Synthesis Of Ester Derivatives Of ¦Â-cyclodextrin

In this paper, the synthesis of such four β-cyclodextrin ester-derivatives as mono-6-O-tosyiβ-cyclodextrin;Heptakis(2,3-di-O-acetyl)-β-cyclodextrin;Heptakis(2,3 -di-O-hexanoyl)-β-cyclodextrin and β-cyclodextrin carbonate is studied and discussed. The productivity of mono-6-O-tosyl β-cyclodextrin is promoted from 7%, 11% reported in previous literature to about 18% through changing the adding mode of tosyl chloride. The effect of reaction conditions on the productivity is also concerned. Comparison of the synthesis of Heptakis(2,3-di-O-acetyl)-β-cyclodextrin and Heptakis(2,3-di-O-hexanoyl)-β-cyclodextrin reflects what the length of acyl affects the acylating step and deprotecting step. Two experimental schemes, the purpose of which is to grope the property of how dimethyl carbonate reacts with β-cyclodextrin are designed. The results show that dimethyl carbonate can not methylate the hydroxyl groups of β-cyclodextrin even with the presence of nucleophilic catalyst, but β-cyclodextrin carbonate is obtained and that dimethyl carbonate reacts regioselectively with the primary hydroxyl groups of β-cyclodextrin even under the condition the secondary hydroxyl groups tend to react preferentially. The structure of the synthesized β-cyclodextrin carbonate is deduced on the base of testing results and previous papers.