Novel Annulated Triphenylene Discotic Liquid CrystalsGenerated by Pictet-Spengler Cyclization

Abstract

Triphenylenes have been frontrunner in discotic liquid crystalline materials since their discovery. They possess great richness of mesomorphism in them. Chemists have been exploring this potential quite often by some substitutions in the core or periphery of the triphenylene molecule. In this current report, we extended the triphenylene ring system by fusing with nitrogen and studied their mesomorphic and optical properties. Four new compounds are prepared using Pictet‐Spengler cyclization of hexaalkoxytriphenylene‐1‐amine with various aldehydes. All the new compounds are well characterized using spectral and elemental analysis. Their mesomorphic properties are evaluated using polarizing optical microscopy, differential scanning calorimetry and X‐ray diffractometry. These derivatives showed columnar hexagonal phase with great promise for further studies.