Synthesis and Characterization of the β-cyclodextrinmonomers with Vinyl Functional Groups

In this paper, three kinds of β-cyclodextrin monomers with vinyl functional groups were synthesized by amidation reaction and necleophilic reaction to improve the preparation efficiency and enrich the monomers.The definite means were as follows:Firstly, the active aminogroups was introduced by the reaction of single-6-p-methylbenzene sulfonyl-β-cyclodextrin (β-CD-6-OTs) and ethylenediamine (EDA).Secondly, the target compounds were synthesized via amidation reaction using 1-(3-dimethylaminopropyl) -3-ethylenediamine hydrochloride (EDCI)/1-hydroxybenzotriazole (HOBT) as their activating agent and N, N-diisopropylamine (DIPEA) as their acid-binding agent.Using NaH as the catalyst and 3-allyl bromideas the chemistry modifier, the β-cyclodextrinderivative (Allyl-β-CD) was synthesized. The structure of compounds was further confirmed by mass spectrum, fourier transform infrared spectrometer, and 1 H-nuclear magnetic resonance spectra.The results showed that amination and nucleophilic reactions were carried out in accordance with the input ratios of β-CD-6-E (1.0 eq), AAc/SA-AC (1.2 eq), HOBT (1.2 eq), DIPEA (3.3 eq), EDCI (1.5 eq) and β-CD (1.0 eq), NaH (20 eq), and 3-bromopropylene (2.9), respectively, under the room temperature conditions.Characterization results showed that the double bond was bonded to the β-cyclodextrin, obtaining single-6-acryloyl ethylenediamine-β-cyclodextrin (β-CD-6-EA), single-6-acryloyl syringic acid-β-cyclodextrin (β-CD-6-SA-AC) and disubstituted 6-o-allyl-β-Cyclodextrin (Allyl-β-CD). Then, the improved method was used to prepare β-cyclodextrin monomers with vinyl functional groups, which was not only easy to operate and efficient, but also increased the variety and quantity of polymerizable cyclodextrin monomers, which would provide the application basis and ideas for the preparation of various functional cyclodextrin polymers in the future.