“Synthesis, Mesomorphic and DFT Studies of Chalcone Derived Room Temperature Liquid Crystal with Presence of Lateral Nitro and N, N-Dimethyl Amino Terminal Group”

Abstract

In this present article, we wish to report on the liquid-crystalline properties of chalcone-ester based homologous series of compounds having aliphatic chain length in n-alkoxy group (n = 1 to 10, 12, 14, 16, 18). The present series consisted thirteen compounds, in which comp.C₁ and C₂ shows nonliquid crystalline properties, while comp.C₃ to C₇ display SmC phase and comp.C₈ to C₁₈ exhibits only nematic phase. Textural pattern of presently synthesized compounds are schlieren and threaded type. All this compounds were well characterized by elemental analysis, FT-IR and ¹H NMR. Phase transition temperatures of present synthesised compounds were determined by optical polarising microscopy (POM), differential scanning calorimetric (DSC). Detailed XRD investigation endorses the presence of the nematic phase in higher homologues and SmC phase in lower homologues. It is shown that chalcone with ester as linking unit favors a calamitic liquid crystalline behaviour in molecules. To get more insights, the DFT based HOMO, LUMO studies are carried out which supports intramolecular charge transfer interactions in this class of mesogens. Chalconyl ester based compounds C₃ to C₁₂ shows antibacterial as well as antifungal activity compared with corresponding standard drugs.

Graphical Abstract

Key Words:

• Liquid crystal
• nematic
• chalcone
• enantiotropic

Acknowledgement

DS and RBP acknowledge thanks to Dr. R.R.Shah, principal and management of K. K. Shah Jarodwala Maninagar Science College, Ahmedabad for providing research lab and other facility. VS and VP thanks to Department of Chemistry, Faculty of Basic and Applied Science, Sirohi, Rajasthan for providing lab facility. Authors thanks to Mr.Anuj Patel for providing DFT study of present synthesized compounds. Authors are also thankful to NFDD Centre for providing analytical and spectral services.