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# Combining discotic mesogens with AIE luminogens for advanced optoelectronic applications: Design, synthesis, mesomorphism, self-assembly and optical properties of tetraphenylethylene-triphenylene oligomeric conjugates

Hang Lin<sup>a</sup>, Ke-Xiao Zhao<sup>a</sup>, Bi-Qin Wang<sup>a</sup>, Ping Hu<sup>a</sup>, Ke-Qing Zhao<sup>a,*</sup>, Bertrand Donnio<sup>b,*</sup>

**Keywords:** Tetraphenylethylene, Triphenylene, Columnar mesophase, Supramolecular gels, Aggregation-induced emission, Photodetection

The combination of different molecular entities with their own and specific functionalities within a single molecule enables the generation of potentially original multifunctional materials with unique properties and a broad range of applications across various fields. In this work, tetraphenylethylene (TPE) and triphenylene (TP) molecules are combined within a single oligomeric structure to yield original mesomorphic materials: TPE was chosen for its exceptional optical properties (AIE—aggregation-induced emission), while TP was included to ensure columnar self-assembly and mesomorphism. Two tetraphenylethylene-triphenylene tetrads, **TPE-TP4** and **TPE-ThTP4**, with a crossed-shaped molecular structure, with the central TPE connecting 4 radial TP subunits, have been synthesized by the Suzuki-Miyaura coupling reaction. Both compounds exhibit high thermal stability, above 340°C. While **TPE-TP4** shows only crystalline behaviour before reversibly melting into the isotropic liquid, **TPE-ThTP4**, which includes an additional thiophene ring bridging the central TPE and the peripheral TPs, exhibits

<footnote><sup>a</sup>College of Chemistry and Material Science, Sichuan Normal University, Chengdu 610066, China</footnote>

<footnote><sup>b</sup>Institut de Physique et Chimie des Matériaux de Strasbourg, UMR 7504 (CNRS-Université de Strasbourg), Strasbourg 67034, France</footnote>

<footnote>* Corresponding authors at: Institut de Chimie et Physique des Matériaux de Strasbourg, UMR 7504 (CNRS-Université de Strasbourg), Strasbourg 67034, France and College of Chemistry and Material Science, Sichuan Normal University, Chengdu 610066, China.

E-mail addresses: kqzhao@sicnu.edu.cn (K.-Q. Zhao), bertrand.donnio@ipcms.unistra.fr (B. Donnio).

Received 11 March 2025; Received in revised form 6 May 2025; Accepted 16 May 2025</footnote>
a rectangular “multicolumnar” phase (Col<sub>rec</sub>), over a large temperature range of approximately 300°C. They also both self-assemble in fibers when mixed in various solvents to form organic gels. UV-visible absorption and fluorescence emission spectra reveal that both compounds have strong fluorescence properties in solutions and thin films, with emission wavelengths ranging between 460 and 550 nm. The absolute emission quantum yield is highly solvent-dependent, reaching a maximum of 84.5 % in cyclohexane. These tetrameric compounds also present aggregation-induced emission behaviour with a significant enhancement of the fluorescence intensity. Overall, the combination of discotic mesogens and AIE-gens within a single molecular framework holds great promises for the development of next-generation optoelectronic materials.

# 1 Introduction

The study of the structure-property/activity relationships of functional liquid crystals is a key topic in current materials science research, particularly for improving the design of systems that incorporate optically and electronically active constituents for applications in organic electronics, sensors, and light-emitting devices [1,2]. While the emergence of liquid crystalline phases in geometrically constrained systems can be guaranteed through adapted molecular design [2], the combination of protomesogenic molecules with structurally diverse and complex functional chemical species, often with incompatible molecular structures, nevertheless makes it difficult to preserve the organizational behaviour, and to predict intrinsic physical properties, as well as stability under thermal, optical or chemical stresses. Hence, a comprehensive and systematic exploration of the molecular diversity in liquid crystals, guided by various molecular design paradigms, remains a critical and indispensable research challenge. This approach not only enhances our understanding of the fundamental principles governing the behavior of liquid crystals, but also fosters the development of new materials with customized properties for a wide range of advanced technological applications [1,2].

Discotic mesogens, organic molecules with a disc-like aromatic structure surrounded by aliphatic chains, usually self-assemble into columnar phases when arranged in a liquid-crystalline state [1–3]. The extension of $\pi$-conjugation, the size and degree of planarity of the aromatic cores, which govern $\pi-\pi$ interactions, concomitantly with the peripheral flexible chains (nature, length, topology), which control van der Waals forces, determine their thermodynamic behaviour and self-assembly into columnar mesophases. Furthermore, such supramolecular arrangements allow one-dimensional charge transport, making them highly desirable in optoelectronic applications [4–9]. The regularity of the self-assembled structures indeed facilitates both the control of the molecular packing and the long-range order, key features that improve the performance of devices like organic light-emitting diodes (OLED), field-effect transistors (OFET), and solar cells (OSC). However, in practical applications, luminescent liquid crystal molecules are mostly found in aggregated states (e.g., in thin films) and often suffer from low emission efficiency due to aggregation-caused quenching (ACQ) phenomena. ACQ effect is essentially due to the suppression of intramolecular vibration and rotational relaxation which dissipate energy from the excited

state through non radiative energy transfer processes, resulting in the weakening or quenching of the luminescence [10–15]. In contrast, the key of aggregation-induced emission (AIE) [16,17] effect is the restriction of intramolecular rotation in the aggregated state, which reduces non-radiative decay pathways that usually cause fluorescence quenching. This characteristic has prompted interest in combining mesogenic materials with prototypical AIE luminogens, such as 1,3,5-triazine [18], cyanodistyrene [19,20], tetraphenylthiophene [21], tetraphenylethylene [22–29], that maintain or even enhance their emission upon aggregation, whilst in the mesomorphic state [18–31]. Thus, the integration of AIE-active unit within discotic systems may offer interesting potential to create and develop novel luminescent materials that exhibit columnar mesomorphism with promoted charge transport and enhanced fluorescence in the aggregated state, significantly improving the performance of optoelectronic, lighting, display, and bio-imaging devices [16,17,30,31]. The synergy between self-assembly and optical properties further enables the development of multifunctional materials with stimuli-responsive properties, which can be applied in molecular sensing and detection. In fact, the emission characteristics of AIE-gens can be modulated by external factors such as temperature, pH, or the presence of specific analytes, making them promising candidates for biosensors that selectively detect specific molecular targets [16,17].

In this study, we report a new class of mesogenic tetraphenylethylene-triphenylene conjugates (TPE-TP) having a cross-like structure, consisting of four peripheral mesogenic TP units $\sigma$-bonded to a central TPE as the AIE-active unit. Two of such molecules were synthesized concisely and efficiently by the Pd-catalyzed Suzuki-Miyaura cross coupling reaction, namely TPE-TP4, where TP and TPE segments are directly linked by $\sigma$ bonds, and TPE-ThTP4, where these units are bridged through electron-rich thiophene rings (Th). While TPE-TP4 shows only a crystalline behaviour, TPE-ThTP4 exhibits a rectangular columnar phase (Col<sub>rec</sub>), over a large temperature range, right from room temperature. Both oligomers also form organic gels in nonpolar solvents. UV-visible absorption and fluorescence emission measurements show that both compounds have good fluorescence properties in solutions and thin films, and the emission wavelength is centred between 460 and 550 nm. The absolute emission quantum yields of the compounds is found to be solvent-dependent, with a maximum of 84.5 %
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**Scheme 1**

Star-like tetraphenylethylene-triphenylene tetrads **TPE-TP4** and **TPE-ThTP4**: molecular structures, synthesis, nomenclature and yields.

in nonpolar solvents. These tetrameric compounds also present aggregation-induced emission with a substantial increase of the fluorescence intensity.

**2 Results and discussion**

**2.1 Synthesis**

A reliable and efficient synthetic route was designed for the preparation of these two cross-shaped AIE compounds. The key intermediate triphenylene borate derivatives (**M5** and **M7**, Scheme 1) were prepared from the inexpensive 3,4-dimethoxybromobenzene and *o*-bromophenyl methyl ether as raw materials (see Scheme S1 in Supporting Information). The precursory tetramethoxybiphenyl derivative (**M2**) was obtained in two steps by $FeCl_3$-catalyzed homocoupling of 4-bromo-1,2-dimethoxybenzene, followed by debromination with *n*-BuLi. Subsequently, intermolecular Scholl oxidation cyclization reaction was carried out with *o*-bromophenyl ether in a dichloromethane solution of $FeCl_3/CH_3NO_2$ to yield the pentamethoxy substituted brominated triphenylene **M3**. **M3** was then fully demethylated with $BBr_3$ and totally re-etherified with hexylbromide under alkaline condition to generate 2-bromo-3,6,7,10,11-pentakis(hexyloxy)triphenylene (**M4**) with a yield of

ca. 70 % (overall yield of around 30 % for 5 consecutive steps of around 70-80 % each). This brominated triphenylene derivative expands the application possibilities in molecular design and synthesis of previously widely used monohydroxy triphenylene derivatives and expensive triflate triphenylene derivatives. On this basis, **M4** leads to the borate intermediate **M5** in one step by reaction with diboronic acid pinacol ester, and to **M7** [32] in a two-step procedure involving first Suzuki-Miyaura coupling with 2-thiophene borate to generate **M6**, followed by concatenation with *n*-BuLi and isopropanol pinacol borate to yield the other final intermediate triphenylene thiophene borate derivative **M7**. Finally, both **M5** and **M7** intermediates were then subjected to efficient Pd-catalyzed Suzuki-Miyaura cross-coupling reaction with commercially available tetra-(4-bromobenzene)ethylene, resulting in compounds **TPE-TP4** and **TPE-ThTP4** in 85 % and 54 % yield, respectively.

The specific synthesis details of intermediates and target compounds are detailed in the supporting information. The compounds were systematically characterized by nuclear magnetic resonance spectroscopy ($^{1}$H/$^{13}$C NMR, Figs. S1-S9), high-resolution mass spectrometry (HRMS, Figs. S10-S15), and elemental analysis (EA), and all these measurements
are consistent with the proposed molecular structure of the compounds.

## 2.2 Thermal stability

The thermal stability of both **TPE-TP4** and **TPE-ThTP4** compounds were assessed by thermogravimetric analysis (TGA, dynamic mode) prior to conducting further characterization of their thermal properties. The decomposition temperatures ($T_{dec}$), determined as the onset of a 5 % weight-loss, were observed at 345°C at **TPE-TP4** and 370°C for **TPE-ThTP4**, probing their excellent thermal stability (Fig. S16). The bridging thiophene rings likely enhance molecular conjugation and $\pi-\pi$ overlaps, which is coherent with the higher thermal stability of **TPE-ThTP4** compared to **TPE-TP4**. Subsequent characterizations including polarized optical microscopy (POM), differential scanning calorimetry (DSC), and small angle/wide angle X-ray scattering (S/WAXS) measurements were performed at temperatures below $T_{dec}$, in temperature ranges where the compounds are stable, ensuring thus complete reliability.

## 2.3 Thermotropic mesomorphism

The thermal behaviour of the tetrads was first studied by POM and DSC (Figs. S17-S20, Table S1 in Supporting Information). Typical defect textures were observed by POM when the compounds were heated above the clearing temperature and then slowly cooled from an isotropic liquid (Figs. S17-S18). When cooled, **TPE-TP4** exhibits a smooth, marble-like non-fluid texture, and the texture perpendicular to the glass substrate appears as a dark field due to its low transparency. After removing the polarizer, layered shadows can be observed, which suggests a crystalline phase (Fig. S19). In contrast, **TPE-ThTP4** exhibits a fluid, fan-shaped birefringent texture, and there is an optical dark field caused by the vertical orientation of partially stacked supramolecular columns with the glass substrate. When the polarizer angle changes from orthogonal to 60 °, due to optical anisotropy, the groove shaped optical dark field gradually brightens, pointing towards a columnar phase (Fig. S19). DSC thermograms (Fig. S20) showed only one endothermic peak, detected during the heating process for both tetrads, which, in consistency with POM, corresponds to the transition to the isotropic liquid state (i.e., transition temperatures on heating, at 166°C for **TPE-TP4** and at 320°C for **TPE-ThTP4**, Table S1). Similarly, on cooling, only one exothermic peak was detected, corresponding to the transition from the isotropic liquid to the liquid crystalline/crystalline state, also consistent with POM observations, with an important cooling effect for **TPE-TP4**, in agreement with a first-order transition to a crystalline phase. For the mesomorphic **TPE-ThTP4**, no sign of crystallization was seen down to room temperature nor on further heat-cool cycles. In **TPE-TP4**, the triphenylene units are directly connected by $\sigma$ bonds to the central TPE unit, generating significant steric hindrance between the TP subunits that strongly distorts the molecule out-of-the plane, as confirmed by DFT calculations (Tables S3-S4). Consequently, intermolecular interactions are drastically weakened, and, similarly to other large expanding PAHs [33,34], the self-assembly of the molecule into supramolecular columns is largely prevented. In contrast, the incorporation of thiophene bridges between the TP rings

and the central TPE, while inevitably leading to an increase in the molecular expansion of **TPE-ThTP4**, also enhances the rotational freedom of the four planar peripheral triphenylenes and significantly improves the molecular flexibility by removing the spatial constraints imposed by the twisted central aromatic nucleus (TPE). Moreover, the presence of thiophene rings also facilitates enhanced electronic conjugation within the tetrad molecule, strengthening intermolecular interactions. This, in turn, promotes the stacking of the triphenylenes into columns, as evidenced by the near-doubling of the clearing temperature (by ca. 168°C with respect to **TPE-TP4**), which reflects an improvement in the molecule's thermal stability and mesophase formation ability.

S/WAXS patterns, recorded at various temperatures for both compounds, confirm unequivocally the POM observations (Figs. 1 and S17-S21). The numerous diffraction peaks observed across the entire angular range, from room temperature up to the isotropic liquid (Figs. 1a and S21), confirm the absence of a conventional liquid crystalline mesophase for **TPE-TP4**. A “soft” crystalline phase can be formed instead, characterized by a long-range correlated three-dimensional lattice that encompasses molten regions as evidenced by the combination of wide-angle diffraction peaks of low intensity, superimposed with the broad

<figure><img src="image_5.png" /><figcaption>**Fig. 1**
S/WAXS patterns of **TPE-TP4** and **TPE-ThTP4** recorded on cooling from the isotropic liquid at various temperatures. The main three peaks of **TPE-ThTP4** correspond to reflections (20), (12) and (22) of a rectangular lattice, respectively; see Fig. S21 for separate X-ray patterns and detailed indexation in Table S2.</figcaption></figure>
diffuse scattering associated to partly molten chains. The 3D structure, which could be indistinctly of monoclinic, quadratic or orthorhombic nature, cannot be solved at this stage.

The diffraction patterns of **TPE-ThTP4** recorded at various temperatures unambiguously reveal the presence of a liquid crystalline phase, characterized by a large rectangular superlattice with lattice parameters *a* = 62.44 Å and *b* = 34.56 Å at 130°C (the lattice size is almost temperature invariant, Table S2). The S/WAXS patterns (Figs. 1b and S21) remain almost unchanged across the entire temperature range i.e., between 200 and 50°C, with peak positions and intensities being almost invariant, confirming the preservation of the mesophase characteristics. The entire set of small-angle reflections could be successfully indexed according to a two-dimensional lattice of rectangular symmetry (Table S2), whilst in the wide-angle region, a strong dispersion peak centred around 4.0-4.3 Å was observed, corresponding to undifferentiated alkyl chains in the molten state, *h*<sub>ch</sub>, and weak π-π interactions, *h*<sub>π</sub>, arising from the stacking of the triphenylene cores. Another small semi-diffuse reflection could also be seen, *h*', likely corresponding to some substantial intermolecular interactions (see below). The numerous, sharp small-angle reflections thus indicate the long-range two-dimensional expansion of the rectangular lattice, and confirm both the good segregation of the various molecular segments into regions of high electronic density (TP, Th, TPE) interspersed with a low-electronic-density aliphatic continuum (aliphatic chains) and their separation with well-defined aliphatic-aromatic interfaces. The atypical distribution of the reflection intensities is consistent with a low-symmetry alternating electronic density pattern (*p*2*gg* or *p*2*mg*, as deduced from the general conditions on the reflections: *hk*:h+k=2*n*+1, *h*0:*h*=2*n*, *ok*:k=2*n*), and is indicative of a large superlattice made of several columnar stacks.

The induction of the mesophase is very most likely driven
by the TP cores, which tend to stack to form distinct one-
dimensional columns while segregating from the aliphatic chains.
Furthermore, the shape incompatibility between TPE and TP and
the presence of aliphatic chains exclusively on the TP units, makes
mixed stacking between TP and TPE subunits highly unlikely. The
cross-sectional area of the rectangular lattice is compatible with
the accommodation of two complete molecular motifs within
the elementary cell. This is deduced from the calculated average
molecular thickness h<sub>mol</sub> = N<sub>mol</sub> × V<sub>mol</sub>/S, where V<sub>mol</sub> is the
molecular volume, and S is the lattice area directly deduced from
S/WAXS, S = a × b, and N<sub>mol</sub> is the number of molecules per
lattice (see Table S2, i.e., one molecule per columnar cross-section).
The molecular height varies between 5.65 and 5.75 Å quite close
to the value of h', which varies between 5.06 and 5.16 Å, over
a temperature range of nearly 200°C. From DFT calculations
(Tables S3-S4), the optimized conformation of **TPE-ThTP4** shows
that the planar triphenylene units are not in the same plane as
the benzene rings of TPE or the thiophene cycles, and make a
substantial tilt of ca. 45°, giving the tetrad an overall propeller-
shaped with out of plane TPs. Due to the presence of thiophene
bridges, **TPE-ThTP4** increases the radial size and conjugation
system of the molecule, resulting in a more flexible conformation
than for **TPE-TP4**. The most stable conformation for the cross-
shaped molecule is thus a fully stretched, extended cross-like

shape, with the peripheral triphenylene subunits separated from
the central TPE core and slightly tilted with respect to the lattice
plane. This specific conformation prevents any possibility for
intramolecular TPs stacking and rules out the stacking between
TP units from different tetrads within the same columns [18,35].
The value of the molecular thickness suggests that the peripheral
triphenylenes are tilted relative to the lattice plane, leading to
an oval columnar cross-section rather that purely circular, when
projected on the lattice. Based on these different facts, a plausible
supramolecular organization for the cross-shaped molecule within
the lattice can be proposed. The molecules in their fully expanded
configuration stack almost perfectly on top of each other while
being separated by the aliphatic continuum. The tetrads are
positioned on average at the nodes of the rectangular lattice, i.e.
at the centre and corners. The ethylene axis of the TPE-fragments
exhibits a slightly deviation from the lattice a-axis direction,
which affects the overall molecular orientation, allowing the
oligomer at the centre of the lattice to adopt either the same or
a different orientation relative to the corner molecule. This results
in two possible symmetry configurations: p2*gg* or p2*mg* (Fig. 2,
the difference lies in the respective orientation of the central
molecular motif with respect to those located at the corners), both
of planar symmetries which remain indistinguishable at this stage.

2.4 Gelation properties

Polycyclic aromatic hydrocarbon liquid crystals typically dissolve
in most organic solvents when heated, and subsequently self-
assemble into 1D supramolecular gel structures upon slow
cooling [36]. These structures can then be wound into fibres
and cross-linked, forming an infinite network that captures
solvent molecules, making them effective organic gelling agents.
Generally, the larger and more planar the π-conjugate scaffolds,
the stronger the gelation ability. Thus, the gelling behaviour of
the two star-shaped compounds was thoroughly examined by
heating various solutions of the compounds in a water bath
until complete dissolution and then by cooling slowly to room
temperature: gel formation was confirmed when the sample
stops flowing once the sealed glass vial was turned upside-
down (Fig. 3, Supporting Information Fig. S22). It was found
that **TPE-TP4** shows excellent solubility properties in both
polar and non-polar solvents, and logically does not exhibit
any gelation ability. In contrast, **TPE-ThTP4**, which possesses
a more extended molecular structure and a stronger degree of
conjugation, hence stronger π-π interactions than **TPE-TP4**, is
completely soluble in polar solvents like dichloromethane and
tetrahydrofuran, precipitates as a suspension in toluene, and is
only partially soluble in ethyl acetate (at concentrations less than
2.0 mg·mL⁻¹). However, it dissolves in non-polar solvents such as
*n*-hexane and cyclohexane when heated, and forms, when cooled,
a bright yellow opaque organic supramolecular gel at a critical
gel concentration of 4.0 mg·mL⁻¹ (Fig. S22). Furthermore, this
gelling process is thermally reversible, and the formed organic
gel is relatively stable. Even after several heating/cooling cycles,
no precipitation, crystallization, or other morphological changes
were observed. In order to gain further insights into the self-
assembled microstructures, scanning electron microscopy (SEM)
was used to examine the xerogels and suspension particles of **TPE-**
<figure><img src="image_6.png" /><figcaption>Fig. 2</figcaption></figure>

Schematic proposals for the supramolecular organization of **TPE-ThTP4** in the Col<sub>rec</sub> phase (2D lattice views) with *p2mg* or *p2gg* symmetry. Molecular representation: TPE core, green ovals; ThTP molecular fragment, purple ovals as the TPs are slightly tilted from the lattice plan; molten chains (not represented) in white continuum. The dotted circles represent the fluctuation domains of the peripheral thiophene-triphenylene arms.

**ThTP4** (Figs. 3 and S23). The results revealed that in *n*-hexane and cyclohexane, the xerogels exhibited a very extended three-dimensional porous network structure of intertwined flexible fibres with interconnected particles of the dispersed phase, trapping the solvent within. Upon solvent evaporation, the system loses its fluidity and becomes brittle and fragile. In contrast, the toluene xerogel showed an amorphous, plate-like sponge structure. These findings highlight the important synergistic effects of solvent polarity and π-π interaction on the formation of organic supramolecular gel.

## 2.5 Photophysical properties

The difference in the molecular structure of both tetraphenylethylene-triphenylene tetrad derivatives (presence of an additional thiophene functional group, extension of the π-conjugated system and increased flexibility) leads as expected to substantial differences in their electronic structure and corresponding photophysical properties, including light absorption and fluorescence emission. To explore these differences, UV-visible absorption and fluorescence emission spectra of solutions were recorded in four solvents (CYH, DCM, THF, DMF) for each compound along their emission in thin films. The results are summarized in Fig. 4 and Table 1 (see Supporting Information, Fig. S24). Both **TPE-TP4** and **TPE-ThTP4** exhibit strong and broad absorption peaks in the UV-vis region (Fig. 4a), with maximum absorption peaks centred around 276-284 nm and 264-266 nm, respectively. These signals are accompanied by smaller shoulders near 340 nm and 284 nm, which are attributed to the triphenylene and tetraphenylethylene fragments. The full band molar absorption coefficients (ε) exceed 10³ L·cm⁻¹·mol⁻¹, indicating strong absorption and a high probability of electronic transitions (Table 1). **TPE-ThTP4** also exhibits a third prominent absorption peak near 400 nm, which arises from the rigid electron-rich thiophene bridge that increases the conjugation system and the π-electrons delocalization over the larger molecular structure. This results in an increase in the HOMO energy level concomitantly with a decrease in the LUMO energy level (Figs. 5 and S24, Tables S7-S8). The energy gap ΔE consequently decreases, showing a significant intramolecular charge transfer (ICT) absorption

<figure><img src="image_7.png" /><figcaption>Fig. 3</figcaption></figure>

(a-c) SEM images of xerogels or suspension from **TPE-ThTP4** in different solvents. Inset shows the corresponding photographs of test tubes of organic-gel under natural light and 365 nm UV lamp (See also Figs. S22-S23).
<figure><img src="image_8.png" /><figcaption>Fig. 4</figcaption></figure>

UV-Vis absorption spectra (a); fluorescence emission spectra (b) and Lippert-Mataga curve (c) of **TPE-TP4** and **TPE-ThTP4** in different solvents (CYH, cyclohexane; DCM, dichloromethane; THF, DMF) and thin film; inserted image shows daylight/fluorescence photos of the cells in different solvents (See also Fig. S24 and Table S6).

band in the longer-wavelength region of the visible light. The absorption band corresponds to electronic transitions between energy levels with the following contributions, H-0→L+1(+50 %), H-1→L+0(+29 %), H-0→L+2(+18 %). As the solvent polarity increases, the maximum absorption peak of **TPE-TP4** shows a small red shift of 6-8 nm, indicating a π-π* transition. The

main orbital components and assignments are H-0→L+2(+54 %), H-0→L+1(+27 %), H-2→L+0(+27 %). This is consistent with the linear trend observed in the Lippert-Mataga curve (Fig. 4c, see supporting information for the formula and Table S6), which shows a steep slope (slope = 6757 cm⁻¹).

The fine structure of the absorption spectra is absent in the fluorescence emission spectra, which display only a single, broad, and intense emission signal (Fig. 4b). The emission maxima for **TPE-TP4** and **TPE-ThTP4** range between 461-521 nm and between 526-551 nm, respectively, and depend on the solvent polarity (Table 1). As the solvent polarity increases, from cyclohexane to DCM/THF/DMF, both **TPE-TP4** and **TPE-ThTP4** show red shifts of 52-60 nm and 16-25 nm, respectively. These variations are attributed to the increased rigidity and conjugation of the arms in the latter molecule, which promotes greater mobility of the π-electrons, resulting in a significant red shift in the fluorescence emission maximum. In non-polar solvents (e.g. cyclohexane), the rotation of the benzene rings in the tetraphenylenevinylene (TPE) core is partially restricted (restricted intramolecular rotation – RIR), reducing non-radiative transition pathways and enhancing fluorescence, predominantly. Meanwhile, the triphenylene (TP) units remain relatively isolated due to the low polarity of the solvent, avoiding aggregation. In contrast, in polar solvents, planar stacking of TP units through electrostatic interactions (such as dipole-dipole interactions) is promoted by enhanced π-π interactions, leading to the formation of exciplexes or excited-state quenching sites, enhancing non-radiative transition channels while reducing radiation decay channels. Furthermore, highly polar solvents may also stabilize distorted intramolecular charge-separated states (such as partial charge transfer between TPE and TP), leading also to a decrease in fluorescence emission efficiency. Thus, in highly polar solvents, the stabilization effects on the excited state are stronger than in the ground state, leading to a greater reduction in energy levels and a shift in fluorescence emission towards longer wavelengths, as evidenced by the positive slope of the Lippert-Mataga curve (Fig. 4c).

The absolute quantum yields of both compounds are highest in cyclohexane solution, at ca. 84 % and 30 %, for **TPE-TP4** and **TPE-ThTP4**, respectively, and the fluorescence of the solutions are correspondingly the brightest (Fig. 4c). Interestingly, when fluorescence was measured in thin films, no significant redshift in the maximum emission wavelength was observed compared to the various solutions. Instead, the most notable difference with the solutions was a change in the absolute quantum yields, which were approximately 92 % and 8 %, respectively (Table 1). This absence of redshift in the emission maximum may be attributed to the unique twisted conjugated structure of the propeller-type tetraphenylethylene-triphenylene tetrad molecules. This structure likely minimizes π-π aggregation interactions and reduced molecular orbital overlap, which typically contribute to an emission redshift. The variation in QY observed in the thin films can be explained by differences in the film morphology. Indeed, factors such as different degrees of crystallinity, inhomogeneity of film thickness and roughness, presence of domains with different sizes and orientations, can somehow influence the photophysical properties of the films, leading to significant increase/decrease in
<caption>Table 1</caption>

Summary of the UV-vis absorption[a] and fluorescence spectroscopic properties of TPE-TP4 and TPE-ThTP4 in various solutions[b] and thin films[c].

<table><thead><tr><th rowspan="2">Compound</th><th rowspan="2">Solvent</th><th colspan="5">Solution<sup>a,b</sup></th><th colspan="2">Film<sup>c</sup></th></tr><tr><th>λ<sub>abs</sub></th><th>ε</th><th>λ<sub>em</sub></th><th>QY</th><th>Δν</th><th>λ<sub>em</sub></th><th>QY</th></tr></thead><tbody><tr><td rowspan="6">TPE-TP4</td><td rowspan="2">CYH</td><td>276</td><td>2.58</td><td rowspan="2">461</td><td rowspan="2">84.5</td><td rowspan="2">14540</td><td rowspan="2">494</td><td rowspan="2">92.3</td></tr><tr><td>344</td><td>1.07</td></tr><tr><td rowspan="2">DCM</td><td>284</td><td>3.29</td><td rowspan="2">513</td><td rowspan="2">6.7</td><td rowspan="2">15718</td><td rowspan="2"></td><td rowspan="2"></td></tr><tr><td>338</td><td>1.23</td></tr><tr><td rowspan="2">THF</td><td>282</td><td>2.08</td><td rowspan="2">521</td><td rowspan="2">11.5</td><td rowspan="2">16267</td><td rowspan="2"></td><td rowspan="2"></td></tr><tr><td>340</td><td>0.74</td></tr><tr><td rowspan="2">DMF</td><td>282</td><td>3.63</td><td rowspan="2">519</td><td rowspan="2">12.0</td><td rowspan="2">16193</td><td rowspan="2"></td><td rowspan="2"></td></tr><tr><td>340</td><td>1.36</td></tr><tr><td rowspan="6">TPE-ThTP4</td><td rowspan="2">CYH</td><td>264</td><td>2.10</td><td rowspan="2">526</td><td rowspan="2">30.4</td><td rowspan="2">18867</td><td rowspan="2">551</td><td rowspan="2">8.2</td></tr><tr><td>308</td><td>1.27</td></tr><tr><td rowspan="2">DCM</td><td>404</td><td>1.55</td><td rowspan="2">549</td><td rowspan="2">6.2</td><td rowspan="2">19379</td><td rowspan="2"></td><td rowspan="2"></td></tr><tr><td>266</td><td>2.43</td></tr><tr><td rowspan="2">THF</td><td>284</td><td>2.05</td><td rowspan="2">551</td><td rowspan="2">8.5</td><td rowspan="2">19730</td><td rowspan="2"></td><td rowspan="2"></td></tr><tr><td>394</td><td>1.92</td></tr><tr><td rowspan="4">DMF</td><td>264</td><td>2.34</td><td rowspan="4">542</td><td rowspan="4">16.4</td><td rowspan="4">19144</td><td rowspan="4"></td><td rowspan="4"></td></tr><tr><td>284</td><td>1.94</td></tr><tr><td>396</td><td>1.86</td></tr><tr><td>266</td><td>0.63</td></tr><tr><td rowspan="3">TPE-ThTP4</td><td>284</td><td>0.53</td><td></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>400</td><td>0.47</td><td></td><td></td><td></td><td></td><td></td><td></td></tr></tbody></table>

[a] UV-vis absorption measured in different solvents with a concentration of $1 \times 10^{-5}$ mol L$^{-1}$ (λ in nm, absorption coefficient, ε, $\times 10^4$ L·mol$^{-1}$·cm$^{-1}$). [b] PL measured in various solvents with a concentration of $1 \times 10^{-5}$ mol·L$^{-1}$. Excitation wavelength: for TPE-TP4, 276 nm in CYH, 283 nm in DCM, 281 nm in THF, 282 nm in DMF, and for TPE-ThTP4, 361 nm in CYH/DCM/THF, 365 nm in DMF; Quantum yields (QY) in % were measured with solution concentration of $1 \times 10^{-5}$ mol·L$^{-1}$ excited at different wavelengths: 340 nm for TPE-TP4 and 365 nm for TPE-ThTP4. [c] The thin films were obtained by drop-casting dilute THF solution and evaporation of the solvent. Excitation wavelength: 310 nm for TPE-TP4 and 335 nm for TPE-ThTP4; Δν: Stokes shift in cm$^{-1}$.

quantum yields. Small- and wide-angle X-ray scattering (S/WAXS) experiments on the thin films also confirmed the difference in molecular aggregation states and stacking orders.

Geometric structures of the ground state were optimized in both the gas phase and THF solution by density functional theory (DFT) calculations to determine the minimal energy configuration (i.e., with the stable molecular conformations) and to analyse their frontier HOMO/LUMO distributions and energy levels, ensuring that all vibrational frequencies were positive. To simplify the calculations, the alkoxy chains were replaced by smaller methoxy groups (Fig. S25 and Tables S3-S10). Following this, time-dependent DFT (TD-DFT) calculations were then carried out to compute the most probable 30 electronic excitation absorption spectra, along with the corresponding electron-hole density maps, in THF solution at the same computational level (Figs. S26-S28). The results of these calculations (Fig. 5) show that the conformations of the compounds are nearly identical in both the gas phase and THF solution, with only a slight difference in energy gap (ΔE). The optimized conformations reveal that the planar triphenylene subunits do not lie in the same plane as the benzene rings of TPE or the thiophene cycles. A significant dihedral angle (approximately 45°) results in propeller-shaped structure with the triphenylene peripheral units out-of-plane. The thiophene bridges in TPE-ThTP4 increase both the radial size and conjugation system of the molecule, yielding in a more flexible conformation.

The increase π electron delocalization in the TPE-ThTP4 molecule raises the HOMO energy level and lowers the LUMO energy level, resulting in a smaller energy gap when compared to

TPE-TP4 (ΔE(TPE-ThTP4/THF) = 2.96 eV < ΔE(TPE-TP4/THF) = 3.51 eV), which is consistent with the optical measurements. However, it is worth further elaborating that the introduction of thiophene (Th) in the TPE-ThTP4 molecule expands the π-conjugated system, effectively reducing the energy gap (2.96 eV) and theoretically making it more excitable. However, it also results in longer residence time of electrons in low-energy gap systems (i.e., extended excited state lifetime), increasing the probability of non-radiative deactivation caused by solvent-molecule collisions (such as internal conversion (IC) and intersystem crossing (ISC)). In addition, the flexibility of thiophene as a bridge may also introduce more low-energy vibrational modes (i.e., enhanced vibrational relaxation), potentially allowing for rotation/vibration of part of the triphenylene or thiophene rings, thus providing more non-radiative decay pathways (such as promoting vibrational energy dissipation). Furthermore, the introduction of the thiophene conjugated bridge promotes the formation of the intramolecular charge transfer (ICT) state, thereby facilitating intersystem crossing (ISC), leading to a certain degree of fluorescence quenching. In summary, this results in a reduced quantum yield for TPE-ThTP4. Due to its rigid structure and local excitation advantage, TPE-TP4 more effectively suppresses non-radiative pathways, exhibiting high fluorescence efficiency. This comparison indicates that a reduction in energy gap is not always beneficial for fluorescence, and molecular design requires a balance between conjugation, rigidity, and excited-state dynamics.
<figure><img src="image_9.png" /><figcaption>Fig. 5</figcaption></figure>

Comparison of electronic properties (energy levels, frontier orbitals (HOMO and LUMO), and molecular electrostatic potentials (MEPs)) of **TPE-TP4** and **TPE-ThTP4** in vacuum and solution (THF). ("sol./exc." refers to the excited-state geometric structure and frontier orbitals of the molecule in THF solution.)

The distribution of the molecular electrostatic potential (MEP) is more balanced, which enhances the probability of π-π interactions between molecular fragments during aggregation (Fig. 5). This behaviour is supported by the self-assembly observed in liquid crystalline phases. The molecular orbital contour maps show intramolecular charge transfer (ICT) phenomena, with electron density primarily concentrated in the tetraphenylethylene nucleus and its adjacent conjugated units, irrespective of whether it is the HOMO or LUMO orbitals.

The electron-hole density maps of the two compounds in the liquid phase show charge separation occurring during the excited-state process, highlighting their potential as materials for organic optoelectronic devices.

## 2.6 Aggregation-induced emission

The tetrad compounds **TPE-TP4** and **TPE-ThTP4** are soluble in most organic solvents but insoluble in water (H₂O). To investigate their aggregation-induced effects, UV-visible absorption and fluorescence emission spectra were measured in several mixtures of THF/H₂O with varying volume fractions. The results are shown in Fig. 6 (Tables S11-S12). The UV-visible absorption spectra (Fig. 6a,b) show that as the proportion of water in the mixture increases, the π-π* transition absorption band of the conjugated molecular system broadens, while the overall ICT band undergoes a red shift. This shift is accompanied by a decrease in absorbance, suggesting that the molecule adopts a J-aggregation form through face-to-face interactions. When the water content reaches 60 % for **TPE-TP4** and 70 % for **TPE-ThTP4**, the redshift is more pronounced, indicating the strongest aggregation effect. Further increases in water content beyond these values, result

in no significant redshift of the ICT absorption band, suggesting a gradual decline in the aggregation effect. The fluorescence emission spectra (Fig. 6c,d) indicate that as the water content increases, the maximum emission peaks undergo a noticeable blue shift. This blue shift is particularly pronounced for **TPE-TP4** (Tables S11-S12, λ<sub>em</sub> varies from 522 to 472 nm for **TPE-TP4** and from 550 to 544 nm for **TPE-ThTP4**, with water fraction varying from 0 to 90 %). The blue shift correlates with the increase in aggregation, and the emission contribution becomes gradually dominated by the TPE component of the molecular system. Concurrently, the fluorescence intensity shows a marked increase, suggesting a strong interaction between the water content and the molecular properties of **TPE-TP4**, which may enhance its emission characteristics. At 90 % water content, the fluorescence intensity increases 8.70 times for **TPE-TP4** and 4.35 times for **TPE-ThTP4** compared to the initial solution (Fig. 6c,d). This enhancement occurs because, in a system without a strong electron donor-acceptor structure, the twisted, propeller-type tetraphenylethylene-triphenylene tetrad molecules pack tightly as the water content increases. This packing restricts intramolecular motions and inhibits non-radiative relaxation pathways, thus strengthening radiative decay channels and leading to greater fluorescence emission. The aggregation-induced fluorescence emission enhancement (AIEE) is therefore significant [15–17]. Notably, the fluorescence intensity of **TPE-TP4** increases almost linearly with increasing water content. In contrast, the fluorescence intensity of **TPE-ThTP4** increases suddenly to 3.78 times at 20 % water content, with subsequent increase in water content causing only small fluctuations between 3.74 and 4.35 times (Fig. 6f). This trend is consistent with the
<figure><img src="image_10.png" /><figcaption>Fig. 6</figcaption></figure>

UV-Vis absorption spectra (a/b), PL emission spectra (c/d), AIE fluorescence in solutions photos (e) and fluorescence intensity change map (f) of TPE-TP4 and TPE-ThTP4 in THF/H₂O with different water fraction.

pictures of solution-phase fluorescence (Fig. 6e). The difference can be attributed to the increased hydrophobicity resulting from thiophene bridging, which enlarges the molecular size and provides additional torsional space for the peripheral triphenylene discs. This increases the probability of π-π interactions and leads to some additional energy dissipation.

## 2.7 Applications as photodetector

Photodetectors are becoming essential components of modern information technology, and play an indispensable role in fields such as optical communication, surveillance, biosensing, and environmental monitoring [37]. They can be classified as ultraviolet (UV), visible, near-infrared (NIR), and mid/far-infrared detectors depending on their operating wavelength range. Due to their high sensitivity, ease of operation, and high integration, UV-visible photoconductive detectors are particularly interesting devices, and are being widely applied in UV communication, medical diagnostics, environmental pollution monitoring, and high-resolution imaging.

In this study, **TPE-TP4**, was selected as a high-purity material with excellent aggregation-induced emission activity, for its use as the absorption layer material for the photodetector. Combined with high electron-mobility graphene and broad-spectrum absorption (from UV to far-infrared), we fabricated a graphene/organic thin-film (**Gra/TPE-TP4**) composite photoconductive detector. The integration of graphene with the organic material **TPE-TP4** offers multiple advantages: on the one hand, graphene's high mobility and lack of dangling bonds effectively promote efficient separation and transport of photogenerated carriers; on the other hand, **TPE-TP4**, with its high light-absorption capability (in contrast to graphene's

intrinsic low light absorption efficiency) in specific wavelength ranges and flexible molecular design, provides a broad spectral response. By constructing a heterojunction with graphene, the device achieves superior optoelectronic performance and stability [38]. The design of this device leverages the synergistic effects of the two materials in light absorption, carrier separation, and interface engineering, offering a new approach to optimizing UV-visible photoconductive detectors.

For the device fabrication, graphene films were first transferred onto a SiO₂/Si substrate using a wet transfer technique (Fig. S29). Then, under high vacuum conditions ($2 \times 10^{-4}$ Pa), a 120 nm-thick Au electrode was deposited using a ZD-400 evaporation system. Subsequently, **TPE-TP4** thin film was deposited on the graphene layer through a mechanical mask, ultimately constructing the **Gra/TPE-TP4** composite photoconductive detector. When exposed to UV or visible light, the organic material **TPE-TP4** absorbs photons, generating electron-hole pairs. These pairs are efficiently separated through the device, leading to an increase in carrier concentration and a significant enhancement in conductivity, resulting in a strong photocurrent response.

UV-visible absorption spectra of the **TPE-TP4** thin film exhibit stable absorption in the 250-450 nm range (Fig. S30). Then, the **Gra/TPE-TP4** composite photoconductive detector was irradiated with a 405 nm commercial semiconductor laser and its optoelectronic response characteristics were measured using a source measurement system (Keithley 2636B Tektronix Inc, Beaverton, OR USA). Relevant information is collected in Fig. 7. Fig. 7a shows the I-V characteristics under dark conditions and 405 nm laser illumination, demonstrating a significant photocurrent response of the **Gra/TPE-TP4** detector under light exposure. When no light is incident on the device, the material exhibits high
<figure><img src="image_11.png" /><figcaption>Fig. 7</figcaption></figure>

(a) **Gra/TPE-TP4**: I-V characteristics under dark and illumination of 405 nm light, the insets display photographs and schematic diagram of the detector; (b) I-T curves under 405 nm; (c) photo-current curves at 405 nm under different incident optical power; (d) variation trend of photocurrent ($I_{ph}$) and correlation of responsivity ($R_i$) with optical power density at 405 nm.

resistance, and the device's dark current is low (Fig. 7a). When UV-visible light is incident, the semiconductor material absorbs the incoming UV-visible light, generating electron-hole pairs. The non-equilibrium carrier concentration increases, leading to additional conductivity, and the device current rapidly rises. The I-T cycling curve of the detector under 405 nm illumination (Fig. 7b) reveals the excellent photo response stability under fixed light power conditions, confirming the device's stable photodetection performance (see also Fig. S31). The photocurrent characteristics of the **Gra/TPE-TP4** detector (Fig. 7c) under 405 nm illumination at different incident light power densities (ranging from 71.95 mW·cm⁻² to 1.99 mW·cm⁻²) evidence a significant increase of the photocurrent with higher light power density, as expected, as more photons are absorbed by the material, generating more "photogenerated" carriers. The efficient separation and transport processes further convert these carriers into photocurrent, resulting in a positive correlation between photocurrent and light power density.

To quantitatively evaluate the optoelectronic performance of the **Gra/TPE-TP4** detector, key parameters such as photocurrent ($I_{ph}$) and responsivity ($R_i$) were calculated using the Eqs. (3)

and (4) shown in the Supporting Information. The changes in photocurrent and responsivity of the detector under different light power densities are summarized in Fig. 7d. The results show that the photocurrent increases rather linearly with light power density, while the responsivity significantly improves at low light power densities. At an incident light power density of 1.99 mW·cm⁻², the maximum responsivity at 405 nm reaches 8.35 A/W. These results demonstrate that the **Gra/TPE-TP4** composite photoconductive detector exhibits promising optoelectronic performance in the UV-visible range, highlighting the potential of this material and structure in high-performance photodetectors. This study also provides an effective strategy for designing low-cost, high-efficiency photodetectors.

### 3 Conclusion

Luminescent, propeller-like tetraphenylethylene-triphenylene conjugates were synthesized simply and efficiently through Suzuki-Miyaura coupling reaction between tetrabromotetraphenylethylene and triphenylene borate derivatives. These compounds exhibit ordered supramolecular self-assembly behaviour, good photoluminescence performance,
and photoconductive properties. The introduction of thiophene
bridges stabilizes the columnar liquid crystalline phase (TPE-TP4
is not mesomorphic) and expands the temperature range of the
liquid crystal, resulting in a Col<sub>rec</sub> mesophase width of over 300
°C for TPE-ThTP4. Both TPE-TP4 and TPE-ThTP4 exhibit
significant aggregation-induced luminescence enhancement
effects, with fluorescence intensities increased by 8.70 times
(TPE-TP4) and 4.35 times (TPE-ThTP4) compared to the initial
solutions at 90 % water content. Their absolute fluorescence
quantum yields in dilute solutions are as high as 84 % and 30 %,
respectively. DFT calculations indicate significant intramolecular
charge transfer phenomena and energy gap ΔE ≤ 3.51 eV.
This type of tetraphenylethylene-triphenylene LC tetrads have
potential application value in the field of organic thin film
devices due to its good self-organization, photoconductivity, and
processability. It provides a reference path for semiconductor
material designs that hope to expand conjugated structures to
increase carrier transport efficiency while maintaining excellent
aggregated luminescence properties.

**4 Experimental section**

4.1 Experimental details and characterization of the target
compounds

TPE-TP4: Under argon, 1,1,2,2-tetrakis(4-bromophenyl)ethene (64.8 mg, 0.10 mmol), **M5** (527.5 mg, 0.50 mmol), K₂CO₃ (276.4 mg, 2.00 mmol), Pd(PPh₃)₄ (34.7 mg, 0.03 mmol), were mixed and stirred in a H₂O/THF (3.0 mL/9.0 mL) solvent mixture. The mixture was heated to 70 °C for 48h with stirring. When cooled, the mixture was extracted with CH₂Cl₂, dried over MgSO₄, and the solvent removed under vacuum. The residue was purified by silica column chromatography with elution of CH₂Cl₂/petroleum ether 1.5:1 (v/v). Recrystallized from EtOAc-EtOH to yield a bright yellow solid **TPE-TP4** (274.9 mg, 85 %). ¹H NMR (CDCl₃, TMS, 600MHz) δ (ppm): 8.41 (d, *J* = 3.0 Hz, 1H), 7.93 (dd, *J* = 16.3, 2.6 Hz, 2H), 7.84 (d, *J* = 2.6 Hz, 3H), 7.62 (dd, *J* = 8.1, 3.2 Hz, 2H), 7.40 (dd, *J* = 8.1, 3.2 Hz, 2H), 4.25-4.20 (m, 6H), 4.17-4.14 (m, 2H), 4.12-4.11 (m, 2H), 1.96-1.91 (m, 6H), 1.82-1.74 (m, 4H), 1.59-1.38 (m, 22H), 1.29-1.28 (m, 4H), 1.21-1.20 (m, 4H), 0.95-0.91 (m, 9H), 0.86-0.84 (m, 3H), 0.80-0.77 (m, 3H). ¹³C NMR (CDCl₃, 151 MHz) δ (ppm): 155.06, 149.72, 149.25, 148.79, 142.72, 140.94, 136.79, 131.26, 130.40, 129.39, 129.19, 125.15, 124.77, 124.06, 123.21, 123.11, 123.05, 107.85, 107.53, 107.00, 106.79, 105.28, 69.81, 69.52, 69.40, 68.74, 31.67, 31.60, 31.36, 29.43, 29.41, 29.37, 29.30, 29.16, 25.84, 25.82, 25.79, 25.68, 22.64, 22.58, 14.04, 14.00, 13.97. HRMS (MALDI) m/z: [M]⁺ calcd for C₂₁₈H₃₀O₂₀, 3240.2525 (100.0 %), 3239.2492 (85.2 %), 3241.2559 (59.0 %), 3242.2592 (44.9 %), 3238.2458 (36.1 %); found, 3240.2521, 3239.2551, 3241.2540, 3242.2582, 3238.2602. Elemental analysis calcd for C₂₁₈H₃₀O₂₀ (3240.78): C 80.80, H 9.33; found, C 80.92, H 9.66.

TPE-ThTP4: Under argon, 1,1,2,2-tetrakis(4-
bromophenyl)ethene (69.1 mg, 0.11 mmol), **M7** (500.0 mg,
0.53 mmol), K₂CO₃ (294.9 mg, 2.13 mmol), Pd(PPh₃)₄ (49.3 mg,
0.04 mmol), were mixed and stirred in a H₂O/THF (3.0 mL/9.0 mL)
solvent mixture. The mixture was heated to 70 °C for 48h with
stirring. When cooled, the mixture was extracted with CH₂Cl₂,
dried over MgSO₄, and the solvent removed under vacuum.

The residue was purified by silica column chromatography with elution of CH₂Cl₂/petroleum ether 2:1 (v/v). Recrystallized from EtOAc-EtOH to yield a dark yellow solid **TPE-ThTP4** (205.6 mg, 54 %). ¹H NMR (CDCl₃, TMS, 600MHz) δ (ppm): 8.59 (s, 1H), 7.86 (s, 1H), 7.77 (s, 1H), 7.74 (s, 2H), 7.70 (s, 1H), 7.66 (d, *J* = 3.6 Hz, 1H), 7.56 (d, *J* = 8.0 Hz, 2H), 7.38 (d, *J* = 3.6 Hz, 1H), 7.23 (d, *J* = 8.0 Hz, 2H), 4.26-4.18 (m, 10H), 2.01-1.90 (m, 10H), 1.64-1.54 (m, 10H), 1.40-1.34 (m, 20H), 0.95-0.88 (m, 15H). ¹³C NMR (CDCl₃, 151 MHz) δ (ppm): 153.83, 149.68, 149.14, 148.74, 148.63, 143.38, 142.74, 140.32, 139.46, 132.95, 132.14, 129.10, 126.77, 124.89, 124.74, 123.71, 123.16, 123.01, 122.91, 122.67, 122.57, 122.40, 107.59, 107.30, 106.77, 106.52, 104.27, 69.72, 69.69, 69.39, 69.26, 68.82, 31.73, 31.71, 29.46, 29.45, 29.42, 29.37, 29.31, 26.09, 25.88, 25.86, 22.66, 14.05. HRMS (MALDI) m/z: [M]⁺ calcd for C₂₃₄H₃₀O₂₀S₄, 3568.2034 (100.0 %), 3569.2067 (83.6 %), 3567.2000 (79.4 %), 3570.2101 (36.5 %), 3566.1967 (31.4 %); found, 3568.2025, 3569.2040, 3567.2013, 3570.2081, 3566.2051. Elemental analysis calcd for C₂₃₄H₃₀O₂₀S₄ (3569.26): C 78.74, H 8.70, S 3.59; found, C 78.51, H 8.86, S 3.90.

**Declaration of competing interest**

We, the authors declare no conflict of interest

**Data availability**

Data will be made available on request.

CRediT authorship contribution statement

**Hang Lin:** Investigation, Formal analysis. **Ke-Xiao Zhao:**
Investigation, Formal analysis. **Bi-Qin Wang:** Funding
acquisition. **Ping Hu:** Funding acquisition. **Ke-Qing Zhao:**
Writing – review & editing, Writing – original draft, Supervision,
Methodology, Investigation, Funding acquisition, Formal
analysis, Data curation, Conceptualization. **Bertrand Donnio:**
Writing – review & editing, Writing – original draft, Methodology,
Investigation, Formal analysis, Data curation, Conceptualization.

**Acknowledgements**

This work was financially supported by the National Natural
Science Foundation of China (Contract No. 51773140, 51973143
and 21772135). BD thanks the CNRS and the University of
Strasbourg for support.

**Supplementary materials**

Supplementary material associated with this article can be found,
in the online version, at doi:10.1016/j.giant.2025.100362.

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