Page 26 - חוברת תזות הנדסה ירוקה 2024

polysaccharide, while the system was tested for metathesis reactions with different reagents: diethyl diallylmalonate )DEDAM(, allylbenzene, and N,N-diallyltosylamide, in polar and non-polar solvents )ethanol, ethyl acetate, hexane, and toluene( at 40°C, and 60°C, and different catalyst to substrate molar ratio of 1% and 3%. The DEDAM reagent yielded the best results, and high conversions were obtained after 24 hours in both the homogeneous and heterogeneous reactions without leaching the complex from the heterogeneous system: 100% in homogeneous reactions in all solvents, and 92% in ethanol, 98% in ethyl acetate, 93% in hexane and 100% in toluene, with the heterogeneous system at 60°C, with cat/sub=3%. Six cycles were obtained in non-polar solvents, in contrast to the greatly decreased conversions seen during the second cycle in polar solvents. The characterization of the complex in the polysaccharides was done with FTIR, TGA, SEM, and EDS analyses. The FTIR chromatograms indicated that the ruthenium complex was attached to the polysaccharide through the negatively charged sulfate ester and hydroxyl groups; the SEM and TGA analyses of λ-FixCat showed a more ordered structure and higher thermal compared to the xerogel of native λ.
Keywords: ligands FixCat, PhenS, TXPTS, metathesis reaction, polysaccharides, Suzuki reaction.
Book Of Abstracts | Class 2023
26