title: Engineering Thiol-Ene Click Chemistry for the Fabrication of Novel Structurally Well-Defined Multifunctional Cyclodextrin Separation Materials for Enhanced Enantioseparation.
abstract: The preparation of two novel multifunctional cyclodextrin (CD) separation materials and their ultimate enantioseparation performances in high performance liquid chromatography are reported. A mild thiol-ene click reaction was used to anchor 1-allylimidazolium-per(p-methyl)phenylcarbamoylated-β-CD and 1-allylimidazolium-per(p-chloride)phenylcarbamoylated-β-CD onto thiol-modified porous silica giving structurally well-defined stable cationic multifunctional CD chiral stationary phases (CSP1 and CSP2 respectively). These covalently bonded CD phases have typical interaction modes such as H-bonding, π-π effect, electrostatic and dipole-dipole interactions as well as steric effects which result in superior chiral resolution for a variety of chiral compounds in different separation modes. In a reverse-phase mode, both CSPs exhibited excellent separation abilities for isoxazolines, flavonoids, β-blockers, and some other neutral and basic racemates. In a polar-organic mode, isoxazolines and flavonoids were well resolved. CSP1 with an electron-rich phenyl substitution on the CD rims gave a better resolution for isoxazolines whereas CSP2 with an electron-deficient phenyl substitution on the CD rims gave better resolution for flavonoids. Among isoxazolines, 4ClPh-OPr gained a high selectivity and resolution up to 18.6 and 38.7, respectively, which is an amazing result for CD enantioseparation materials.
authors.affiliation: Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, China.
authors.forename: Xiaobin
authors.initials: X
authors.lastname: Yao
authors.forename: Hao
authors.initials: H
authors.lastname: Zheng
authors.affiliation: Weifang Teda Environmental Protection Equipment Co., Ltd., Weifang 262100, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, China.
authors.forename: Xiaofei
authors.initials: X
authors.lastname: Ma
authors.affiliation: Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, China.
authors.forename: Yin
authors.initials: Y
authors.lastname: Xiao
authors.affiliation: Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Wang