a-D-glycopyranose and 3.0 equiv. of ammonium carbonate in 2 mL DMF at 25℃, and the yield was 92.13%.(4) The ten kinds of saccharide derivatives were prepared by the a or β-D-Methylglucoside and acetic anhydride, propionic anhydride, butyryl chloride, isobutyryl chloride, benzoyl chloride.(5) The structure of carbohydrate compounds were characterized by the melting point, specific rotation,1H-NMR, IR and other means.The quantum chemical calculations were performed on the research of the interaction between CO2-philes and CO2. The effects of different groups, the length of carbon chain and the number of terminal methyl on the interaction were discussed:(1) The average ΔE values of per-O-acetylated a-D-glycopyranose-CO2 is higher than that of per-O-acetylated β-D-glycopyranose-CO2.(2) The average AE values of three sugar acetates is 2,3,4,6-tetra-O-acetyl-D-glucopyranoside< per acetylated D-glycopyranose< Methyl 2,3,4,6-tetra-O-acetyl-D-glucopyranoside.(3) By comparison the average AE values of acetylated, propionylated and butyrylated D-Methylglucoside, it is found that the average AE values rise with the growth of the carbon chain except the acetylated a-D-Methylglucoside.(4) By comparison the average AE values of isobutyrylated, propionylated and butyrylated D-Methylglucoside, it is found that the steric hindrance increases with more terminal methyl and the average ΔE values will be down.