Optically Active Liquid Crystalline Polyoxometalates via Electrostatic Encapsulation with Cholesterol-Containing Amphiphile

• Published in: Chemistry, an Asian journal Vol. 11; no. 14; pp. 2001 - 2005
• Main Authors: Zhang, Jing, Li, Jingfang, Yuan, Hong, Zhang, Guohua, Li, Bao, Li, Wen, Wei, Xuehong, Duan, Xin-E, Wu, Lixin
• Format: Journal Article
• Language: English
• Published: Germany Blackwell Publishing Ltd 20.07.2016; Wiley Subscription Services, Inc
• Subjects: amphiphiles; Chemistry; Ions; liquid crystals; optical activity; polyoxometalates; supramolecular self-assembly; amphiphiles; liquid crystals; supramolecular self-assembly; optical activity; polyoxometalates
• ISSN: 1861-4728; 1861-471X
• DOI: 10.1002/asia.201600532

A novel cholesterol‐containing amphiphile was designed and prepared in the study, which is a room‐temperature ionic liquid crystal over a broad temperature range with pronounced chiroptical properties. Four types of inorganic polyoxometalates (PMs) with different numbers of charges were encapsulated by the chiral amphiphile. The incorporation of chiral organic cations triggers achiral PMs in the complexes to show induced chirality through intermolecular interactions, as demonstrated by circular dichroism spectroscopy. The electrostatic encapsulation with mesomorphic promoters provides the inorganic PMs with liquid crystalline behavior, characterized by differential scanning calorimetry, polarized optical microscopy, and X‐ray diffraction. The strategy applied herein represents a unique example of liquid crystalline PM complexes with optical activity. A good promoter: A chiral amphiphile, which is a room‐temperature ionic LC over a broad temperature range, was designed and prepared as a chiral promoter. The incorporation of the chiral amphiphile triggers achiral polyoxometalates in the complexes to show induced CD signals through intermolecular interactions. The electrostatic encapsulation with the promoter provides the inorganic PMs with LC behavior.