Nematogenic homologous series of coumarin derivatives containing azomethine-ester linkages: synthesis, characterisation, photophysical and mesomorphic properties

ABSTRACT

Novel Homologous series of coumarin based Schiff’s base derivatives derived from 4’-formyl phenyl 7-n-alkoxycoumarin-3-carboxylate and 4-n-(decyloxy)aniline have been synthesised. The proposed structures of all the newly prepared compounds were confirmed by FT-IR, ¹H-NMR, ¹³C-NMR and elemental analysis. The photophysical properties of the coumarin based Schiff’s base derivatives have been studied. The textures of coumarin based Schiff’s base derivatives and their transition temperature were observed and recorded under a polarising optical microscope. The enthalpy change data were measured using Differential Scanning Calorimetry. By varying the alkoxy group (n = 1–10, 12, 14, 16) at the terminal position at one end of the moiety, the nematic phase was observed on heating as well as cooling. The thermal stability of all the compounds was recorded using thermal gravimetry analysis.

Graphical abstract

KEYWORDS:

• Mesomorphic
• coumarin
• nematic
• Schiff’s-base

Acknowledgments

The authors are thankful to the Head, Applied Chemistry Department, Faculty of Technology and Engineering, The Maharaja Sayajirao University of Baroda, Vadodara, Gujarat, India for providing the facility to carry out the research work. The Authors are also thankful to the SHODH (Scheme of Developing High-Quality Research) from Govt. of Gujarat for their financial support in research work. We would like to thank the team of the Heavy Water Plant, Baroda for providing ¹H and ¹³C-NMR analysis. We would like to thank the Head of the Chemistry Department, Faculty of Science, The Maharaja Sayajirao University of Baroda, Vadodara for helping us out with the DSC analysis.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Supplementary data

Supplemental data for this article can be accessed online at https://doi.org/10.1080/02678292.2024.2324462