Two low molecular weight gelators containing 4-ethynyl-1,8-naphthalimide groups with large conjugated structure via different length of alkyl chains were synthesized and fully characterized. The gelation properties, structural character, and fluorescence of the gels were investigated via methods of scanning electron microscopy, X-ray diffraction, and spectral studies. The gelators have high fluorescence quantum yields in both solution and solid state. Interestingly, the wavelength of the fluorescent emission in the reversible sol–gel transition process of the gels has a large red-shift of 80 nm in DMF, which is extremely sparse for 1,8-naphthalimide derivatives in the literature. The intermolecular π–π stacking between naphthalimide is suggested to be the main driving force for the gel formation and fluorescent variation by means of temperature-dependent 1H NMR study and theoretical calculation.

Large Red-Shifted Fluorescent Emission via Intermolecular π–π Stacking in 4-Ethynyl-1,8-naphthalimide-Based Supramolecular Assemblies

pH-sensitive peptide hydrogel for glucose-responsive insulin delivery.

Herein, we report a new strategy to remove toxic Cr(VI) ion from aqueous solution using metal–organic hybrid gel as sorbent. The gel could be easily synthesized from the commercially available organic ligand 2-mercaptobenzimidazole (2-MBIm) and copper(II) chloride in alcoholic medium. The synthesis involves one-electron reduction of Cu(II) to Cu(I) by 2-MBIm, and then gel formation is triggered through Cu(I)–ligand coordination and extensive hydrogen-bonding interactions involving the “–NH” protons (of 2-MBIm ligand), solvent molecules, and chloride ions. The gel shows entangled network morphology. Different microanalytical techniques (FTIR, powder XRD, FESEM, TEM, rheology etc.) have been employed for complete characterizations of the gel sample. Both Cu(I) (in situ formed) and Cl– ions trigger the gel formation as demonstrated from systematic chemical analyses. The gel also exhibits its stimuli-responsive behavior toward different interfering chemical parameters (pH, selective metal ions and anions, sel...

Redox-Responsive Copper(I) Metallogel: A Metal–Organic Hybrid Sorbent for Reductive Removal of Chromium(VI) from Aqueous Solution

A novel multifunctional gelator (1) based on an azobenzene derivative was designed and characterized. This compound could gelate some solvents including hexane, petroleum ether, DMSO, acetonitrile and ethanol through a heating–cooling procedure. The self-assembly process in different solvents was studied by means of UV-vis absorption and Fourier transform infrared (FTIR) spectra, field emission scanning electron microscopy (FESEM), rheological measurements, X-ray powder diffraction and water contact angle experiments. Interestingly, compound 1 had a high-contrast colorimetric detection ability towards Hg2+, Cu2+, Fe3+ and volatile acids and further organic amine gases in solution through its color change. At the same time, organogel 1 in acetonitrile also exhibited detection performance through a color or gel state change. In the response process, the self-assembly structures were changed from a nanofiber into a microsphere under induction by analytes. More significantly, film 1 could continuously detect volatile acids and organic amine gases. The number of cycles of film 1 for the detection of volatile acids and organic amine gases was at least seven times. The limit of detection (LOD) of film 1 towards TFA was calculated to be 0.0848 ppb. The sensing mechanisms were studied using 1HNMR, FESEM, UV-vis absorption spectra and HRMS. The intramolecular cyclization occurred on molecule 1 and a H2S molecule was lost during the detection process of Hg2+. It was proposed that the –NN– bonding could be coordinated by Fe3+ and Cu2+ and this further induced the absorption spectra and color change. For a volatile acid, it was possible that the volatile acid was combined with the N,N-dimethyl amine group of molecule 1. This research opens up a novel pathway to the fabrication of supramolecular self-assembly gels to detect polymetallic ions and trace volatile acids in the environment.

Multifunctional supramolecular self-assembly system for colorimetric detection of Hg2+, Fe3+, Cu2+ and continuous sensing of volatile acids and organic amine gases.

The transformation of recognition signals into regulating macroscopic behaviors of biological entities (e.g., biomolecules and cells) is an extraordinarily challenging task in engineering interfacial properties of artificial materials. Recently, there has been extensive research for dynamic biointerfaces driven by biomimetic techniques. Weak interactions and chirality are two crucial routes that nature uses to achieve its functions, including protein folding, the DNA double helix, phospholipid membranes, photosystems, and shell and tooth growths. Learning from nature inspires us to design dynamic biointerfaces, which usually take advantage of highly selective weak interactions (e.g., synergetic chiral H-bonding interactions) to tailor their molecular assemblies on external stimuli. Biomolecules can induce the conformational transitions of dynamic biointerfaces, then drive a switching of surface characteristics (topographic structure, wettability, etc.), and eventually achieve macroscopic functions. The emerging progresses of dynamic biointerfaces are reviewed and its role from molecular recognitions to biological functions highlighted. Finally, a discussion is presented of the integration of dynamic biointerfaces with the basic biochemical processes, possibly solving the big challenges in life science.

Dynamic biointerfaces: from recognition to function.

A new phenylboronic acid based gelator was developed to prepare low-molecular-weight organogel (LMOG), which could interact with several solvents to assemble into a three-dimensional nanofiber network. 1H NMR spectroscopy study suggests that the driving force for the gelation includes hydrogen bonding and π–π stacking. Evaluated by UV-spectroscopy, the gel showed a prompt initial response to glucose at low concentration of 0.012 mmol/mL, which is a critical concentration of venous plasma glucose for diabetes. Significantly, this organogel exhibits excellent sensitivity to glucose among seven sugars tested (i.e., mannitol, galactose, lactose, maltose, sucrose, and fructose). The proposed formation of hydrogen-bonded complexes during the glucose sensing was supported by our energy calculation. Meanwhile, this organogel exhibits pH-response. Importantly, this LMOG could be conveniently recycled and thus be reused.

A novel glucose/pH responsive low-molecular-weight organogel of easy recycling.

The invention relates to a palladium-catalyzed synthesis method of a diketone compound, which comprises the following step: reacting a dinitrile compound and aryl trifluoroborate in solvent in the presence of a palladium catalyst, a nitrogen-containing ligand and trifluoroacetic acid to prepare the diketone compound through one step The synthesis method has the advantages of mild reaction conditions, high product yield, simple operation and the like, provides a new chemical reaction route for synthesis of the diketone compound, and has favorable implementation values and industrial application prospects

Preparation method of aromatic diketone compound

The invention provides a method for synthesizing an aryl or heteroaryl substituted quinazoline compound. According to the method, a copper compound and an iron compound serve as a bicomponent catalyst, and o-aminobenzyl alcohol and an aldehyde compound are enabled to react in the presence of an ammonium compound, alkali, organic ligands and TEMPO (Tetramethylpiperidine Oxide), thereby obtaining the aryl or heteroaryl substituted quinazoline compound. According to the method provided by the invention, the operation is simple, and the yield and purity of the product are high, so that the method has good industrial application potential.

Method for synthesizing aryl or heteroaryl substituted quinazoline compound

Method for synthesizing quinazolino indazole derivatives

The invention relates to a synthetic method of Beta-hydroxyl selenide compound. The method includes: in organic solvent, in the presence of catalyst and alkali, allowing halogenated compound to react with elemental Se and epoxy compound to obtain Beta-hydroxyl selenide compound. The synthetic method has the advantages that reaction is simple, operating is simple, yield is high, the method is a novel one, a novel synthetic route is provided for the synthesis of the Beta-hydroxyl selenide compounds, and the method has good scientific research value and industrial potential.

Huang Xiaobo

Papers

A novel glucose/pH responsive low-molecular-weight organogel of easy recycling.

Preparation method of aromatic diketone compound

Method for synthesizing aryl or heteroaryl substituted quinazoline compound

Method for synthesizing quinazolino indazole derivatives

Synthetic method of Beta-hydroxyl selenide compound