New Synthesis Processes Of Sulfopropyl Ether β-cyclodextrin Derivatives

Sulfopropyl etherβ-cyclodextrin（SPE-β-CD）with highly anionic characteristic played various roles including chiral selectors,inclusion compounds,precursors,dopants and etc.in chemical synthesis.In this thesis,the SPE-β-CDs were synthesized using three new processes motivated by microwave irradiation（MW）and catalyzed by electrolyzed alkaline water,which were actually very efficient and eco-friendly with low energy consumption and high-quality products,and could be applied in other derivatives synthesis like hydroxy-,carboxyalkyl-.Three-step method,MW assisted method and electrolyzed alkaline water method were proposed at first to synthesize SPE-β-CDs respectively.The solution was filtered with the glucan gel filtration to wash out the inorganic salts,and then evaporated the water to get white crystal products.Then products structures were characterized by FT-IR,DSC,and ¹³C NMR spectroscopy.Average degree of substitution（DS）were calculated by ¹H NMR spectroscopy,MS and element analysis.Finally,the influence of four reaction parameters（e.g.the molar ratio,alkaline concentration,reaction temperature,reaction time）on DS of SPE-β-CD was investigated thoroughly.Afterwards,parameters were optimized.The experimental results showed that:（1）Products with specific DS including 2,4,5,6,and 7 were successfully synthesized in this paper.The mass spectrum indicated that the obtained product was a mixture of SPE-β-CD with different DS;the average DS calculated by the elemental analysis method was more in line with the actual value;according to the ¹H/¹³C NMR spectrum,it could be found that under pH control,substitution took place preferentially at the C₆ position;DSC results showed that the thermal stability of the substituted product was lower than that ofβ-CD.（2）The high efficiency of the microwave action made not only the reaction time and the amount of alkaline solvent were reduced significantly,but also the yield increased up to 80%.With the temperature and energy distribution became more uniform under the new method accordingly,the normal distribution trend of the product became more obvious,and the DS in each interval also had a different proportion of improvement.The aforementioned results could be better reproduced through the novel synthesis process.（3）Two effective developed solutions were chosen out through thin layer chromatography.They were Water/ethanol/concentrated ammonia=3:6:0.8（v/v）,water/ethanol/ether/concentrated aqueous ammonia=3:6:1:1（v/v）,which provided a simple and feasible mean for real-time monitoring of reaction and purification of the single-substitution and double-substitution products.