Synthesis and Self-assembling of Coumarin-based Low-molecular Weight Organogelators

Four coumarin derivatives（4a-4d） with different alkoxy chains were synthesized. It was found that compound 4d showed a better gelation ability than the other compounds, for example, it could self-assemble into organogels in various organic fluids via ultrasound treatment or heating-cooling process, whereas compound 4c could only gel in a few mixed solvents and compounds 4a, 4b could not form organogel. The results from fluorescent and FT-IR spectra indicate that π-π interaction had an effect on the formation of the organogels of compound 4d besides H-bonding and van der Waals interaction, which were the driving forces for the self-assembling of compound 4c in gel state. The gel of compound 4d in toluene could emit strong fluorescence under UV irradiation and the [2＋2] cyclo-addition was suggested by ^1H NMR and fluorescence spectroscopy. This light-sensitive organogel might find application in optical materials.

2,5-Dialkoxylphenyl-l,3,4-oxadiazoles as efficient organogelators and their self-assembling property

Four 2,5-dialkoxylphenyl-l,3,4-oxadiazoles are shown to be efficient organogelators. These com- pounds readily form stable gels in many organic solvents and their gelation property as well as supramolecular structures were investigated by scanning electron microscopy （SEM）, X-ray diffraction （XRD）, 1H nuclear magnetic resonance （1H NMR）, and ultraviolet-visible spectroscopy （UV-vis）. The results indicate that the gelator molecules self-assemble into gels with elongated fibrous networks and layer structures, and van der Waals interaction is the main driving force.

A phase-selective,bis-urea organogelator with a curved bis-naphthalene core

A phase-selective,bis-urea organogelator with a curved bis-naphthalene core was synthesized and characterized.This gelator is capable of gelating a variety of hydrocarbons and oils.The resulting gels have been characterized by rheology,SEM,and molecular modelling.The gelator can be applied in the powder form for the recovery of a thin layer of petrol oil spill in water.

Self-Assembly of Schiff Base Organogelator with Enhanced Fluorescence Emission

A new organogelator based on Schiff base derivative has been designed and synthesized.It can be employed as building blocks to fabricate organic nano-or micro-structures.It shows excellent self-assembling properties.It could form stable gels with nanofiber structures in various organic solvents,such as n-butanol,benzyl alcohol,ethyl acetate,acetone,aniline.The gelation properties,structural characteristics and fluorescence of the gels were studied.Compared with the solution,the gel showed significantly enhanced emission.This organogel system can be used as a thermally driven fluorescence molecular switch.

Phase-Selective Gelators Based on p-Alkoxybenzoyl for Oil Spill Recovery and Dye Removal

Oil spills result in tremendous damage to the environment and ecosystem.In this study,several p-alkoxybenzoyl-based gelators(1,2a,2b,2c,3)synthesized from commercially available materials were designed for recovering oil from an oil–water mixture.Gels with remarkable gelation ability in various oils were characterized by nuclear magnetic resonance,Fourier transform infrared spectroscopy and X-ray diffraction to study the driving forces of self-assembly.Notably,these gelators could achieve the goal of recycling oil from the oil–water mixture at room temperature.In addition,gelator 2b could be used to remove toxic dyes from aqueous solutions with high efficiency.Therefore,these compounds were considered promising materials for oil spill recovery and dye removal due to their practicality and high efficiency.

Novel four-hydrogen-bond assembled oligoamide dimer with pyrazoline moieties and its photoluminescent properties

In this paper, the synthesis and characterization of a triarylpyrazoline modified four-H-bonded molecular duplex are described. Its molecular structure has been confirmed by ^1H NMR and ESI-MS. The duplex emits strong pure blue light peaking at 448 and 452 nm under UV photoexcitation in solution and solid state, respectively, and its relative photoluminescence quantum efficiency in solution is determined as 0.778 using quinine sulfate as reference. In concentration of 〉40 mmol/L, the duplex can gelate DMSO, and the organogel formed shows good pure blue photoluminescence too. This novel duplex, for its well-defined structure and efficient photoluminescence property, is a prospective candidate for pure blue electroluminescent emitter.

Organogels, hydrogels and bigels as transdermal delivery systems for diltiazem hydrochloride

In the present study,gel formulations of organogels,hydrogels,and oleo-hydrogel(bigels)were evaluated as transdermal drug delivery systems for diltiazem HCL(DH).Organogels were prepared using soya-bean oil(SO)as a solvent and span 60(Sp 60),cetyl alcohol(CA)or lecithinpluronic(PLO)as organogelators without and with different surfactants(2%w/w)namely span 80(Sp80),tween 20(T20)and tween 80(T80).On the other hand,hydrogels were formulated using Hydroxypropyl-methylcellulose(HPMC)polymer and bigels were prepared by mixing organogels with HPMC hydrogels.The prepared gels were analyzed microscopically,thermally by DTA and for pH,and viscosity.The effect of gelator used,surfactant types and pH of the sink on DH release from cellophane membrane was investigated.In addition,the DH permeability across the rabbit skin was evaluated.Finally,the in vivo performance of various gel formulationswas assessed based on the hypotensive effects of the drug using hypertensive albino male rat models.The microscopical analysis indicated that the solid fibers formed by gelator particles form the backbone of the organogels while bigels appeared as emulsion like.The addition of surfactants showed an increase in organogel viscosity.The thermal analysis of organogels indicated that the drug present in amorphous not in crystalline form.The release studies indicated that DH release from organogels,hydrogels and bigels could be controlled.The included surfactants decreased the DH release and permeation from organogels compared to those without surfactants using either Sp60 or CA.HPMC hydrogel and Bigels showed higher DH release and permeation rates when compared to organogels.The percent DH released in different pH values was in the following descending order:pH5.5>pH1.2>pH6.8>pH7.4.The in vivo antihypertensive activity of DH using different transdermal gels is arranged as following:hydrogels>PLO organogel>bigel>Sp 60 organogel.

Comparison of Chromatographic Performance for L-Phenylalanine-Derived Organic Phases on Silica by “Grafting from” and “Grafting to” Strategies

L-phenylalanine-derived polymerizable organogel, N’-octadecyl-Nα-(4-vinyl)-benzoyl-L-phenylalanineami- de (4) has been prepared according to the procedure described elsewhere. Compound 4 was successfully polymerized by surface initiated atom transfer radical polymerization (ATRP) from the initiator grafted silica particles (sil-poly4). It was also telomerized with 3-mercaptopropyltrimethoxysilane (MPS) and the telomer (T4) was grafted on to silica (sil-T4). TGA and elemental analysis measurement revealed that higher amount of polymer can graft by ATRP process than that of “grafting to” strategy. The results of 13C CP/MAS NMR measurement showed that the N-alkyl chain of the grafted polymers for both sil-poly4 and sil-T4 remained as less ordered gauche conformational form on silica surface and no inversion to trans form was occurred until temperature is increased up to 50?C. The retention of alkylbenzene samples showed that sil-poly4 prepared by “grafting from” method yielded extremely higher retention than conventional C18 phase however, sil-T4 prepared by conventional “grafting to” method showed lower retention than C18 phase. Aspects of molecular recognition were evaluated by the retention studies of a series of polycyclic aromatic hydrocarbons (PAHs) and aromatic positional isomers. We have observed sil-T4 yielded slightly higher selectivity for PAHs than sil-poly4 regardless the fact that it has low surface coverage and lower hydrophobic interactions. The enhanced selectivity observed for sil-T4 than C18 phases and sil-poly4 can be explained by the π - π interactions between the guest PAHs and carbonyl groups present in the polymer chain. In addition the aromatic moieties of compound 4 that aggregates through π - π interactions also contribute to the separation of PAHs for both sil-poly4 and sil-T4. The minimal π - π interactions between the carbonyl groups and guest molecules for sil-poly4 probably due to the presence of long chain initiator which restrict the polymer to form order thin layer over silica surface.

Fluoride-Responsive Organogel Based on Hydrazide Derivatives

An organogelator named N-[3-(hydroxy)-4-(dodecyloxy)-benzoyl]-N’ (4’-nitro-benzoyl) hydrazide (D12) was synthesized. It could form stable gels in some of the tested organic solvent. SEM images revealed that the molecules self- assembled into fibrous aggregates in the xerogels. The X-ray diffraction analysis showed that the xerogel exhibited a layered structure. FT-IR studies confirmed that intermolecular hydrogen bonding between C=O and N-H groups was the major driving force for gelation of organic solvents. The gel exhibited gel-sol transition and color change upon addition of F- . An extended conjugated system formed through the phenyl group and a five-membered ring based on intramolecular hydro-gen bonding between the oxygen atom near the deprotonation nitrogen atom and the other NH, which is responsible for the dramatic color change upon addition of F- .

Versatile Organogels of Aluminum Oxide Subnanosheets for Locking Solvents and Adhesion

Herein,we present a facile strategy to prepare versatile aluminum oxide subnanometer nanosheets with oleic acid and stearic acid ligands(OA-Al SNSs and SA-Al SNSs,respectively).The size effect endows subnanosheets with abundant acting sites,remarkable intermolecular interactions,and unique polymer-like properties,including flexibility,viscoelasticity,and sol-gel transitions,which is quite different from traditional inorganic materials.Consequently,subnanosheets could form freestanding organogels and OA-Al SNSs exhibit satisfying semisolidification of various solvents,making it an intriguing candidate for the safe storage and transportation of solvents.Furthermore,SA-Al SNSs exhibit excellent adhesive properties of high strength on diverse substrates,and it is easy to erase it without any damage,demonstrating the promising prospects in practical applications.

Reconfigurable and orthogonal stiffness-structure patterning of dynamically crosslinked amphigels

Patterning diversified properties and surface structure of polymer materials are of great importance toward their potential in biology,optics,and electronics.However,achieving both the patternability of stiffness and microstructure in a reconfigurable manner remains challenging.Here,we prepare amphigels crosslinked by dynamic disulfide bonds,which can be reversibly swollen by immiscible water or liquid paraffin.In the paraffingel form,the materials exhibited a high modulus of 130 MPa due to densified hydrogen bonds.Whereas swollen by water,the modulus fell over two orders of magnitude owing to the destruction of the hydrogen bonds.Via regionalized swelling of the solvents,well-controlled and rewritable soft/stiff mechanical patterns can be created.On the other hand,the dynamic exchange of the disulfide crosslinking enables mechanophoto patterning to fabricate sophisticated macrogeometries and microstructures.The reconfigurable stiffness-structure patterning can be manipulated orthogonally,which will create more application opportunities beyond conventional hydrogels and organogels.

Synthesis and ultraviolet/aggregation-induced emission investigation of novel tetraphenylvinyl hydrazone derivatives: efficient multimodal chemosensors for fluoride ion

Herein,three novel tetraphenylethylene hydrazone chemosensors TC12,SC16,and TC16 are prepared for the selective detection of F−.Two NH and one C=N units are incorporated into the sensors for better colorimetric responses,whereas the tetraphenyl unit is in charge of the aggregation-induced emission effect.Among them,compounds SC16 and TC16 form stable gels with some organic solvents.All the tetrahydrofuran/H2O solutions of the three compounds exhibit aggregation-induced emission effect,whereby the fluorescence emission increases by varying degrees with the volume of poor solvent water.Moreover,good aggregation-induced emission effects are observed in the self-assembly of SC16 and TC16.As a sample chemosensor,TC12 in tetrahydrofuran responds to F−selectively with high sensitivity,with the colorimetric and fluorometric detection limits of 8.25×10^(−7) mol·L^(-1) and 2.69×10^(−7) mol·L^(-1),respectively.The reversible gel-sol-gel phase transition and color changes indicate that both SC16-dimethyl sulfoxide and TC16-ethyl acetate gels specifically respond to F-with good sensitivity.The detection results are well supported by ultraviolet-visible spectroscopy,fluorescent spectroscopy,and 1H nuclear magnetic resonance.More importantly,the driving forces of gelation are visually clarified through the single crystal X-ray analysis of compound TOMe.

Scalable and Robust Bio-inspired Organogel Coating by Spraying Method Towards Dynamic Anti-scaling

Scaling usually causes serious problems in daily life and industrial production.Currently,developing passive anti-scaling coatings has shown promises to overcome this problem.In this work,we fabricated a scalable and robust bio-inspired organogel(BIO)coating,showing dynamic scale resistance in the oil/brine mixture.The oil layer of the BIO coating was utilized as a barrier to inhibit scale nucleation and reduce scale adhesion.The mechanical strength of the coating was optimized by regulating nanoparticle contents.Moreover,the universality of scale resistance was demonstrated by varying the types of nanoparticles,oils and scales.Compared with commercial pipeline materials,such as copper,this BIO coating significantly reduces scale deposition after 240-h scaling test(ca.93%reduction).Therefore,this study designs scalable and robust organogel coatings for sustainable scale resistance,which may be used for practical application in oil production.

Wet‑Spinning Knittable Hygroscopic Organogel Fibers Toward Moisture‑Capture‑Enabled Multifunctional Devices

Atmospheric moisture exploitation is emerging as a promising alternative to relieve the shortage of freshwater and energy.Efforts to exploit hygroscopic materials featuring flexibility,programmability,and accessibility are crucial to portable and adaptable devices.However,current two-dimensional(2D)or three-dimensional(3D)-based hygroscopic materials are dif-ficult to adapt to diverse irregular surfaces and meet breathability,which severely hinders their wide applications in wearable and programmable devices.Herein,hygroscopic organogel fibers(HOGFs)were designed via a wet-spinning strategy.The achieved fibers were composed of the hydrophilic polymeric network,hygroscopic solvent,and photothermal/antibacterial Ag nanoparticles(AgNPs),enabling hygroscopic capacity,photothermal conversion,and antibacterial.Owing to the good knittable feature,the HOGFs can be readily woven to adjusted 2D textiles to function as an efficient self-sustained solar evaporator of 4-layer woven HOGF device with a saturated moisture capacity of 1.63 kg m^(-2) and water-releasing rate of 1.46 kg m^(-2) h^(-1).Furthermore,the 2D textile can be applied as a wearable dehumidification device to efficiently remove the evaporative moisture from human skin to maintain a comfortable environment.It can reduce the humidity from 90 to 33.4%within 12.5 min.In addition,the introduction of AgNPs can also endow the HOGFs with antibacterial features,demonstrat-ing significant potential in personal healthcare.

Novel 1,2,3-triazole-based compounds： Iodo effect on their gelation behavior and cation response

Two new series of 1,2,3-triazole derivatives, with and without iodo substitution, were synthesized and their gelation properties were measured. It was found that the iodo substitution at position 5 of triazole ring could greatly enhance the gelation ability. Scanning electron microscopy and X-ray diffraction reveal that the structures of the organogels from iodo and hydrogenous gelators are totally different, lodo gels are selectively responsive to the stimuli of Hg2＋, whereas hydrogenous gels can respond to Hg2＋ and Cu2＋. Moreover, the reversible gel-sol transition of hydrogenous gels can be controlled by redox reaction or tuned with suitable chemicals. The single crystal analysis of reference compound （C2） suggests that there are intermolecular and intramolecular non-classical hydrogen bonding interactions but no π-π interaction in hydrogenous gelator. The great difference between the two series of compounds results from the iodo effect and implies the existence of halogen bonding interaction in the iodo compounds.

有机小分子自组装凝胶网络对准固态染料敏化太阳电池电子动力学的影响机制（英文）

本文合成了N,N'-1,5-戊二基双月桂酰胺作为有机小分子凝胶剂,并将其应用于准固态染料敏化太阳电池(QS-DSSC)的电解质材料中.通过偏光显微镜观察到凝胶剂分子在液态电解质中形成交联凝胶网络的原位自组装过程.一方面,凝胶网络对氧化还原电对物理扩散的阻碍效应,加速了电解质/TiO_2光阳极界面的电子复合.另一方面,Li+与凝胶剂分子的酰胺基团发生锂键相互作用,减少了Li+在TiO_2表面的吸附,使TiO_2薄膜内的电子传输加快,电子注入效率(ηinj)降低,TiO_2导带边发生负移.测试表明,凝胶电池的开路电压(Voc)、单色光转化效率(IPCE)和短路电流密度(Jsc)均低于液态电解质制备的染料敏化太阳电池(L-DSSC),与上述分析结果符合,且说明电解质/TiO_2光阳极界面电子复合起了主导作用.108°C的相转变温度保证了凝胶电解质的本征稳定性,使得准固态电池在50°C和一个太阳光照条件下连续1000 h的加速老化实验中表现出优良的光热稳定性.

Functional Organometallics

1 Results The lecture will address aspects of functional organometallics related to the development of novel organometallic materials.In chromium complexes of fused arenes-regio-and diastereoselectively accessible by chromium-templated benzannulation of arylcarbenes by alkynes[1]-a haptotropic migration of the chromium fragment along the π-face of fused arenes is controlled by both thermodynamics and the substitution pattern of the arene and the metal coligand sphere,and can be applied towards an organo...

Preparation of optical active polydiacetylene through gelating and the control of supramolecular chirality

Achiral diacetylene 10,12-pentacosadinoic acid (PCDA) and a chiral low-molecular-weight organogelator could form co-gel in organic solvent and it could be polymerized in the presence of Zn(II) ion or in the corresponding xerogel under UV-irradiation. Optically active polydiacetylene (PDA) were subsequently obtained. Supramolecular chirality of PDA could be controlled by the chirality of gelators. Left-handed and right-handed helical fibers were obtained by using Land D-gelators in xerogels respectively, and CD spectra exhibited mirror-image circular dichroism. The PDA in xerogel exhibited typical blue-to-red transition responsive to the temperature and pH, while the supramolecular chirality of PDA showed a corresponding change.

Nanomagnetic Organogel Based on Dodecyl Methacrylate for Absorption and Removal of Organic Solvents

A novel nanomagnetic organogel was synthesized by in situ emulsion polymerization-crosslinking method using dodecyl methacrylate(DDMA) and styrene(St) as monomers, divinylbenzene(DVB) as a crosslinking agent, azobisisobutyronitrile(AIBN) as an initiator, and Fe_3O_4 as a nanomagnetic particle. Modification of the network was carried out by inclusion of the multi-walled carbon nanotubes(MWCNT) into the organogel matrix. The structure of the nanocomposite was characterized using FTIR spectroscopy, SEM,TEM, TGA/DTG, VSM, and BET analysis. The effects of various parameters such as the amount of crosslinker, initiator, Fe_3O_4, and reaction time as well as monomer ratio on the oil absorption of the organogel were studied. The synthesized organogel can absorb about35.5, 22.1, 29.86, 14.58, 17.6, 15.3, and 13.7 g·g^(-1) of CHCl_3, toluene, CH_2Cl_2, hexane, crude oil, gasoline, and diesel oil, under the optimized polymerization conditions, respectively. The nanocomposite organogels can be easily separated by a magnetic field after absorption of organic solvents.

Supramolecular self-assembly of two-component systems comprising aromatic amides/Schiff base and tartaric acid

The gelating properties and thermotropic behaviors of stoichiometric mixtures of aromatic amides 1,2,and the aromatic Schiffbase 3 with tartaric acid(TA)were investigated.Among the three gelators,2-TA exhibited superior gelating ability.Mixture 2-TA exhibits a smectic B phase and an unidentified smectic mesophase during both heating and cooling runs.The results of Fourier transform infrared spectroscopy and X-ray diffraction revealed the existence of hydrogen bonding and rc-ninteractions in 2-TA systems,which are likely to be the dominant driving forces for the supramolecular selfassembly.Additionally,it was established that all of the studied gel self-assemblies and mesophases possess alamellar structure.The anion response ability of the tetrahydrofuran gel of 2-TA was evaluated and it was found that it was responsive to the stimuli of F,Cl,Br,I,AcO.