Inositol Liquid Crystals, X-Ray Diffraction Studies of Their Hydrogen-Bond Supported Supramolecular Mesophases¹

Abstract

Results of x-ray measurements on the various columnar mesophases of multi-ethers of the naturally occurring stereoisomers myo- and scyllo-inositol are presented. Depending on the number of alkyl substituents at their inositol cores such derivatives show interesting kinds of molecular organization in their liquid-crystalline states. Thus, to the best of our knowledge, the first thermotropic mesophase of tetragonal symmetry exhibited by a low-molecular weight system is described. Vicinal diols and a tetrol of this new group of liquid crystals are coupled within their mesophases by hydrogen bonding networks. In case of scyllo-inositol it could be shown that the number of functionalizations determines the size of this network or the degree of multimerization; columnar mesophases composed of dimers or pentamers were observed. A comparison of stereoisomeric inositol tetraethers (vicinal cis- and trans-diols) clearly revealed stereochemical influences on their liquid-crystalline properties.

Key Words:

• inositols natural product
• derivatives
• 2H-NMR
• mesogens
• -ray diffraction