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A novel fluorescein-bridged perylene bisimide (PBI) dimer for liquid crystal (LC) with geometrically symmetric structure was developed. The mesomorphic results indicated that the energetically stable and unstable conformers of fluorescein fragments could lead to the transformation of mesophases from a hexagonal columnar mesophase to an uncertain phase at 136.9 °C in heating, whilst a stable hexagonal columnar mesophase maintained between 175.6 °C and 58.6 °C in cooling. The selectively excited fluorescence characters in THF solution demonstrated that the fluorescence resonance energy transfer (FRET) effect between fluorescein fragments and PBI unites could provide a means to effectively impose strong fluorescence of the dimeric PBIs modified with suitable chromophore at the N-imide position, which alternatively serves as a platform for the further study of multi-functional PBI-based LCs.

The multiple BODIPY derivatives could exhibit higher fluorescence than mono-BODIPY derivatives but also might produce the stronger aggregation-induced quenching effect. It is important to investigate the relationship between fluorescence and numbers of BODIPY units. In this work, series of multiple BODIPY derivatives 2–5 with 1,3,5-triazine as core were designed and synthesized in high yields. A subtle balance between the fluorescence enhancement of multiple BODIPY units and fluorescence quenching based on H-aggregation of multiple BODIPY units was observed for these multiple BODIPY derivatives. Compound 3 bearing two BODIPY units with triazine as core presented the strongest fluorescence emission and highest fluorescence quantum yield. Compound 3 was successfully applied in viscosity measurement, exhibiting the linear relationship between fluorescence intensity (or steady-state emission anisotropy) and viscosity.

By the Schiff-base condensation of formacyl calix[4]crown(2) with raw chitosan, a novel calix[4]crown-grafted chitosan chelating polymer(3) was conveniently prepared in good yield. The structure of polymer 3 was confirmed by elemental analysis, infrared(IR) spectrometry and X-ray diffraction(XRD) analysis. The elemental analysis suggests that the grafting degree of calixcrown unit was 22% on the amino groups of chitosan. The morphological characteristic of polymer 3 was studied by scanning electron microscopy(SEM). Polymer 3 possessed loose porous and smooth morphology of surface. The dyes adsorption abilities of polymer 3 for a series of organic dyes[Orange I(OI), Neutral red(NR), Victoria blue B(VB) and Brilliant green(BG)] were studied by solid-liquid adsorption experiments. The adsorption percentages increased from 45%―60%(raw chitosan for dyes) to 75%―90%(polymer 3 for dyes). The highest adsorption percentage reached 89% for VB. The saturated adsorption capacities for OI, NR, VB and BG were as high as 622, 564, 854 and 781 mg/g, respectively. The adsorption abilities kept stable at 70%―90% in the scope of pH=5―9. The adsorption abilities for anionic dye(OI) decreased gradually with the increase of pH and the opposite trend was observed for cationic dyes(NR, BG, VB). The adsorption percentages were 70%―90% after five times’ cycles for adsorption.

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.

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 M n 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 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.

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.

The extraction ability of phenyl hydrazone derivatives of cone- and 1,3-alternate tetrathiacalix[4]arenes towards to some alkali, alkaline earth, transition and heavy metal ions has been investigated by picrate extraction method. The synthesized cone-tetrathiacalix[4]arene hydrazones show a high efficiency coupled with an excellent selectivity towards for Ag+ and Hg2+ ions. The stoichiometry of complexes and the extraction constants have been determined. The influence of calix[4]arene platform’s structure and the electron donor substituents in phenyl fragments on the extraction efficiency has been discussed.

The first example of triphenylene-modified chitosan 4 was prepared by reacting chitosan with triphenylene aldehyde derivative 3. Its structure and morphology was characterized by elemental analysis, 1H NMR, FTIR, XRD, SEM and AFM image. The triphenylene units in Tp-chitosan 4 appended on the skeleton of chitosan and possessed orderly layered structure. Adsorption experiments of Tp-chitosan 4 indicated that it possessed excellent adsorption capacities for both cationic and anionic dyes [Orange G sodium salt, Brilliant ponceau 5R, Victoria blue B (VB), Crystal violet (CV), Neutral red (NR) and Methylene blue]. The highest adsorption capacities for CV, VB and NR were 5.612, 5.353 and 5.375 mmol/g, respectively. Adsorption kinetics and isotherms analysis showed that the adsorption processes obeyed pseudo second-order model and the Langmuir isotherm equation. The adsorption processes were exothermic and spontaneous. The best pH values for adsorption were pH = 6–8.

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 M n 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.

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.

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 M n 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.

By formylation of calix[4]-1,3-aza-crown in hexamethylenetetramine/trifluoroacetic acid system, the first formylated calix[4]-aza-crown derivative 6 was synthesized in yield of 61%. Reacting compound 6 with salicyloyl hydrazine, 2,4-dinitrophenyl hydrazine, nicotinyl hydrazine or phenyl thiosemicarbazide afforded four novel calix[4]crown hydrazone derivatives 7a–d in yields of 70–90%. By condensating compound 6 with series of bifunctional reagents, the novel mono-bridged biscalix[4]-aza-crown hydrazone derivatives 8a–c were prepared in high yields. The extraction experiments showed that all new compounds were good receptors for metal cations, especially, for soft metal cations. The extraction results suggested that the hydrazone groups produced favorable influences for binding soft cations. The two calix[4]arene units in compounds 8a–c could bind metal cations concurrently.

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 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.

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.

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+.

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 calix[4]-1,3-aza-crown 2 with 1,6-diisocyanatohexane in “1+2” condensation mode, the first example dumbbell shaped biscalix[4]-1,3-aza-crown 3 was conveniently prepared in yield of 94%. The complexation properties of compound 3 were investigated by UV–vis spectra and 1H NMR experiments. The results showed that compound 3 has good complexation abilities for anions. Compound 3 binded monoacidic anions with 1:2 binding-stoichiometry and binded binary acidic anions with 1:1 binding-stoichiometry.

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%.

The X-ray structure of the alreadypublished p-tert-butylcalix[6]-1,4-2,5-bis(crown-4)1 is reported. Extraction of solid ammoniumpicrate in chloroform-d indicates thecation to be located outside of the calixcrown andforming a 1:2 (metal-ligand) complex.