A series of novel naphthophenanthridine derivatives are synthesized via N-annulation of hexabutoxytriphenylene-1amine with various aliphatic aldehydes through the Pictet− Spengler reaction. The synthesized derivatives have been found to self-assemble into a columnar hexagonal mesophase over a wide temperature range, as validated through polarized optical microscopy, differential scanning calorimetry and X-ray diffraction experiments. The photophysical properties of these compounds were studied using UV−visible and emission spectroscopy. The synthesized compounds exhibit ambipolar charge transport, showing temperature-independent electron and hole mobility on the order of 3 × 10 −4 cm 2 /V s, as evaluated by the time-of-flight technique. These novel N-annulated derivatives can be of immense potential toward semiconducting applications of self-assembling supramolecular systems.

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.

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Columnar mesogens constitute a fascinating class of supramolecular nano‐architectures owing to the exceptional properties induced by their self‐assembling behavior. Extending the π‐conjugated core in such systems by incorporating heteroatoms extensively influences their mesomorphic, photophysical properties, etc., presenting them as potential candidates for optoelectronic applications. In the present work, a series of novel nitrogen and oxygen‐incorporated chromenonaphthophenanthridine‐based elliptical dimers have been synthesized through tandem Pictet‐Spengler cyclization followed by ipso‐aromatic substitution in one‐pot. Mesophase characterization has been carried out by employing POM, DSC, and X‐ray diffraction studies. Photophysical properties were investigated using UV‐vis and emission spectroscopy. Furthermore, the charge transport properties were analyzed by time‐of‐flight measurements, and the observed ambipolar mobilities were found to be of the order of 10−3 cm2 V−1 s−1. The high solubility, excellent thermal stability, self‐organizing properties, and ambipolar charge transport characteristics make them promising candidates for applications in organic electronics.