Lateral Substituents Research Articles

The influence of bromine substitution and linking groups on the phase behaviour of light-responsive rod-like molecules

The effect of aromatic core bromination as well as different linking groups on the phase behaviour of light-responsive rod-like liquid crystalline materials is reported. For this purpose, two new series of laterally brominated rod-like molecules are designed and synthesized. The two series have three benzene rings connected using different linking groups either azo or ester units with different directions. Both series have pentyloxy chain at one end and an octyl chain at the other end in the first group or an octyloxy chain in the second group of materials. Additional lateral bromine substituent was inserted at ortho position with respect to the pentyloxy chain. The molecular self-assembly of the new materials was investigated using polarized optical microscope (POM), differential scanning calorimetry (DSC) and X-Ray diffraction (XRD). Depending on the type of the terminal chain (octyl or octyloxy) at one end and nature of the linking groups nematic phases as well as smectic C phases are observed, with variable temperature ranges. Interestingly, the nematic phases were found to exhibit cybotactic clusters with tilted SmC or orthogonal SmA structure (NCybC or NCybA) with wide temperature ranges. Finally, the isothermal photo switching because of cis–trans photoisomerization was investigated in solution as well as between different liquid crystal phases. This report could be of interest for optical information storage device applications.

Effect of lateral substituents on the properties of polymerisable liquid crystals with bistolane core

ABSTRACT A new series of polymerisable liquid crystals based on bistolane core and different lateral substituent groups (F, Cl, CH3 and C2H5) were synthesised and characterised by1H-NMR and13C-NMR. The properties of these compounds were tested by DSC, POM and Abbe refractometer. The results indicate that all of these compounds display a stable nematic phase, and the introduction of lateral substituents has a significant impact on the phase behaviour and birefringence. As the size of lateral substituents gradually increases the clearing point and birefringence of the liquid crystals both show a decreasing trend. The birefringence of these new compounds reaches 0.36 ~ 0.49, which is about 2 ~ 3 times that of the commercial compounds RM257. These new polymerisable liquid crystals with extremely high birefringence provide a choice for developing devices based on planar optics.

Effect of Alkyl Side Chains in BDT and 2D‐BDT Small‐Molecules as Donor Materials for Vacuum‐Processed Organic Photovoltaic Devices

Nine molecules based on benzo[1,2‐b:4,5‐b′]dithiophene (BDT) and 2D‐BDT derivatives are studied as donor materials in organic photovoltaic (OPV) devices fabricated by thermal evaporation, aiming to understand how different alkyl lateral substituents affect the molecular packing, the charge transport, and, subsequently, the device performance. Synthesis of the molecules is followed by a comprehensive characterization using thermal and differential scanning calorimetry analyses, which confirm their thermal stability and suitability for vacuum‐processed OPV devices. Thermal analysis also demonstrates a strong correlation between the melting point reduction of the molecules and the disorder caused by the alkyl chains. As the synthesized molecules present similar optical properties, the differences in the device performance are caused by the different substituents. BDT derivatives with low melting point temperatures produce reduced current density, hole mobility, and overall device performance, which are attributed to poor molecular packing. Additionally, energy‐dispersive X‐ray spectroscopy analysis suggests phase separation with fullerene, further impacting the efficiency of the devices. The findings indicate that the photovoltaic performance of BDT‐based molecules can be modulated by avoiding aliphatic substituents, providing a strategy for the design of more efficient materials, with thermal evaporation as an ideal method to evaluate and decouple molecular packing from solubility.

Mesomorphic and optical properties of azo-ester liquid crystalline reactive mesogens with enhanced thermal stability

A series of azo-ester-linked polymerizable liquid crystalline compounds M1-M3, containing lateral methyl substitution and different terminal alkoxy substituents, e.g., −OCH3, −OCH2CH3, and −OCH2CH2CH3 have successfully been synthesized and characterized. The chemical structures of the prepared compounds were confirmed by different spectroscopic techniques. Thermogravimetric analysis revealed that all the compounds exhibited excellent thermal stability and showed two-staged decomposition patterns. The optical microscopic study revealed that all compounds displayed only the nematic phase and lateral substituent played a crucial role in the formation of single mesophase. The broad X-ray scattering peaks for M1, M2, and M3 in the 2.5–5.5 nm−1 region was observed at temperatures of 154 °C, 85 °C, and 129 °C, respectively, upon cooling from the isotropic liquid, confirming the existence of nematic mesophase. The electronic spectra of M1-M3 showed two main absorption bands with λmax ranges of 263–266 and 369–377 nm. The E-Z photoisomerization study of M1-M3 showcased that the processes followed the first-order kinetic, and the isomerization rate decreased as the alkoxy chain length increased. On the contrary, the Z-E thermal isomerization rates for M1-M3 showed insignificant changes as the alkoxy chain length increased.

New self-organised benzo[b]thiophene-based materials for GHz applications

ABSTRACT This research delves into the synthesis and characterisation of novel liquid crystal compounds derived from benzo[b]thiophene cores, focusing on their potential applications in microwave technology. Two synthetic strategies were developed to construct rigid cores, resulting in the successful synthesis of 10 compounds with varied terminal groups and lateral substituents. Correlations between molecular structure and mesomorphic properties were elucidated through extensive comparative analysis. Birefringence measurements and quantum chemical calculations further provided insights into the optical properties and polarisability anisotropy of the synthesised compounds. The results highlight the influence of structural diversity on the compounds’ suitability for microwave applications. Specifically, compounds featuring carbon–carbon triple bonds and polar terminal groups demonstrated enhanced birefringence and polarisability values, indicating their potential in microwave device fabrication. This study underscores the importance of molecular design in optimising liquid crystal materials for advanced technological applications.

Ultrafast and Quantitative FRET Sensitization of Singlet Fission in Solution‐Processable Para‐Azaquinodimethane Films

AbstractIn this work, a green protocol for the synthesis of new para‐Azaquinodimethane (pAQM) small molecules, functionalized with anisole (An) or bithiophene (TT) moieties on the central unit and with different alkoxy groups as lateral substituents is developed and reported. The alkoxy lateral substituents are found to strongly impact the solubility and processability of the chromophores. On the other hand, the steady–state and time‐resolved spectroscopic results show completely different spectral and photophysical features for the An‐ and TT‐ derivatives. Only for the TT‐compounds, the nanosecond and femtosecond transient absorption experiments reveal low efficiency of triplet production in solution as well as ultrafast (≈1 ps) and efficient (≈200%) singlet fission (SF) in thin film. The yellow An‐containing molecules are instead used to sensitize the purple SF‐active TT‐compounds via quantitative FRET in mixed thin films, which interestingly exhibit panchromatic absorption extending in the entire visible spectral range. With this study, the synergy between FRET and SF is exploited at the intermolecular level in the solid‐state for the first time by considering unconventional and stable SF chromophores, opening intriguing new possibilities for solar energy harvesting.

Polymers with one free gallic acid per monomer unit. Controlled synthesis and intrinsic antioxidant/antibacterial properties

The development of bio-based thermoplastics is rapidly growing due to the depletion of fossil fuel reserves but also in the hope of obtaining polymers with original properties. Herein, we report the controlled synthesis of original homopolymers derived from gallic acid, one of the well-known natural polyphenols that exhibits various health-promoting effects. More precisely, acrylate, methacrylate and acrylamide monomers based on a protected gallic acid are firstly obtained by a rethought multistep scheme. Then, a controlled photo-mediated RAFT (Reversible Addition Fragmentation chain Transfer) polymerization is carried out before a final deprotection. By this way, original polymers bearing a free gallic acid as a lateral substituent on each monomer unit are described. The intrinsic antibacterial and antioxidant properties of these polymers are highlighted and compared with those of gallic acid.

Effect of Laterally Substituted Methoxy Group on the Liquid Crystalline Behavior of Novel Ester Molecules

Background: The aim of this research is to study the effect of length-to-width ratio on mesomorphism to enhance the understanding of its potential applications. This will be achieved by synthesizing a unique and innovative series of identical ester molecules, including lateral methoxy groups and terminal ethyl benzoate groups. In this research, we aim to find new insights into the relationship between molecular structures and mesomorphic behaviors, which could have significant implications for the development of advanced materials with adapted properties. : The objective of the study is to investigate the mesophase behavior of new ester mesogens and determine how they are influenced by lateral methoxy groups. By identifying the underlying perspectives and relationships between these variables, we hope to better understand the unique properties and potential applications of these materials. Method: In this research work, the focus is on the synthesis of ethyl(E)-4-((3-(4-alkoxy-3- methoxyphenyl)acryloyl)oxy)benzoate, which is prepared from Steglich esterification method by using (E)-3-(4-alkoxy-3-methoxyphenyl)acrylic acid and ethyl 4- hydroxybenzoate. Synthesis processes involve precise reaction sequences designed to ensure maximum yield and purity of the final product. By providing a detailed report on the experimental process, this study contributes to the ongoing research efforts aimed at the development of innovative compounds with various applications in liquid crystals Result: A new set of liquid crystal derivatives has been synthesized and studied to investigate the effect of molecular structure on the behavior of liquid crystals, with particular attention to the group -OCH3 located laterally. This series was composed of 12 derivatives (C1-C16). Among them, the first six derivatives (C1-C6) did not have the characteristics of a liquid crystal, while the remaining derivatives (C7 and C8) had a monotropic behavior, and C10-C16 had an enantiotropic smectogenic liquid crystal behavior without exhibition of the nematic phase. The average thermal stability of the smectic property was 87.33 °C, and the mesophase range was 2 °C to 14 °C. The molecular structure was confirmed by analytical and spectral analysis. The properties of liquid crystals of this new series were compared with those of other known structurally similar homologous series. The transition temperatures were determined with an optical polarizing microscope equipped with a heating phase. Conclusion: The mesomorphic thermal and optical properties of the compounds have been validated by DSC and POM techniques. The result shows that the length of the alkyl chain has a significant influence on the mesomorphic characteristics and thermal stability of the different mesophases. Evaluation of the compounds studied indicates that the molecules are sensitive to their lateral substituent, which influences the thermal characteristics and stability of the mesophase.

High-Δn tolane-liquid crystal diluters with low melting point and low rotational viscosity

High birefringence (Δn) and low melting point (Tm), high Δn and low rotational viscosity (γ1) are two pairs of contradictory performance parameters. In this work, two high-Δn LC diluters 3PTPF2V and 3PTPFOV are proposed to achieve a fine balance between them. These target compounds containing a rigid tolane core, a lateral fluorine substituent and a buty-3-enyl or allyloxy terminal group were further synthesized. Some experimental instruments, such as POM, DSC, Abbe refractometer, multi-channel liquid crystal evaluation system, were adopted to investigate their properties of mesomorphic phase behavior, Tm, Δn and γ1 by comparing with classical LC diluters 3HHV and V2PTP2V. Meanwhile, density functional theory (DFT) calculations were employed to correlate the experimental results, and their comprehensive effects on two high-Δn LC mixtures were further evaluated. Research results indicated that both target compounds possess low Tm (∼20 °C), low γ1 (∼6.5 mPa·s), and high Δn (>0.26). Performance in high-Δn LC mixture demonstrated that they could effectively decrease Tm and γ1, meanwhile maintain high Δn and Tc values, meaning their potential application prospects in fast-response LC optical devices.

Chiral recognition without π−π-interactions: Highly efficient chiral strong cation exchangers lacking an aromatic unit in the molecular structure

Current state-of-the-art chiral stationary phases (CSPs) enable chiral resolution of almost any racemic mixture of choice. The exceptions represent ionizable and ionized substances that fail at any attempts to resolve on commercially available CSPs. These compounds, however, can be efficiently separated on chiral ion exchangers. Commercially available Cinchona alkaloids-based chiral weak ion-exchangers are typically used for chiral resolution of organic acids, while zwitterion ion-exchangers are efficient in the resolution of acids, bases, and zwitterions. The latter possess in their structure a cation exchange unit, which alone can serve as a cornerstone of chiral strong cation exchangers facilitating chiral separation of various basic racemic mixtures.Although chiral strong cation exchangers (cSCX) are efficient CSPs, their structural variations have not been thoroughly studied so far. It was assumed that the mechanism of chiral recognition of basic compounds by cSCX is based predominantly on π-π-interactions, hydrogen bonding and steric interactions (CSP I). To verify this assumption, we aimed in our study on the design and synthesis of cSCX first lacking lateral polar substituents on the aromatic unit in the selector's structure (CSP II), and second, to replace the aromatic unit by a cyclohexane ring (CSP III and IV), thereby to omit completely the π-π-interactions. We hypothesized that this structural change should lead to a partial or complete loss of enantiorecognition power of the selectors. Surprisingly, the non-aromatic cSCXs have shown chiral recognition capability comparable to that of previously described chiral cation exchange-type CSPs: from 16 analytes screened, 11 analytes were baseline resolved and 5 partially resolved on CSP I, while non-aromatic CSP III resolved 10 analytes baseline and 6 partially.We discuss the structural motifs of the known cSCX and the novel non-aromatic selectors in a relationship with their chromatographic performance using a set of basic analytes. Moreover, we present a theory of an effective chiral recognition mechanism by two novel non-aromatic cSCXs based on the chromatographic results and quantum mechanical calculations.

The influence of molecular shape and electronic properties on the formation of the ferroelectric nematic phase

ABSTRACT The synthesis and characterisation of two series of ferroelectric nematogens based on RM734 having an additional methoxy group on the central phenyl ring are reported, the 3-methoxy-4-((4-nitrophenoxy)carbonyl)phenyl 2-alkoxy-4-alkoxybenzoates (7-m-n) and the 3-methoxy-4-((3-fluoro-4-nitrophenoxy)carbonyl)phenyl 2-alkoxy-4-alkoxybenzoates (8-m-n). In order to compare the behaviour of these series to those of the corresponding materials that do not contain the methoxy group on the central phenyl ring, we also report the synthesis and characterisation of 4-[(4-nitrophenoxy)carbonyl]phenyl 4-methoxybenzoate (11-0-1), 4-[(3-fluoro-4-nitrophenoxy)carbonyl]phenyl 4-methoxybenzoate (12-0-1) and 4-[(3-fluoro-4-nitrophenoxy)carbonyl]phenyl 2,4-diethoxybenzoate (12-2-2). Two compounds in which a lateral ethoxy chain is attached to the central ring, 3-ethoxy-4-[(4-nitrophenoxy)carbonyl]phenyl 2,4-dimethoxybenzoate (18-2-1) and 3-ethoxy-4-[(3-fluoro-4-nitrophenoxy)carbonyl]phenyl 2,4-dimethoxybenzoate (19-2-1), are also described. The behaviour of these materials shows that the relative stabilities of the ferroelectric nematic, NF, and conventional nematic, N, phases are governed by a subtle interplay of steric and electronic factors. Furthermore, the electronic factors are better understood in terms of isolated regions of electron density rather than by a single large longitudinal dipole moment. In terms of molecular shape, to observe the NF phase it appears that the molecular structure must include one or more lateral substituents that enhance molecular biaxiality and destabilise the N phase.

Influence of the length of end-group double bond substituents on the temperature change of phase transition in liquid crystals

ABSTRACT A series of nematic liquid crystal (LC) monomers, containing a reactive group in the lateral substituent, were designed and synthesised through an organic synthesis reaction. Considerable changes were made to the properties of the liquid monomers by varying the terminal alkyl chain lengths. The molecular structures of the intermediates and the LC monomers were characterised by flourier infrared absorption spectrometry and proton nuclear magnetic resonance (1H NMR) spectroscopy, leading to the identification of the target product. The phase transition temperatures of the LC monomers were observed and analysed using differential scanning calorimetry (DSC) and polarising optical microscopy (POM) with a hot stage. The two-way thermotropic liquid crystalline behaviour was observed during the heating process, providing insight into the effect of substituent changes on the phase transition temperature.

Photophysical properties of 3-arylthioimidazo[1,2-a]pyridine derivatives: The role of peripheral electron-donating and electron-withdrawing groups in the advance of organic materials engineering

3-Arylthioimidazo[1,2-a]pyridine derivatives may present potential use in fields such as optoelectronics, organic light-emitting diodes (OLEDs), bioimaging, and may be employed as bioprobes in DNA and RNA. However, before these materials can be used for such applications, it is necessary to assess their photophysical properties. Here, we investigated the photophysical properties of five novel 3-arylthioimidazo[1,2-a]pyridine derivatives with different peripheral electron-withdrawing and electron-donating groups. The use of spectroscopic techniques, including UV–vis absorption, fluorescence, time-resolved fluorescence spectroscopy, combined with quantum chemical calculations, allowed us to gain a comprehensive understanding of the compounds' photophysical properties. The results revealed that the 3-arylthioimidazo[1,2-a]pyridine derivatives possess remarkable emissive properties, with a 4.5-fold increase when substituting the trifluoromethyl group for a methoxy group. Furthermore, it has been observed that the compounds containing peripheral groups with halogen atoms exhibit fluorescence quenching. The electron-withdrawing character of the imidazo[1,2-a]pyridine and the position of the lateral substituent hindered the impact of electron-withdrawing groups, while electron-donating groups enhanced the photophysical properties, resulting in increased Stokes shift, larger permanent dipole moment difference, and charge displacement. In conclusion, this study provides key insights into the photophysics of 3-arylthioimidazo[1,2-a]pyridine derivatives and the role of peripheral electron-donating and electron-withdrawing groups. These findings hold great potential for the advancement of optical materials and set foundation for future technological applications.

Effect of substituents on the properties of fluorine-containing polyphenyl liquid crystal compounds

In order to explore the influence of molecular structure on the properties of liquid crystal (LC) materials, the dielectric anisotropy, rotational viscosity coefficient and birefringence of different fluorine-containing polyphenyl LC compounds are measured experimentally. The effects of lateral substituents and terminal substituents are analyzed. The experimental results show that the substitution of fluorine substituents in lateral substituents or terminal substituents will lead to the decrease of rotational viscosity coefficient, whether it is fluorine-containing triphenyl LC compounds or fluorine-containing tetraphenyl LC compounds. The dielectric anisotropies of LC compounds (fluorine-containing tetraphenyl LC compounds ND-3 and ND-8, ND-4 and ND-9, and ND-1 and ND-10) in which the terminal isothiocyano substituents are substituted by fluorine substituents all show a downward trend, with the decreasing degrees of 41.3%, 20.7% and 19.2% respectively. In addition to the influence of the replacement of fluorine and isothiocyanato on the terminal substituents, the dielectric anisotropy is affected by different lateral substituents from large to small: fluorine, methyl, and ethyl. The lateral fluorine substitution impact of ND-3, with an increase of 9.4%, is the best among fluorine-containing tetraphenyl LC compounds when compared to the lateral ethyl substitution of ND-2. Besides, compared with -F, -NCS can effectively extend the π-electron conjugation length of the molecule and improve the birefringence of the LC. This research is of great help to improve the comprehensive properties of LC materials and provides data accumulation for the development and application of LC compounds.

Synthesis and properties of biphenyl liquid crystal diluters terminated by 2,2-difluorovinyloxyl for high birefringence liquid crystals

ABSTRACT A series of liquid crystal (LC) diluters containing a rigid biphenyl core with a lateral fluorine substituent, a 2,2-difluorovinyloxyl terminal group and a flexible n-alkyl chain were designed and synthesised through classical organic synthetic reactions. Their chemical structures were characterised and confirmed by traditional methods. Meanwhile, the effects of alkyl-chain length, terminal group and lateral fluorine substituent on the melting point (T m), birefringence (Δn), dielectric anisotropy (Δε) and rotational viscosity (γ 1) of LC diluters were investigated. Density functional theory (DFT) calculations were employed to obtain the molecular polarisability, dipole moment, frontier orbitals, biphenyl dihedral angle and aspect ratio. Furthermore, their comprehensive properties in low-Δn LC mixture 002 and high-Δn LC mixture P01-F were further evaluated, and it was found that the 2,2-difluorovinyloxyl LC diluter 3FV have a significant advantage in reducing the T m and γ 1 of LC mixtures, and increasing the values of Δn and Δε. The research results provide technical support and theoretical guidance for the molecular design of new LC diluters and the development of fast response liquid crystals.

Design and synthesis of benzofuran- and naphthalene-fused thiazinones as antimycobacterial agents.

Benzothiazinones (BTZs) have widely inspired medicinal chemistry and translational research due to their remarkable antitubercular potency and clinical potential. While most structure-activity relationship campaigns have largely focused on lateral chain modifications and substituents on the BTZ core, scaffold hopping strategies have been rarely investigated previously. In this work, we report the first example of ring expansion of the BTZ core toward benzofuran- and naphthalene-fused thiazinones. In vitro testing showed micromolar activity for both compounds, and molecular docking simulations provided insights into their reduced inhibitory capacity toward the enzymatic target (DprE1). Calculated electrochemical potentials revealed a lower susceptibility to reduction as opposed to BTZ drug candidates, in line with the mechanistic requirement for covalent binding.

Synthesis and performance evaluation of fluorinated biphenyl diluters for high birefringence liquid crystals

ABSTRACT Liquid crystal (LC) mixtures with high birefringence (∆n) and low rotational viscosity play an essential role for fast-response LC devices. However, high birefringence and low rotational viscosity are a pair of contradictory performance parameters. In this work, two high-∆n LC diluters are proposed to achieve a fine balance between them. These two terminal olefin diluters containing a rigid biphenyl core with a lateral fluorine substituent, a buty-3-enyl terminal group and a flexible n-alkyl chain were designed and synthesised through classical organic synthetic reactions. Meanwhile, their comprehensive properties were further evaluated in a LC mixture P02-F containing fluoro-tolane and a LC mixture P12-ISO containing isothiocyano-tolane. The results show that the biphenyl diluters 2BBF2V and 3BFB2V could effectively decrease the T m of LC mixture P12-ISO to below −25°C, while maintain high ∆n and large Δε, which are suitable for the high-∆n LC mixtures containing isothiocyano-tolane. Furthermore, DFT calculations of molecular conformation and polarisability components were utilised to correlate the experimental findings.

Extended π-Conjugation and Structural Planarity Effects of Symmetrical D-π-A-π-D Naphthalene and Perylene Diimide Semiconductors on n-Type Electrical Properties.

A series of Donor-π-Acceptor-π-Donor (D-π-A-π-D) compounds based on naphthalendiimide (NDI) and perylenediimide (PDI) central cores combined with triphenylamine and phenylcarbazole donor groups have been synthesized, characterized and tested in top-contact/bottom gate organic field-effect transistors (OFETs). The results showed high electron mobilities, up to 0.3 cm2V-1s-1, in the case of NDI derivatives and moderate values of around 10-3 cm2V-1s-1 for PDI-based semiconductors. Quantum chemical calculations were performed in order to support the experimental data. The results suggest that adequate molecular characteristics and larger crystalline domains in NDI vs. PDI semiconducting films may be the reasons behind the enhanced electrical properties of NDI derivatives. Furthermore, when the lateral donor substituents are triphenylamine groups, the mobilities were slightly higher in comparison to phenylcarbazole donor groups due to an improved electron-donating character. Other characterization techniques such as AFM, X-ray diffraction or spectroelectrochemistry, among others, have been performed to analyze supramolecular order, charge carriers' nature and stability, parameters closely related to charge transport characteristics.

Synthesis and Mesomorphic Properties of New Non-symmetric Liquid Crystal Dimers

Abstract: New non-symmetric liquid crystal dimers, N-(4-(n-(4-(benzothiazol-2-yl)phenoxy) alkyloxy) benzylidene)-2,4-difluoroaniline (DSFCn), containing two mesogenic core units of benzothiazole and benzylideneaniline were reported. The core system was connected by a flexible alkyl spacer, -(CH2)n-(where n =2-6, 8, 10, and 12). The spectroscopic techniques were employed to confirm the molecular structure of the title compounds. Differential scanning calorimetry and polarizing optical microscopy were used to study the mesomorphic properties of the synthesized compounds. Observation under crossed polarized light reveals that compounds (n = 4, 5, 6, 8, 10, 12) are purely nematogens. The nematic phase in the dimers are caused by the presence of the lateral fluorine atoms at the benzylideneaniline core. Mesophase thermal stability has been suppressed significantly by the fluorine atom at the lateral position which increased the molecular breadth and subsequently, results in weaker overall lateral intermolecular attraction. The structure-property relationships of the dimers were inferred through comparison of thermal properties of the present dimers with those of the earlier reported analogous that do not possess any lateral substituents.

Balance the trade-offs between high birefringence, large dielectric anisotropy and low viscosity in nematic liquid crystals through molecular splicing strategy

ABSTRACT A series of liquid crystals containing one n-propyl/n-propoxy, lateral fluorine substituent, a tolane mesophase unit, and a 2,2-difluorovinyl terminal group were designed and synthesised. Their chemical structures were characterised and confirmed by nuclear magnetic resonance (NMR), mass spectrometry and Fourier transform infrared spectrometry (FTIR) instruments. Meanwhile, the position and number effects of lateral fluorine substituents on the thermal, mesomorphic, and electro-optical properties of these compounds were explored. Furthermore, density functional theory (DFT) calculations of molecular conformation, polarisability components and dipole moment were utilised to correlate the experimental results. Research results show that the 2,2-difluorovinyl-terminated liquid crystal compounds possess excellent properties of low melting point, wide nematic-phase temperature interval, high birefringence, large dielectric anisotropy and low rotational viscosity. This molecular splicing strategy is an effective method to balance the trade-offs between high birefringence, large dielectric anisotropy, and low viscosity in nematic liquid crystals.