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[Hironobu Hayashi](https://orcid.org/0000-0002-7872-3052), Kizuku Yamamoto, [Madhuparna Chakraborty](https://orcid.org/0000-0002-5058-6973), [Junko Aimi](https://orcid.org/0000-0003-1339-0581), [Nobuyuki Ishida](https://orcid.org/0000-0003-0161-0583), [Naoki Aratani](https://orcid.org/0000-0002-3181-6526), [Hiroko Yamada](https://orcid.org/0000-0002-2138-5902)

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[Triptycene‐Based Organic Nanosheet Assemblies via Reversible Boronic Ester Formation: Alkyl Chain Length‐Dependent Formation and Aggregation](https://mdr.nims.go.jp/datasets/5e00a87c-1872-470f-a2ec-6ddf30e4ff90)

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Triptycene-Based Organic Nanosheet Assemblies viaReversible Boronic Ester Formation: Alkyl ChainLength-Dependent Formation and AggregationHironobu Hayashi1 | Kizuku Yamamoto2 | Madhuparna Chakraborty1 | Junko Aimi3 | Nobuyuki Ishida1 |Naoki Aratani2 | Hiroko Yamada41Center for Basic Research on Materials, National Institute for Materials Science (NIMS), Tsukuba, Ibaraki, Japan | 2Division of Materials Science, NaraInstitute of Science and Technology (NAIST), Ikoma, Nara, Japan | 3Research Center for Macromolecules and Biomaterials, National Institute forMaterials Science (NIMS), Tsukuba, Ibaraki, Japan | 4Institute for Chemical Research, Kyoto University, Uji, Kyoto, JapanCorrespondence: Hironobu Hayashi (HAYASHI.Hironobu@nims.go.jp) | Hiroko Yamada (hyamada@scl.kyoto-u.ac.jp)Received: 26 June 2026 | Revised: 26 August 2026 | Accepted: 10 October 2026Keywords: atomic force microscopy | boronic ester | nanosheet | reversible bond formation | triptyceneABSTRACTA bottom-up strategy for the preparation of triptycene-based organic nanosheet assemblies through reversible boronic ester for-mation is presented. The triptycene scaffold enables the orthogonal placement of alkyl substituents and boronic ester-formingsites, providing a molecular platform to examine how peripheral alkyl chains influence nanosheet formation and aggregation.Time-dependent microscopy observations revealed alkyl-chain-length-dependent assembly behavior. Hexyl-substituted precur-sors afforded sheet-like domains at an earlier stage, whereas methyl- and ethyl-substituted analogs showed slower formation ofless-defined nanosheet-like morphologies. These results indicate that longer alkyl chains are associated with earlier formation ofsheet-like domains and stronger aggregation; however, this alkyl-chain effect is described as an empirical trend rather than adefinitively established mechanism. Infrared spectroscopy supported boronic ester formation, and single-crystal structures ofpartial molecular analogs confirmed the orthogonal arrangement of the alkyl substituents relative to the framework-formingunits. Absorption measurements showed a slight red-shift for the nanosheet assemblies relative to the corresponding referencecompounds, consistent with modest extension of electronic communication within the boronic ester-linked framework. Thisstudy provides a case study showing that peripheral alkyl substituents can influence the formation and aggregation behaviorof triptycene-based organic nanosheet assemblies, offering useful insight into the development of dispersible 2D organic materials.1 | IntroductionPorous organic materials constructed from discrete molecularbuilding blocks have emerged as highly versatile platformsbecause their molecular structures, connectivity, and periodicitycan be tuned through rational monomer design [1–3]. In partic-ular, covalent organic frameworks (COFs), which exploitdynamic covalent bonds such as boronic esters and imine link-ages, have significantly expanded this field by enabling the con-struction of robust yet structurally diverse architectures [2–8].Among these materials, 2D COFs and related organic frame-works are particularly attractive because their anisotropic struc-tures and large interfacial areas provide opportunities forfunctional films, membranes, and substrate-supported materials[2–8]. However, practical implementation of COFs and relatedmaterials is often limited by their generally poor solubilityand dispersibility, which directly restricts solution processingand hampers their integration into device-oriented platforms.Therefore, the development of solution-processable or dispersible2D organic materials remains an important challenge [9–16].This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, providedthe original work is properly cited.© 2026 The Author(s). ChemPlusChem published by Wiley-VCH GmbH.ChemPlusChem, 2026; 91:e70276 1 of 8https://doi.org/10.1002/cplu.70276ChemPlusChemRESEARCH ARTICLEhttps://orcid.org/0000-0002-7872-3052https://orcid.org/0000-0002-5058-6973https://orcid.org/0000-0003-1339-0581https://orcid.org/0000-0003-0161-0583https://orcid.org/0000-0002-3181-6526https://orcid.org/0000-0002-2138-5902mailto:HAYASHI.Hironobu@nims.go.jpmailto:hyamada@scl.kyoto-u.ac.jphttp://creativecommons.org/licenses/by/4.0/https://doi.org/10.1002/cplu.70276https://doi.org/10.1002/cplu.70276http://crossmark.crossref.org/dialog/?doi=10.1002%2Fcplu.70276&domain=pdf&date_stamp=2026-10-27To address these limitations, several strategies have been explored,including mechanical and chemical exfoliation [17], ionic func-tionalization [11, 18], and the incorporation of bulky substituents[13, 19] to suppress interlayer interactions. For instance, ionic 2DCOF nanosheets can remain dispersed in aqueous media throughelectrostatic repulsion [18], while sterically demanding substitu-ents can facilitate exfoliation or suppress aggregation [19].Nevertheless, the direct solution-phase construction of organicnanosheet assemblies with controlled morphology remains insuf-ficiently developed, particularly with respect to how peripheralsubstituents affect nucleation, aggregation, and sheet-like assem-bly during reversible covalent formation.Previous studies have shown that peripheral substituents and side-chain interactions can influence the formation, crystallinity, andstacking structures of 2D COFs and related 2D polymers [20–23].For example, pendant alkyl or alkoxy chains have been reported toaffect stacking geometry, crystallinity, and framework formationin 2D COFs. Related studies have also shown that side-chain com-position can modulate the stacking order and material quality of2D polymers. These reports indicate that alkyl chains are notmerely solubilizing groups but can participate in the organizationof layered organic frameworks. Therefore, the effect of alkyl chainson COF and related framework formation has been explored inseveral systems. However, how peripheral alkyl substituents influ-ence the time-dependent formation and aggregation of triptycene-based dispersible nanosheet assemblies remains to be clarified.Herein, a synthetic approach to triptycene-based organic nano-sheet assemblies formed through reversible boronic ester bondsis presented (Figure 1) [24–26]. The triptycene scaffold allows theorthogonal introduction of alkyl substituents and network-forming diol units, providing a molecular platform in which sub-stituent effects can be examined independently from the boronicester-forming sites [27]. While previous studies on relatedtriptycene-based nanosheets mainly employed methyl-substitutedprecursors [27], the influence of longer peripheral alkyl chains onthe time-dependent formation and aggregation behavior of suchnanosheet assemblies has not been systematically examined. Inthis study, methyl-, ethyl-, and hexyl-substituted triptycene precur-sors were compared to examine how alkyl chain length affectsthe formation, aggregation behavior, and sheet-like morphologyof triptycene-based nanosheet assemblies. By combining time-resolved electron microscopy, atomic force microscopy (AFM),infrared (IR) spectroscopy, and crystallographic analysis of partialmolecular analogs, this work provides a case study showing thatperipheral alkyl substituents can influence the assembly behaviorof triptycene-based dispersible organic nanosheets.2 | Results and DiscussionHexahydroxylated triptycene derivatives bearing different alkylsubstituents as solubilizing groups (1a–c) were prepared accord-ing to established procedures (Scheme 1) [28, 29]. Briefly,demethylation of the corresponding hexamethoxy-triptycenederivatives using BBr3 afforded the triptycene-hexaol derivatives,which were used as key building blocks for nanosheet assembly.To gain structural insight into the local boronic ester motifs, par-tial molecular analogs were synthesized by condensing 1a and 1cwith phenylboronic acid in methanol, followed by solventremoval and thermal annealing at 90 °C under vacuum, affordingTripPh-Me and TripPh-Hx, respectively. In addition, Ref-L[30] was used as a linker analog to evaluate the structural char-acteristics of the phenylene boronic ester unit.Single crystals of these reference compounds were obtained byslow diffusion of acetonitrile into dichloromethane solutions(Figures 2 and S1). Single-crystal X-ray diffraction analysisrevealed that both TripPh-Me and TripPh-Hx adopt highlysymmetric structures, with dihedral angles of close to 120°between the triptycene core and the appended phenyl boronicester units. The phenyl boronic ester groups are oriented nearlyparallel to the phenyl rings of the triptycene core, while the alkylsubstituents are arranged approximately orthogonal to theboronic ester-forming units. Importantly, no substantial differen-ces in the local framework geometry were observed between themethyl- and hexyl-substituted analogs (Figures 2 and S1), indi-cating that variation of the alkyl chain length does not signifi-cantly perturb the triptycene-based boronic ester motif. Thesestructural features support a molecular design in which alkylsubstituents are introduced without directly interfering withthe network-forming sites. The planar structure of Ref-L(Figure 2), together with the 3D triptycene core, suggests thatthe resulting framework contains aromatic pore walls whilereducing close face-to-face stacking of the nanosheet assemblies.FIGURE 1 | Synthetic strategy for triptycene-based nanosheet formation.2 of 8 ChemPlusChem, 2026 21926506, 2026, 11, Downloaded from https://chemistry-europe.onlinelibrary.wiley.com/doi/10.1002/cplu.70276 by National Institute For, Wiley Online Library on [02/11/2026]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons LicenseTriptycene-based nanosheet assemblies were then preparedthrough reversible boronic esterification. As a representativeexample, the formation of NSPh-Hx from hexyl-substituted trip-tycene precursor (1c) and phenyl 1,4-diboronic acid was moni-tored over time. After 12 h, scanning transmission electronmicroscopy (STEM) already revealed micrometer-scale sheet-likefeatures, indicating that substantial growth and assembly hadoccurred by this time point rather than simple nucleation(Figure 3a). However, the morphology was still developing, asthe observed domains were less clearly defined than thoseobtained after longer reaction times. Extending the reaction to24 h afforded clearer sheet-like domains, as further supportedby AFM, which revealed multilayered nanosheet assemblies withmicrometer-scale lateral dimensions and thickness of ~4–6 nm insome regions (Figure 3b). This time-dependent observation sug-gested that the hexyl-substituted system undergoes relativelyrapid formation of connected sheet-like domains, followed byfurther growth and aggregation upon prolonged reaction. After72 h, scanning electron microscopy (SEM) showed extensiveaggregation into densely stacked assemblies. High-magnificationSTEM imaging was also performed on relatively thicker regionsto examine the structural features more closely (Figure S2). AFManalysis of a toluene-dispersed sample after drop-casting con-firmed the presence of multilayered nanosheet-like structures(Figure S3), suggesting that partial redispersion of the aggregatedmaterial is possible under appropriate conditions. The theoreticalmonolayer thickness was estimated from the molecular dimen-sions obtained from the single-crystal X-ray structure of themodel compound (Figure 2). When the peripheral hexyl chainsare considered, the expected monolayer thickness is ~1.5–2.0 nm.Although the actual conformation of the alkyl chains on micamay differ from the fully extended structure, the experimentallyobserved height of approximately 2 nm is reasonably consistentwith a monolayer or near-monolayer nanosheet. However, largerdomains often exhibited nonuniform heights, suggesting partialstacking, overlap, or aggregation rather than the formation ofuniformly stacked, large monolayer nanosheets. This tendencyis likely related to the aggregation-prone nature of the nanosheetassemblies. Therefore, these AFM features are described asstacked or assembled nanosheet-like domains with micrometer-scale lateral dimensions in some regions, rather than isolatedmonolayer nanosheets extending over several micrometers.Control experiments using either 1c or phenyl 1,4-diboronicacid alone under identical conditions produced only irregular,nonsheet-like aggregates (Figure 3c), highlighting the impor-tance of both triptycene-based precursor design and boronicester formation for the generation of sheet-like assemblies. Inaddition, increasing the precursor concentration led toenhanced random coupling and aggregation, presumably dueSCHEME 1 | Synthetic scheme for triptycene-based nanosheets with phenylene linkers and their reference compounds. Conditions: (a) phenyl 1,4-diboronic acid, mesitylene/1,4-dioxane (1:1, v/v), 85 °C; (b) phenyl boronic acid, 90 °C, 57% for TripPh-Me and 69% for TripPh-Hx.FIGURE 2 | Single-crystal X-ray structures of (a) TripPh-Hx and(c)Ref-L. Thermal ellipsoids represent 50% probability. Packing structureof (b) TripPh-Hx and (d) Ref-L. Hydrogen atoms are omitted for clarity.ChemPlusChem, 2026 3 of 8 21926506, 2026, 11, Downloaded from https://chemistry-europe.onlinelibrary.wiley.com/doi/10.1002/cplu.70276 by National Institute For, Wiley Online Library on [02/11/2026]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons Licenseto increased inter-nanosheet interactions. This observationemphasizes the importance of carefully controlled assemblyconditions.The nanosheets were isolated by centrifugation, and were furthercharacterized by IR spectroscopy (Figure 4). For NSPh-Hx, theO─H stretching bands at ~3200–3600 cm–1 were markedlyreduced relative to the skeletal vibration regions, while newbands appeared around 1270 and 1350 cm–1, assignable toC─O and B─O stretching vibrations, respectively [30]. A bandin the fingerprint region around ~650 cm–1 and the comparableIR features of the reference compound TripPh-Hx also supportthe formation of boronic ester linkages in NSPh-Hx. The resid-ual O─H signal observed for NSPh-Hx is likely attributable toterminal hydroxy groups at sheet edges or defect sites. Takentogether with the microscopy observations (Figure 3), these spec-troscopic results support the formation of boronic ester-linkednanosheet assemblies.After confirming boronic ester formation, the influence of alkylchain length on the nanosheet assembly process was examined,particularly with respect to aggregation behavior relevant to mor-phology development. This point is important because the presenttriptycene-based precursors differ from conventional planar COFbuilding blocks: the 3D triptycene core bears alkyl substituentsthat can modulate both dispersibility and intermolecular associa-tion. To evaluate the effect of alkyl chain length, nanosheet for-mation was compared using methyl- (1a), ethyl- (1b), andhexyl-substituted (1c) triptycene precursors, affording NSPh-Me, NSPh-Et, and NSPh-Hx, respectively. Time-course micros-copy revealed marked differences among the three systems(Figure 3). After 24 h, NSPh-Me and NSPh-Et showed incom-plete or ill-defined nanosheet-like domains, indicating that the for-mation of coherent sheet-like structures was still in progress. Incontrast, NSPh-Hx had already formed relatively clear sheet-likestructures. Notably, NSPh-Me exhibited a higher degree of struc-tural defects than NSPh-Et, suggesting that shorter alkylFIGURE 3 | (a) Time-resolved STEM characterization of NSPh-Hx (top), NSPh-Et (middle), and NSPh-Me (bottom) formation. SEM image isshown for NSPh-Hx after 72-h reaction. (b) AFM image and height profile of NSPh-Hx after 24-h reaction. (c) SEM image of aggregations obtainedonly with phenyl 1,4-diboronic acid (left) and 1c (right). (d) SEM image of aggregated NSPh-Me after 72-h reaction.4 of 8 ChemPlusChem, 2026 21926506, 2026, 11, Downloaded from https://chemistry-europe.onlinelibrary.wiley.com/doi/10.1002/cplu.70276 by National Institute For, Wiley Online Library on [02/11/2026]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons Licensesubstituents are associated with slower development of coherentsheet-like morphology. After 72 h, both NSPh-Me and NSPh-Eteventually afforded nanosheet-like structures; however, NSPh-Me still contained defective regions, whereas NSPh-Et displayedmore developed laminar features. In contrast, NSPh-Hx domainsunderwent more pronounced aggregation after prolonged reac-tion, indicating that the longer alkyl chains are associated withstronger aggregation of the nanosheet assemblies. Aggregate struc-tures were rarely observed in the NSPh-Me system, even afterextended reaction times (Figure 3d).In addition to morphological differences, macroscopic observa-tions of the reaction mixtures after 72 h also showed alkyl-chain-length-dependent behavior (Figure S4). The NSPh-Mereaction mixture turned yellow, implying partial oxidation ofthe triptycene-hexaol precursor 1a during the slower assemblyprocess (Figure S5) [31]. In contrast, the NSPh-Et and NSPh-Hxsystems retained their original appearance and produced white-gray precipitates, consistent with more efficient formation ofnanosheet assemblies. The recovered mass ratios of the precipi-tates, calculated from the recovered solid mass relative to the totalmass of the starting materials, were 0.61 for NSPh-Me, 0.67 forNSPh-Et, and 0.89 for NSPh-Hx, respectively (see SupportingInformation). These values indicate that the amount of aggregatedmaterial increases with alkyl chain length. Although these recov-ered mass ratios should not be interpreted as chemical yields, theyprovide a useful comparative measure of the extent of aggregatedassembly formation under the present conditions.These observations indicate that alkyl chain length influences theformation and aggregation behavior of triptycene-based nanosheetassemblies. The earlier appearance of sheet-like domains in thehexyl-substituted system can be empirically interpreted as beingrelated to a greater tendency toward intermolecular association dur-ing the assembly process [32, 33]. This view is consistent with thecrystal packing of TripPh-Hx (Figures 2 and S1), where the hexylchains are located in close proximity, as well as with the additionalAFM observations of TripPh-Hx and TripPh-Me (Figure S6).However, because no direct measurements or molecular-level sim-ulations of the assembly process were performed, van der Waalsinteractions or interdigitation cannot be assigned as the definitiveorigin of the faster nanosheet formation. Thus, the alkyl-chain effectis best described as an empirical trend: longer alkyl substituents cor-relate with earlier formation of sheet-like domains and strongeraggregation, whereas shorter substituents are associated with slowerand more defective nanosheet development.The optical absorption properties of the triptycene-based nano-sheet assemblies were examined and compared with those ofthe corresponding reference compounds, TripPh-Hx and Ref-L(Figure 5a). Because boronic ester bonds are reversible and sensi-tive to protic solvents and moisture, freshly prepared samples wereused for optical measurements in anhydrous solvents. Protic sol-vents such as methanol induced rapid decomposition into the cor-responding diboronic acid and triptycene precursors (Figure S7),and gradual hydrolysis was also observed in the presence of mois-ture. In dry 1,4-dioxane, TripPh-Hx and Ref-L exhibited absorp-tion maxima at 281 nm and 301 nm, respectively. In comparison,NSPh-Hx showed a slightly red-shifted absorption maximum at305 nm, consistent with modest extension of electronic communi-cation within the boronic ester-linked framework. The absorptionprofile of NSPh-Hx remained largely similar in dry 1,4-dioxane,tetrahydrofuran (THF), and N,N-dimethylformamide (DMF)(Figure 5b)—paralleling the solvent-independence observed forTripPh-Hx and Ref-L (Figures S8 and S9)—, whereas gradualFIGURE 4 | IR spectrum of (a) phenyl 1,4-diboronic acid, (b) 1c,(c) TripPh-Hx, and (d) NSPh-Hx.FIGURE 5 | (a) Normalized absorption spectra of NSPh-Hx and reference molecules (TripPh-Hx and Ref-L) in anhydrous 1,4-dioxane.(b) Normalized absorption spectra of NSPh-Hx in different anhydrous solvents.ChemPlusChem, 2026 5 of 8 21926506, 2026, 11, Downloaded from https://chemistry-europe.onlinelibrary.wiley.com/doi/10.1002/cplu.70276 by National Institute For, Wiley Online Library on [02/11/2026]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons Licensecolor changes in DMF indicate partial decomposition over time.Although the lower size limit for dispersible nanosheets wasnot fully established, these results suggest that the nanosheetassemblies can be dispersed in selected anhydrous organic sol-vents, although their stability is solvent dependent.Finally, structural diversification through variation of the dibor-onic acid linker was examined. Such linker variation is importantfor expanding the structural scope of triptycene-based nanosheetassemblies. The hexyl-substituted precursor 1c was reacted withseveral aromatic diboronic acids, including 4,4 0-biphenyldiboronicacid, p-terphenyl-4,4 00-diboronic acid, and pyrene-2,7-diboronicacid, affording NSBP-Hx, NSTP-Hx, and NSPy-Hx, respectively.These linkers range from linear oligophenylene units to apolycyclic aromatic structure, providing different rigidity andπ-conjugation lengths. AFM observations after drop-casting ontomica substrates showed thatNSBP-Hx, andNSPy-Hx formed rel-atively clear nanosheet-like morphologies (Figure 6). In contrast,theNSTP-Hx showed only partially sheet-like regions, and aggre-gated domains were frequently observed near these structures.Although these observations indicate that terphenyl linker canproduce sheet-like features in some regions, the morphology is lessuniform and less well-defined than those obtained with other link-ers, at least based on the present AFM observations. This behaviormay be related to the lower dispersibility or greater conformationalflexibility of the terphenyl-linked nanosheets, although this inter-pretation remains tentative. Therefore, the NSTP-Hx is describedas a partially sheet-like assembly rather than a well-defined nano-sheet. In all cases, height profile analysis indicated thicknessesranging from several nanometers to more than 10 nm, dependingon the linker and measured region, consistent with the formationof multilayered sheet-like assemblies. These results demonstratethat the present synthetic approach potentially accommodates dif-ferent aromatic diboronic acid linkers and provide access to struc-turally varied triptycene-based nanosheet assemblies.3 | ConclusionIn conclusion, triptycene-based organic nanosheet assemblieswere prepared through reversible boronic ester formationbetween hexahydroxylated triptycene precursors and aromaticdiboronic acids. The orthogonal arrangement of alkyl substitu-ents and boronic ester-forming sites, supported by crystallo-graphic analysis of partial molecular analogs, provides a usefulmolecular platform for examining substituent effects intriptycene-based nanosheet assemblies. Time-dependent micros-copy revealed that the alkyl chain length influences the forma-tion and aggregation behavior of these assemblies. Methyl-substituted precursors showed slower formation of less-definedand more defective sheet-like morphologies, whereas hexyl-substituted precursors produced sheet-like domains at an earlierstage, followed by aggregation into multilayered assemblies. Therecovered mass ratios of the aggregated assemblies also increasedwith alkyl chain length, providing a comparative indication ofalkyl-chain-length-dependent aggregation under the presentconditions. Absorption measurements showed a slight red-shiftrelative to reference compounds, consistent with modest exten-sion of electronic communication within the boronic ester-linkedframework. Furthermore, variation of the aromatic diboronicacid linkers afforded related sheet-like assemblies, althoughthe morphology depended on the linker structure and was lesswell-defined for the terphenyl-linked material. Overall, this workprovides a case study showing that peripheral alkyl substituentscan influence the formation, morphology, and aggregation behav-ior of triptycene-based organic nanosheet assemblies. These find-ings offer useful information for the development of dispersible 2Dorganic materials based on 3D molecular scaffolds.AcknowledgmentsThis work was supported by JST PRESTO (grant number JPMJPR21AC(HH)), JSPS KAKENHI (grant numbers JP24K01576 (HH), JP26K22862(HH), JP26K01575 (JA), JP26H00381 (HY), and JP25K01751 (HY)),Sumitomo Electric Group Corporate Social Responsibility Foundation(HH), the Hosokawa Powder Technology Foundation (HH), the InamoriFoundation (HH), the Kanamori Foundation (HH), the AdvancedResearch Infrastructure for Materials and Nanotechnology (ARIM) ofMEXT (grant numbers JPMXP1225NM5003, and JPMXP1225NM5140),and the NIMS Joint Research Hub Program. The authors would also liketo thank Chie Negoro and Taiga Naganawa (NIMS, Japan) for synthesis andAFM analysis.FIGURE 6 | AFM images and height profiles of (a) NSBP-Hx, (b) NSTP-Hx, and (c) NSPy-Hx. Diboronic acids for the corresponding nanosheetformation are also shown.6 of 8 ChemPlusChem, 2026 21926506, 2026, 11, Downloaded from https://chemistry-europe.onlinelibrary.wiley.com/doi/10.1002/cplu.70276 by National Institute For, Wiley Online Library on [02/11/2026]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons LicenseFundingThis study was supported by JST PRESTO (JPMJPR21AC), the Japan Societyfor the Promotion of Science (JP24K01576, JP26K22862, JP26K01575,JP26H00381, and JP25K01751), the Sumitomo Electric Group CorporateSocial Responsibility Foundation, the Hosokawa Powder TechnologyFoundation, the Inamori Foundation, the Kanamori Foundation, and theAdvanced Research Infrastructure for Materials and Nanotechnology(JPMXP1225NM5003 and JPMXP1225NM5140).Conflicts of InterestThe authors declare no conflicts of interest.Data Availability StatementThe data that supports the findings of this study are available in the sup-porting information of this article.References1. N. B. McKeown and P. M. 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Tsurumi, et al., “Fine-Tuning of theSequential Self-Assembly of Entangled Polyhedra by Exploiting the Side-Chain Effect,” Chemistry – An Asian Journal 20 (2025): e202401378,https://doi.org/10.1002/asia.202401378.Supporting InformationAdditional supporting information can be found online in the SupportingInformation section. Detailed synthetic protocols, single-crystal X-rayanalysis, optical properties, and details regarding the analytical methodsare provided in the Supporting Information. Deposition numbers 2559662(for TripPh-Hx), 2559664 (for TripPh-Me), and 2559665 (for Ref-L)contain the supplementary crystallographic data for this paper. Thesedata are provided free of charge by the joint Cambridge CrystallographicData Centre and Fachinformationszentrum Karlsruhe Access Structuresservice.8 of 8 ChemPlusChem, 2026 21926506, 2026, 11, Downloaded from https://chemistry-europe.onlinelibrary.wiley.com/doi/10.1002/cplu.70276 by National Institute For, Wiley Online Library on [02/11/2026]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons Licensehttps://doi.org/10.1021/acs.joc.5b01426https://doi.org/10.1021/cm070757qhttps://doi.org/10.1021/acs.joc.8b02706https://doi.org/10.1021/acs.joc.8b02706https://doi.org/10.1021/acsami.2c07313https://doi.org/10.1002/asia.202401378 Triptycene-Based Organic Nanosheet Assemblies via Reversible Boronic Ester Formation: Alkyl Chain Length-Dependent Formation and Aggregation 1. Introduction 2. Results and Discussion 3. Conclusion