•Novel perylene Schiff-base derivatives were synthesized.•They exhibited reversible trans/cis isomerization after UV-light irradiation.•The fluorescence-enhancing were firstly observed for trans-to-cis perylene.•The larger substituent leaded to the stronger fluorescence-enhancing.Three novel perylene Schiff-base derivatives 5a-5c were synthesized and characterized in yields of 80–85%. They exhibited reversible trans/cis isomerization after UV-light irradiation and heating. The fluorescence-enhancing effects were firstly observed for perylene trans-to-cis isomerization. The increasing steric hindrance based on the restricted intramolecular rotation of trans-to-cis isomerization was responsible for the fluorescence-enhancing effect. The larger substituent on Schiff-based groups leaded to stronger fluorescence intensity and high quantum yield.

The first near-infrared fluorescent and columnar liquid crystal based on Bodipy was achieved by modifying 3,5-alkenyl substituted Bodipy with two triphenylene units. Triphenylene-Bodipy-triphenylene triad with 3,5-alkenyl groups exhibited hexagonal columnar mesophase and near-infrared fluorescence at 650–800 nm with the quantum yield of 31%.

The first near-infrared fluorescent and columnar liquid crystal based on Bodipy was achieved by modifying 3,5-alkenyl substituted Bodipy with two triphenylene units. Triphenylene-Bodipy-triphenylene triad with 3,5-alkenyl groups exhibited hexagonal columnar mesophase and near-infrared fluorescence at 650–800 nm with the quantum yield of 31%.

Series of triads and pentads of perylene derivatives with two cholesterol units at the bay-position or four cholesterol units on both bay-position and imide position were designed and synthesized in yields of 55–65%. The influence of the different number and position of cholesterol substituents on mesomorphic properties and photophysical properties was studied. The results suggested that, in comparison with similar perylene derivatives with alkyl units at the imide position, the perylene liquid crystals with alkyl units at the bay-positions not only maintained excellent mesomorphic properties but also enhanced the fluorescence greatly. More cholesterol units resulted in a lower mesophase temperature, wider phase transfer temperature range, and higher fluorescence. A long spacer between perylene and cholesterol units led to more excellent mesomorphic properties and higher fluorescence.

Series of triads and pentads of perylene derivatives with two cholesterol units at the bay-position or four cholesterol units on both bay-position and imide position were designed and synthesized in yields of 55–65%. The influence of the different number and position of cholesterol substituents on mesomorphic properties and photophysical properties was studied. The results suggested that, in comparison with similar perylene derivatives with alkyl units at the imide position, the perylene liquid crystals with alkyl units at the bay-positions not only maintained excellent mesomorphic properties but also enhanced the fluorescence greatly. More cholesterol units resulted in a lower mesophase temperature, wider phase transfer temperature range, and higher fluorescence. A long spacer between perylene and cholesterol units led to more excellent mesomorphic properties and higher fluorescence.

The novel triphenylene derivatives with one, two or three diphenylacrylonitrile groups on the side chain were prepared in yields of 75–83%. The influence of the number of diphenylacrylonitrile groups on the mesophase and fluorescence properties were investigated. The triphenylene derivatives with one or two diphenylacrylonitrile groups exhibited not only the ordered hexagonal columnar mesophase but also good AIE fluorescence properties in both solution and solid state.

The novel triphenylene derivatives with one, two or three diphenylacrylonitrile groups on the side chain were prepared in yields of 75–83%. The influence of the number of diphenylacrylonitrile groups on the mesophase and fluorescence properties were investigated. The triphenylene derivatives with one or two diphenylacrylonitrile groups exhibited not only the ordered hexagonal columnar mesophase but also good AIE fluorescence properties in both solution and solid state.

Wendan decoction (WDD), a classic herb prescription in China, has been extensively proved to improve metabolic syndrome (Mets) in clinics. However, till now, its pharmacological mechanisms remained vague. In this study, a systematic approach that integrated GC-TOF/MS based metabolomics, multivariate statistical techniques (PCA and PLS-DA), KEGG pathway analysis and molecular docking simulation was established to explore the pathophysiological mechanisms of Mets and elucidate the molecular mechanisms of WDD against Mets rats. Compared to the control rat group, five significantly altered and impacted pathways (P < 0.05 and IV > 1) associated with thirty-nine significantly altered metabolites related to glycolysis, the TCA cycle, the urea cycle, amino acid and lipid metabolisms, gluconeogenesis and ketogenesis were identified as biomarkers of Mets. After two weeks of treatment, seventeen and fourteen significantly altered metabolites in the Mets model group tended to be restored to normal levels by WDD and metformin, respectively. Additionally, six significantly altered pathways were involved in treatment of Mets by WDD, while no significant pathway was found for metformin (P < 0.05). Finally, the molecular docking simulation revealed that seventy compounds in WDD competed with substrates to bind with four enzymes, which led to a reduction in the serum levels of significantly altered metabolites.

Herein, three phenylacrylonitrile-bridging triphenylene dimers were prepared by condensation and etherification procedure in moderate yields. They exhibited the ordered hexagonal columnar mesophase based on the strong columnar stacking-induced action of two triphenylene units. A subtle balance between fluorescence decrease and AIE effect existed upon adding H2O to the THF solution, resulting in high fluorescence for these novel AIE liquid crystals in both solid state and solution for the first time.

This study focuses on the construction of novel diphenylacrylonitrile-connected BODIPY dyes with high fluorescence in both solution and an aggregated state by combining DRET and FRET processes in a single donor–acceptor system. The first BODIPY derivatives with one, two, or three AIE-active diphenylacrylonitrile groups were designed and synthesized in moderate yields. Strong fluorescence emissions were observed in the THF solution under excitation at the absorption wavelength of non-emissive diphenylacrylonitrile chromophores, implying the existence of the DRET process between the dark diphenylacrylonitrile donor and the emissive BODIPY acceptor. In the THF/H2O solution, the fluorescence intensity of the novel BODIPY derivatives gradually increased under excitation at the absorption wavelength of diphenylacrylonitrile chromophores, suggesting a FRET process between diphenylacrylonitrile and BODIPY moieties. A greater number of diphenylacrylonitrile units led to higher energy-transfer efficiencies. The pseudo-Stokes shift for both DRET and FRET processes was as large as 190 nm.

•Three novel bis-Bodipy bridged with crown ether chain were prepared.•Compound 3b exhibited selective response for K+ with obvious ACQ effect.•The ACQ effect was controlled by K+ complexation of crown ether chain.•The crown ether chain was important for binding selective response.•The two Bodipy units were decisive factor for the fluorescence sensor.Three novel bis-Bodipy 3a–3c bridged with crown ether chain were prepared in yields of 70–78%. Their complexation absorption and fluorescent spectra for fourteen metal ions suggested that compound 3b exhibited the selective response for K+ with obvious ACQ effect. The association constant of compound 3b with K+ was 4.3 × 105 M−1 and 1:1 complex mode was deduced. The complexation mechanism of ACQ effect controlled by cation complexation of pseudo crown ether ring was confirmed by the fluorescent titrations, complexation FT-IR spectra, complexation 1H NMR spectra, complexation ESI-MS spectra and contrast experiment of similar mono-Bodipy derivative. The K+ was binded in the cavity of a pseudo crown ether ring, leading to the closed distance for two Bodipy units and then enhancing the ACQ effect obviously. Both the structure of the crown ether chain and two Bodipy units were decisive factors for the selective fluorescence sensor for K+.Download high-res image (129KB)Download full-size image

•Novel perylene liquid crystal with diphenylacrylonitrile groups was synthesized.•It showed the ordered hexagonal columnar mesophase.•Its fluorescence increased in THF/H2O mixtures when excited at 330 nm.•The pseudo Stokes shift was as large as 251 nm.•The AIE and FRET effect was firstly observed for perylene liquid crystal.A novel perylene liquid crystal with diphenylacrylonitrile groups on 1,7-bay positions was synthesized in high yield. This highly decorated perylene bisimide showed the ordered hexagonal columnar liquid crystalline behaviour between 124.9 and 189.5 °C. Upon excitation of 480 nm, an attenuation of fluorescent intensity was observed with the increase of water fraction in THF/H2O mixtures. However, the fluorescence intensity enhanced dramatically and attained a maximum value at water fraction of 40% in THF/H2O systems when excited at 330 nm. The fluorescence intensity increased by 10 times and the pseudo Stokes shift achieved 251 nm. These phenomena were well elucidated by the AIE and FRET effect, which were supported by the investigation of fluorescence quantum yield and fluorescence lifetime.Download high-res image (154KB)Download full-size image

•Three novel triphenylene tetramers were synthesized.•They possessed good columnar liquid crystal behaviors.•The first room-temperature mesophase were observed for triphenylene tetramers.•The mesomorphic properties could be tuned by the structures of spacers.Three novel triphenylene tetramers with triazole bridges, rigid aromatic Schiff-bases and hydrogen-bonding spacers were designed and synthesized in yield of 73–78%. Their structures were confirmed by IR, NMR and MS. Their mesomorphic properties were studied by polarizing optical microscopy, differential scanning calorimetry and X-ray diffraction. These novel triphenylene tetramers possessed the hexagonal columnar mesophase and exhibited excellent mesomorphic properties with melting points at 30–60 °C, which was first observed near room temperature for triphenylene tetramers. This study suggested that the mesomorphic properties of triphenylene oligomers could be tuned conveniently by the structures of spacers.

•Novel perylene liquid crystals with different bay-substituents were prepared.•They have good Colh mesophase and fluorescence properties.•They possess wide scopes of mesophase transfer temperatures.•The suitable bay-substituents were favorable for mesophase and fluorescence.A series of perylene liquid crystals with H, Br, phenyl and tert-butylphenyl on bay-positions were synthesized in yields of 50–70%. Their mesomorphic properties and photophysical properties were investigated. The perylene derivatives 6, 7 and 8 with Br, phenyl and tert-butylphenyl at bay-positions have the hexagonal columnar liquid crystalline phase and wider scopes of phase transfer temperatures in comparison with similar perylene liquid crystal 5 with no substituent on bay-position. Compounds 6, 7 and 8 showed stronger fluorescence intensities, larger Stokes shifts and higher quantum yields than that of compound 5. These results indicated that the suitable substituents on bay-positions of perylene liquid crystals were favorable for producing excellent mesomorphic properties and good fluorescence properties.

•Novel triphenylene–perylene–triphenylene triads were synthesized.•They possessed hexagonal columnar mesophase.•Strong Dexter electron transfer existed for these novel triads.•The larger π–π conjugated system enhanced the electron transfer property.Three novel triphenylene–perylene–triphenylene triads 5, 6, and 7 with short amido spacer and bay-substituents (H, Br, and tert-butylphenyl) were synthesized in yields of 40–70%. Their structural and conformational characterization had been achieved by FT-IR, NMR, and HR-MS. The studies of liquid crystalline behaviors suggested that triads 5, 6, and 7 possessed hexagonal columnar mesophase. The bay-substituents were favorable for decreasing the phase transitions temperature and enlarging the ranges of phase transfer temperatures. Their absorption spectra were similar to the absorption bands of analogues of triphenylene and perylene. Their fluorescence spectra exhibited strong Dexter electron transfer between triphenylene moiety and perylene moiety, resulting in drastic fluorescence quenching. The larger π–π conjugated system of perylene core enhanced the electron transfer property.

Two novel calix[4]arene–cholesterol derivatives 7a and 7b with Schiff-base bridges were synthesized in yields of 70–80%. Their structural and conformational characterization had been achieved by NMR, MS, and elemental analysis. Their mesomorphic behaviors were studied by polarizing optical microscopy, differential scanning calorimetry, and X-ray diffraction. They possess mesomorphic properties with the molecular arrangement of the calixarene bowlic column and Schiff-based cholesterol unit as ancillary lateral column. The complexes of 7a and 7b with AgClO4 showed no mesophase. These results suggested that the mesophase of compounds 7a and 7b could be tuned by the ion-complexation behavior.

•Novel triphenylene-Bodipy dyads were synthesized.•They exhibited good columnar liquid crystal behaviors.•They had excellent fluorescence properties with high quantum yields.•The alkyl increases the fluorescence but do not destroy mesophase.Four novel triphenylene-Bodipy dyads were synthesized in yields of 32–38% and characterized by MS, NMR, elemental analysis. They exhibit good columnar liquid crystal behaviors at room temperature. The alkyl substitution on the Bodipy unit does not cause the disruption of the mesophase. They possess excellent fluorescence properties with high quantum yields in solution and the weak fluorescence in film. The alkyl substitutions on the Bodipy unit increase the fluorescence intensity and the introduction of triphenylene units reduce the aggregation-caused quenching of orderly stacking of Bodipy units.

By using β-cyclodextrin aromatic aldehyde derivatives 5 and 6 as starting materials, the novel β-cyclodextrin-[60]fullerene conjugate 7 and bis-β-cyclodextrin-[60]fullerene conjugate 8 were designed and conveniently synthesized via the Huisgen [2+3] cycloaddition for the first time. The UV–Vis complexation experiments, fluorescence titration spectra and complexation ESI–MS spectrum suggested that they possessed excellent binding abilities for dyes with 1:1 host–guest complexes. The highest association constant of compound 8 for Orange I was as high as 6.97 × 105.

By reacting cyclodextrin-grafted thiacalix [4]arene derivative 9 containing three alkynyl groups with bis-azido compound 6, the first example of cyclodextrin-grafted thiacalix [4]arene netty polymer 10 was designed and prepared by the click chemistry in yield of 76 %. Its structure was confirmed by elemental analysis, 1H NMR spectrum, FTIR spectrum and XRD curve. The Mn of polymer 10 was 48,677, indicating average approximately 22 units of compound 9 in each polymer molecule. Its SEM image showed porous and loose morphology. Adsorption experiments of polymer 10 indicated that it possessed excellent adsorption capacities for both cationic and anionic dyes [Orange G sodium salt (OG), Brilliant ponceau 5R (BP), Victoria blue B (VB), Crystal violet (CV), Neutral red (NR) and Methylene blue (MB)]. The highest adsorption capacities for VB, CV, NR and MB were 5.821, 6.825, 6.135 and 5.381 mmol/g, respectively. Adsorption kinetics and isotherms analysis suggested that all the adsorption processes were exothermic and spontaneous. The adsorption processes obeyed pseudo second-order model and the Langmuir isotherm equation. The adsorption abilities of polymer 10 at pH values 3–11 were keep stable between 1.5–4 mmol/g. The adsorption abilities for anionic dyes decreased with the increase of pH values but opposite phenomena for cationic dyes. Polymer 10 showed good reused adsorption property after desorption in five times’ cycles.

Three novel gallic–perylene–gallic trimers 7, 8 and 9 were synthesized by reacting gallic amino derivatives 3, 4 or 6 with perylene tetracarboxylic anhydride in yields of 75%, 78% and 80%, respectively. Compounds 7 and 8 with soft bridging chains exhibit columnar mesophase at room temperature, but compound 9 with a rigid bridging chain exhibits no mesophase.

The first calix[4]arene-cholesterol liquid crystals were designed and synthesized in yields of 50–80%. Structural and conformational characterization of these new compounds had been achieved by NMR, MS, and elemental analysis. Their liquid crystalline behaviors were studied by polarizing optical microscopy, differential scanning calorimetry, and X-ray diffraction. All calix[4]arene derivatives with two or four cholesterol units show excellent mesomorphic properties of the columnar molecular arrangement of the calixarenes bowlic columns with cholesterol units as ancillary lateral columns. The long spacer and more cholesterol units were favorable for excellent mesophase.

Three novel gallic-calixarene derivatives 5, 6 and 7 were prepared in yields of 57–76%. Their structures and conformations were confirmed by element analyses, IR, ESI-MS and NMR spectra. Compounds 5 and 6 with stable cone conformation show liquid crystalline behaviours but compound 7 with no stable conformation exhibits no mesophase. These results indicated that the stable cone conformation plays a crucial role for mesomorphic property.

By reacting alkynylthiacalix[4]arenes with polyethylene glycol azido compounds, a series of novel thiacalix[4]arene 1,2,3-triazole-polyethylene glycol netty polymers were conveniently prepared in good yields. Their structures and morphologies were studied by 1H NMR, IR, and elemental analysis and SEM images. On average, approximately 28–31 thiacalixarene units exist in each polymeric molecule. These novel polymers possess excellent adsorption ability for both cationic and anionic dyes. The saturation adsorption capacity for Congo red reached 1.3–1.4 mmol/g. They exhibit high and stable adsorption ability in the scope of pH 5–9, and maintain good properties in five cycles.A series of novel thiacalix[4]arene 1,2,3-triazole-polyethylene glycol polymers were synthesized and they exhibited excellent adsorption capability for organic dyes.

Three novel calix[4]benzocrowns with π-conjugate azo groups on sidechains were designed and synthesized in ideal yields. Their structures and conformations were characterized by IR, 1H NMR, ESI–MS, elemental analysis. Their complexation abilities for dyes were investigated by liquid–liquid extraction experiments, complexation UV–Vis spectra and complexation ESI–MS spectra. The complexation experimental results suggested that they possessed excellent extraction abilities towards dyes. The highest extraction percentage of compound 3a for neutral red was 89.5 %. The complexation UV–Vis spectra of compounds 3a–c with four dyes indicated the 1:1 complexes between host and guest in DMSO solution. The association constant of compound 3b with OI was as high as 3.93 × 106 M−1. The complexation ESI–MS spectrum of compound 3c for Neutral red also supported the 1:1 complexes of host and guest. The complexation experiments showed these novel calix[4]arene receptors possess excellent complexation capabilities for dyes.

Click reaction of alkynylthiacalix[4]arene with ethyl 2-azidoacetate, followed by ammonolysis with hydrazine hydrate and Schiff-base condensation with benzaldehyde or salicyic aldehyde, afforded two novel thiacalix[4]arene derivatives containing multiple aromatic groups in yields of 86% and 90%. Their complexation properties for four organic dyes were investigated by liquid-liquid extraction experiments, complexation UV-Vis spectra and mass spectrum. The highest extraction percentage was 97% for Neutral red. The UV-Vis spectra and ESI-MS spectrum indicated the 1:1 complexes in DMSO solution. The association constants were as high as 1 ∼ 8×104 M−1. These complexation experiments showed that thiacalix[4]arene receptors possess excellent complexation capabilities for dyes.

By reacting β-cyclodextrin with 4-(prop-2-ynyloxy)benzaldehyde, the cyclodextrins (CDs) aromatic aldehyde derivative 6 was prepared in yield of 80 % via click chemistry of the Huisgen [2 + 3] cycloaddition reaction. Further Schiff-base condensation of compound 6 with salicylic hydrazide, nicotinohydrazide, or 2,4-dinitrophenylhydrazine, novel cyclodextrin derivatives with large conjugate acylhydrazone group 7a, 7b and 7c were conveniently obtained in yields of 75–85 %. Their structures were confirmed by elemental analysis, FT-IR, ESI–MS and NMR spectra. Their complexation properties for Orange I and Neutral red were studied by fluorescence titration spectroscopy and complexation MS spectrum. The results suggested that these novel CDs derivatives with large conjugate acylhydrazone group showed excellent complexation abilities for the tested dyes. The association constants were higher than 104 and the highest associations constant was 5.85 × 104 for host 7a with OI. The 1:1 complexes were formed in DMSO solution.

Two novel calix[4]benzocrown-[60]fullerene dyads were obtained by refluxing calix[4]benzocrown derivative containing formacyl group with sarcosine or glycine and C60 in toluene at reflux via 1,3-dipolar cycloaddition of azomethine ylides tied to C60 in the yields of 30 and 28 %, respectively. Their structures and conformations were characterized by UV–Vis, 1H NMR, ESI–MS, elemental analysis. Their complexation properties for four dyes were studied by liquid–liquid extraction experiments, complexation UV–Vis spectroscopy and complexation ESI–MS spectroscopy. The results of liquid–liquid extraction suggested that they exhibited excellent extraction abilities towards the four test dyes with the extraction percentages fluctuating in the scope of 75–90 %. The complexation UV–Vis spectra showed the 1:1 complexes between hosts and guests in DMSO solution. The association constants were as high as 5.40 × 104–1.05 × 106 M−1. The formation of 1:1 complex was further confirmed by the complexation ESI–MS spectrum of compound 4a for Neutral red in DMSO solution. These complexation experiments implied that the novel calix[4]benzocrown-[60]fullerene dyads possess excellent complexation abilities for organic dyes.

The novel calixarene-linked discotic triphenylene 5a and 5b were synthesized in good yields via click chemistry. Structural and conformational characterization of new compounds had been achieved by NMR, MS, and elemental analysis. Their liquid crystalline behaviors before and after complexation were studied by polarizing optical microscopy, differential scanning calorimetry, and X-ray diffraction. The neat compounds 5a and 5b showed mesophase but the complexes of 5a and 5b with metallic salts exhibited no liquid crystal behaviors.

Calixarene liquid crystals were important part among calixarene derivatives. The synthesis and mesomorphic properties of all kinds of calixarene liquid crystala have been discussed and reviewed. There are two methods to prepare calixarene liquid crystals. One way is to introduce the corresponding functional groups with long alkyl chains, which usually afford columnar liquid crystal with a rigid bowlic core. The organization of liquid crystals possesses interesting changes after the complexation of guests. Another way is to introduce triphenylene unit to obtain calixarenes bowlic column with triphenylene units as ancillary lateral columns or triphenylene column with calixarene units on ancillary side. Moreover, they showed interesting conversion between two kinds of liquid crystals before and after complexation with ions.

Based on the 1,3-dipolar cycloaddition of azomethine ylide generated in situ from aldehyde and sarcosine attached to C60, two novel benzo-15-crown-5/C60 dyads with a different linking chain in each were designed and synthesized in yields of 30% and 38%, respectively. It was found that their UV-Vis absorption spectra could be regulated hypsochromically by metal ions complexed. The long and soft linking chain was favorable for cooperate interaction of crown ether unit and C60 unit.

By introducing 1,2,3-triazole-ester groups on thiacalix[4]arene based on click chemistry and then ammonolysis with ethylenediamine, diethylenetriamine or triethylenetetramine, three novel 1,2,3-triazole-modified thiacalix[4]arene polymers were conveniently prepared in “4+2” condensation mode in ideal yields. The structures of polymers 4a–4c were confirmed by elemental analysis, FTIR and 1H NMR spectra. The surface morphologies of polymers 4a–4c were investigated by SEM micrographs. The Mn of novel polymers 4a–4c indicated approximately 18–20 calixarene units in each polymer molecule. The dye adsorption abilities of polymers 4a–4c for series of organic dyes (alizarin green, orange I, neutral red (NR), Congo red (CR), orange G (OG), crystal violet, Victoria blue B and methylene blue) were studied by solid–liquid adsorption experiments. The adsorption experimental results implied that they had excellent adsorption abilities for tested organic dyes. The highest adsorption percentage reached 97 % for OG. The best saturation adsorption capacities for NR and CR were as high as 1.282 and 1.407 mmol/g, respectively. These novel polymers possessed stable adsorption abilities in the scopes of pH 5–9 and had good reused properties after desorption. The adsorption mechanism proposed that not only dipole interaction, electrostatic interaction and hydrogen bonding interaction, but also the π–π stacking interaction plays important role in binding dyes.

Three new cyclodextrin-triphenylene derivatives 6, 7a and 7b were designed and synthesized by introducing a triphenylene unit into cyclodextrin based on click chemistry and further acylation of hydroxyl groups of the cyclodextrin unit. The column liquid crystal behaviour of cyclodextrin-triphenylene 7a was observed for the first time.

Three new cyclodextrin–triphenylene derivatives 6, 7a and 7b were designed and synthesized by introducing triphenylene unit on cyclodextrin based on click chemistry and further acylation of hydroxyl groups of cyclodextrin unit. The column liquid crystal behaviour of cyclodextrin–triphenylene 7a was observed for the first time by differential scanning calorimeter (DSC), polarizing optical microscopy (POM) and X-ray diffraction (XRD).

Using a click reaction between alkynylthiacalix[4]arene and ethyl 2-azidoacetate followed by an ammonolysis with ethanolamine, leucinol and hydrazine hydrate, respectively, three novel thiacalix[4]arene derivatives 4, 5 and 6 with triazolyl and hydrogen bonding groups (NH and OH) were synthesized in high yields. They exhibited excellent extraction capability for six anionic and cationic dyes. The flexible cavity, π-triazole rings and hydrogen bonding groups all play crucial roles in dye complexation.Several novel thiacalix[4]arene derivatives with triazolyl and hydrogen bonding groups 4, 5 and 6 were synthesized and exhibited excellent extraction capability for six anionic and cationic dyes.

Two novel symmetrical triads of triphenylene-calix[4]arene-triphenylenes 6a and 6b bridged by hydrazone spacers were synthesized in high yields. They possessed interesting ion complexation-induced mesomorphic conversion between two columnar phases. The neat compounds 6a and 6b showed mesophase with calixarene’s bowlic column as cores. The Ag+-complexes of 6a and 6b exhibited mesophase with triphenylene column as cores.

Two novel deep-cavity calix[4]arenes 3 and 4 with large s-triazine π-conjugate systems were designed and synthesized in high yields by reacting calix[4]arene with mono phenyl-substituted cyanuric chloride or further substitution with aniline. The liquid–liquid extraction experiment showed that they possessed excellent extraction abilities towards one cationic and three anionic dyes (Orange I, methylene blue, neutral red, brilliant green). The highest extraction percentage of compound 4 was 88.8 % for brilliant green. The complexation UV–Vis spectra of compounds 3 and 4 with four dyes indicated the existences of complexation action between hosts and guests with 1:1 ratio of complexation in DMSO solution. The association constants suggested that the larger π-conjugate system of compound 4 possessed the stronger complexation abilities than that of compound 3. The association constant of compound 4 with BG was as high as 8.1 × 106 M−1.

Two novel symmetrical triads of triphenylene-calix[4]arene-triphenylene bridged by aromatic amido or hydrazone spacers were synthesized with stepwise procedures in yields of 67% and 68%, respectively. They exhibited interesting mesomorphic behavior of triphenylene column with calix[4]arene units on ancillary lateral sides.

By reacting calix[4]arene 1,3-bi-hydrazide derivative (2) with formacylferrocene in “1 + 2” condensation mode, novel calix[4]arene derivative bearing two conjugated ferrocene groups (3) was obtained in yield of 88%. By reacting 1,3-bi-substituted [2-(p-formylphenyloxy)ethyloxy]-p-tert-butylcalix[4]arene (5) with 1,1′-diacetylferrocene hydrazone (4) in “1 + 1” condensation mode, novel calix[4]arene derivative with 1,3-substituted large conjugated ferrocene bridge (6) was synthesized in yield of 83%. The structures and conformations of new compounds were confirmed by elemental analyses, IR spectra, ESI-MS, 1H NMR, etc. The electrochemical cyclic voltammetry experiments revealed that compounds 3 and 6 possessed excellent reversible electrochemical properties. The 1H NMR titration study showed that compound 6 possessed excellent complexation abilities for NaH2PO4 and glycine in 1:1 host–guest complex with the association constants of 3,850 and 2,460 M−1, respectively.

The first examples of calixarene ionic liquids 3 and 6 with 3D-shaped cavities were obtained in high yields by reacting calix[4]arene or thiacalix[4]arene with 1,6-dibromohexane and then refluxing in 1-methylimidazole. The experiments of phase transfer catalysis in water suggested that they possessed excellent catalytic properties of aromatic nucleophilic substitution reaction and benzyl nucleophilic substitution. The optimized yields of product in catalytic reaction were as high as approximate 97% under mild reaction conditions. The cavities of calixarene skeleton played the crucial roles in catalysis and the stable cone conformation was favorable for catalysis.

By introducing four ester groups on p-tert-butylcalix[6]-1,4-crown-4 and then ammonolysis with ethanolamine, p-tert-butylcalix[6]-1,4-crown-4 amido derivative with four terminal hydroxyl groups (4) was obtained in good yield. Further by reacting compound 4 with 1,1,1-tris(tosylatemethyl)propane (6) in NaH/THF system, the novel netty calix[6]-1,4-crown-based polymer 7 was prepared in “4+3” condensation mode. The structure of polymer 7 was confirmed by elemental analysis, IR and 1H NMR spectra. The loose pores and cross-linked netty architecture were observed for polymer 7 in its SEM images. The Mn of polymer 7 was 39,816 which indicated an average of approximately 23 calixarene units in each polymer molecule. Polymer 7 exhibited outstanding adsorption abilities for series of aniline derivatives (aniline, o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, o-nitroaniline, m-nitroaniline and p-nitroaniline). The adsorption percentages for these aniline derivatives were above 90 %. The saturation adsorption capacities for aniline and p-nitroaniline were as high as 2.30 and 2.22 mmol/g, respectively. The adsorption abilities of polymer 7 kept stable at pH 6–10 and it could be re-used after desorption of 10 % HCl. The high adsorption abilities of polymer 7 for aniline derivatives were not just because of π–π stack action of the phenyl groups and the hydrogen bond action, but also due to the stable conformation of calix[6]arene skeleton and big cavity, which were favorable for adsorption of aniline derivatives.

Four novel calix[4]arene hydrazone-based receptors 3a–d were prepared in yields of 69–87% by condensating formylated calix[4]arene ester (2) with salicylyl hydrazine, 2,4-dinitrophenyl hydrazine, nicotinyl hydrazine or phenyl thiosemicarhazide, respectively. New compounds were characterized through elemental analysis, IR, ESI–MS, 1H NMR studies. Compounds 3a–d containing two binding sites had the complexation abilities for hard and soft cations concurrently. The noncompetitive extracting experiments showed compounds 3a–d were excellent receptors for hard and soft metal cations. The competitive extracting experiments exhibited the cooperative complexation in binding hard and soft metal cations and compound 3a possessed outstanding selectivity for Na+ and Hg2+. The IR spectra of compound 3a before and after complexation revealed that the soft metal cation was binded in the cavity composed of hydrazone groups and azo groups at the upper rims of calix[4]arene units and hard metal cations was binded in cavity composed of ester groups and phenolic hydroxyl groups at the lower rims of calix[4]arene units.

By reacting thiacalix[4]arene with N,N′-bis(2-chloracetamide)ethylene in Na2CO3/toluene or K2CO3/toluene system, novel thiacalix[4]-1,3-aza-crown 3 and mono-bridged bisthiacalix[4]-aza-crown 4 were selectively synthesized in “1 + 1” cyclocondensation or “1 + 2” condensation in moderate yields. Novel bis-bridged bisthiacalix[4]-1,3-aza-crown 5 was prepared by further condensating compound 4 with N,N′-bis(2-chloracetamide)ethylene in Na2CO3/toluene. The non-competitive and competitive liquid–liquid extraction experiments showed that new hosts possessed good extraction capabilities for soft cations. Hosts 3 and 5 showed good extraction selectivities for Ni2+ and Ag+, respectively. The 1H NMR titration experiment showed 1:1 stoichiometry of the complex between host 5 and Ag+.

A novel redox calix[4]arene derivative with 1,3-substituted large conjugated ferrocene bridge was designed and synthesized in high yield. Its structure was characterized by element analysis, IR, ESI-MS, NMR spectrum, etc. The primary study of cyclic voltammetry showed it possessed excellent reversible electrochemistry response property.

By reacting calix[4]-1,3-aza-crown 2 with 1,4-phenyl diisothiocyanate in “1 + 2” condensation mode, the novel dumbbell shaped biscalix[4]-1,3-aza-crown 3 with rigid thiourea-bridge was conveniently prepared in yield of 85%. Its structure and conformation were characterized by elemental analyses, ESI-MS, 1H NMR and 1H–1H COSY techniques. The complexation properties of compound 3 were investigated by liquid–liquid extraction experiments and 1H NMR titration experiments. The results showed that compound 3 has excellent complexation abilities for soft cations and outstanding extraction selectivity for Ag+. The Ag+/Na+ and Ag+/Hg2+ extraction percentage of host 7 were as high as 43.2 and 16.9, respectively. 1H NMR titration experiments revealed the 1:2 stoichiometry of receptor 3-Ag+ complex was formed.

By reacting thiacalix[4]arene with p-tosyloxyethoxylbenzaldehyde 1, 3-bis(benzaldehyde-4-oxyethyloxy)-p-tert-butylthiacalix[4]arene (2) were prepared in yield of 65%. Refluxing compound 2 with aniline, salicylic hydrazide, nicotinic hydrazide and isonicotinic hydrazide, novel ringopening 1,3-bis-arylformyl-hydrazone substituted thiacalix[4]arene derivatives (3a–3d) were obtained in yields of 77–89%. Refluxing compound 2 with o-phenylendiamine, oxalyl dihydrazide, malonic dihydrazide and adipic dihydrazide in “1 + 1” intermolecular condensation mode under diluted condition, novel 1,3-bis-acyl hydrazone-bridged calix[4]arene derivatives (4a–4d) were prepared in good yields. Moreover, by condensating compound 2 with 1,3-bis(hydrazinocarbonyl-methoxy)-p-tert-butylcalix[4]arene (5), the first example of hydrazone-bridged biscalixarene (6) with calix[4]arene and thiacalix[4]arene subunits was facilely synthesized in yield of 90%. The noncompetitive and competitive extracting experiments showed that these novel hosts were good receptors for both metal cations and α-amino acids. Compounds 3a–3d and 4a–4d showed similar binding properties with high extraction percentage but low extracting selectivities. Biscalixarene 6 exhibited not only high extracting abilities but also good extracting selectivities.

The novel thiacalix[4]-1,3-2,4-aza-biscrown 3 in 1,3-alternate conformation, was facilely prepared by “1 + 2” cyclocondensation of p-tert-butylthiacalix[4]arene tetrahydrazide derivative 2 with o-phthalaldehyde in yield of 78%. The liquid–liquid extraction experiment showed that compound 3 was excellent receptor for zwitterionic α-amino acids and soft cations Ag+ and Hg2+. The extraction percentage of methionine was as high as 78%.

This study focuses on the construction of novel diphenylacrylonitrile-connected BODIPY dyes with high fluorescence in both solution and an aggregated state by combining DRET and FRET processes in a single donor–acceptor system. The first BODIPY derivatives with one, two, or three AIE-active diphenylacrylonitrile groups were designed and synthesized in moderate yields. Strong fluorescence emissions were observed in the THF solution under excitation at the absorption wavelength of non-emissive diphenylacrylonitrile chromophores, implying the existence of the DRET process between the dark diphenylacrylonitrile donor and the emissive BODIPY acceptor. In the THF/H2O solution, the fluorescence intensity of the novel BODIPY derivatives gradually increased under excitation at the absorption wavelength of diphenylacrylonitrile chromophores, suggesting a FRET process between diphenylacrylonitrile and BODIPY moieties. A greater number of diphenylacrylonitrile units led to higher energy-transfer efficiencies. The pseudo-Stokes shift for both DRET and FRET processes was as large as 190 nm.