Synthesis and characterization of quaternized poly(phthalazinone ether sulfone ketone)for anion-exchange membrane

Chloromethylated poly（phthalazinone ether sulfone ketone） （CMPPESK） was prepared from poly（phthalazinone ether sulfone ketone） （PPESK） using chloromethyl octyl ethers （CMOE） with lower toxicity as chloromethylated regent. CMPPESK was soluble in N-methyl-2-pyrrolidone （NMP）, N,N-dimethylacetamide （DMAc） and chloroform. Quaternized poly（phthalazinone ether sulfone ketone） （QAPPESK） was prepared from CMPPESK by quaternization. QAPPESK had excellent solvent resistance, which was only partly soluble in sulfuric acid （98%） and swollen in N,N-dimethylformamide （DMF）. The vanadium redox flow battery （V-RFB） using QAPPESK anion-exchange membrane had better performance with 88.3% of overall energy efficiency.

HALOMETHYLATION OF POLYSTYRENE AND SUBSEQUENT PYRIDINATION VIA A HOMOLYTIC PATHWAY

Chloromethylation of polystyrene （PS） with two different chloromethylating systems methylal/thionyl chloride and paraformaldehyde/trimethylchlorosilane was studied. Soluble chloromethylated polystyrene with a degree of substitution of 89% was obtained. The Conant-Finkelstein reaction on the chloromethylated PS afforded soluble iodomethylated polystyrene with a degree of substitution as high as 96%. The reaction conditions of Minisci were employed to radically pyridinate PS via its iodomethylated derivative. Polyelectrolytes were formed which could be converted to normal polymers by treatment with a 20% aqueous solution of NaOH.

Cationic ring-opening polymerization of 3,3-bis(chloromethyl)oxacyclobutane in ionic liquids

Cationic ring-opening polymerization of 3,3-bis（chloromethyl）oxacyclobutane catalyzed by BF3.OEt2 was carded out in ionic liquids [bmim]BF4 and [bmim]PF6. The influences of BCMO concentration and molar ratio of BCMO/BF3.OEt2 on the molecular weights and yield of PBCMO were investigated. The polymerization in ionic liquids proceed to high conversions, although molecular weights are limited, similar to polymerization in organic solvent such as CH2Cl2. Follow a viewpoint of green chemistry, we feel ionic liquid [bmim]BF4 is superior to [bmim]PF6. Extracting [bmim]PF6 from the product using organic solvent as extractant limits its advantage as a green reaction media.

RING OPENING POLYMERIZATION OF （CHLOROMETHYL）THIIRANE BY RARE EARTH COORDINATION CATALYSTS Ⅲ．HOMOPOLYMERIZATION OF （CHLOROMETHYL）THIIRANE AND ITS POLYMERIZATION KINETICS

Ring opening polymerization of (chloromethyl) thiirane (CMT) usingrare earth coordination catalysts has been investigated for the first time: Ithas been found that binary rare earth coordination catalyst composed of rareof phosphonate and trialkyl aluminum are effective catalysts for the polymerization of (chloromethyl)thiirane with high yield. Kinetic studies showed that the polymerization rate is of first order with respect to both monomer concentration and catalyst concentration. The antivation energy of the polyimerization reaction is 28.4kJ/mol.

The Chloromethylation Reaction of Substituted Titanocenes(η~5-C_5H_5)(η~5-C_5H_4CRR'C_6H_4X)TiCl_2

The chloromethylation reaction of substituted titanocenes (η~5-C_5H_5)(η~5-C_5H_4CRR'C_6H_4X)TiCl2 1 in the presence of polyformaldehyde and dry hydrogen chloride isreported.

GRAFTED STYRENE-DIVINYLBENZENE COPOLYMERS CONTAINING BENZALDEHYDES AND THEIR WITTIG REACTIONS WITH VARIOUS PHOSPHONIUM SALTS

A chloromethylated styrene-divinylbenzene copolymer support system functionalized with 4-benzaldehyde and 2-benzaldehyde was prepared. The degree of functionalization with aldehyde groups is well suited for the subsequent use of the products as Wittig reagents. The polymer bound aldehyde was reacted with Wittig reagents to give olefin groups grafted on styrene-divinylbenzene copolymers. The reactions were carded out in phase transfer catalysis conditions. A simple procedure for the calculation of the degree of functionalization and the statistical modeling of the structural repetitive unit of the copolymer are reported.

2-FURFURYLKETONES FROM 2-(CHLOROMETHYL)FURAN AND LITHIUM TRIALKYLALKYNYLBORATES

2-(Chloromethyl)furan as an electrophile attacks lithium trialkylalkynylborates,followed by the oxidation with H_2O_2 under basic conditions to afford 2-furfurylketones in good yields.

Preparation of Single Substituted Phenyl Porphyrins Form <i>Meso</i>-Tetraphenyl Porphyrin-Synthetic Example from Symmetric Porphyrin into Asymmetric Porphyrins

Two asymmetric porphyrins, 5-(4-chloromethylphenyl)-10, 15, 20-triphenyl porphyrin and 5-(4-formylphenyl)-10, 15, 20-triphenyl porphyrin, were successfully prepared by the symmetric meso-tetraphenyl porphyrin and relative molecular configurations and properties were characterized by spectral determinations. This work presented an example for synthesis of asymmetric porphyrin derivatives from the symmetric porphyrin. Both asymmetric porphyrins are reactive in molecular assembly, the concerned reactions including alkylation with Grignard reagents, etherification with alcohols, aldol condensation and Mannich reaction for modification and enhancing their functionality. In this work, the reaction conditions were improved, synthetic strategy and route were confirmed.

Ring-opening Polymerization of Chloromethyl Thiirane with Catalytic Systems Composed of Lanthanide Compound and Ethyl Aluminum Sesquichloride

The Ziegler-Natta type catalytic systems composed of lanthanide compound and ethyl aluminum sesquichloride are effective to convert chloromethyl thiirane to polymer of molecular weight ca. 10,000. The effects of rare earth element and ligand were studied.

Selective adsorption of silver ions from aqueous solution using polystyrene-supported trimercaptotriazine resin

Tdmercaptotriazine-functionalized polystyrene chelating resin was prepared and employed for the adsorption of Ag（I） from aqueous solution. The adsorbent was characterized according to the following techniques： Fourier transform infrared spectroscopy, elemental analysis, scanning electron microscopy and the Brunauer-Emmet-Teller method. The effects of initial Ag（I） concentration, contact time, solution pH and coexisting ions on the adsorption capacity of Ag（I） were systematically investigated. The maximum adsorption capacity of AgO） was up to 187.1 mg/g resin at pH 0.0 and room temperature. The kinetic experiments indicated that the adsorption rate of Ag（I） onto the chelating resin was quite fast in the first 60 rain and reached adsorption equilibrium after 360 min. The adsorption process can be well described by the pseudo second-order kinetic model and the equilibrium adsorption isotherm was closely fitted by the Langmuir model. Moreover, the chelating resin could selectively adsorb more Ag（I） ions than other heavy metal ions including： Cu（Ⅱ）, Zn（Ⅱ）, Ni（Ⅱ）, Pb（Ⅱ） and Cr（Ⅲ） during competitive adsorption in the binary metal species systems, which indicated that it was a highly selective adsorbent of Ag（I） from aqueous solution.

Facile Synthesis of Functional Poly (ε-caprolactone) via Janus Polymerization

Functionalized aliphatic polyesters attract increasing attentions as biocompatible and biodegradable polymers with broad applications in biological science. In this contribution, we propose a facile and controllable synthetic technique for functional poly(ε-caprolactone)(PCL) via Janus polymerization, which comprises cationic ring-opening copolymerization (ROP) of ε-caprolactone (CL) with 3,3-bis(chloromethyl)oxacyclobutane (CO) and (coordinated) anionic ROP of CL at a single propagating chain by rare earth metal triflates (RE(OTf)3)and propylene oxide, thus generating block copolymers in one step. The compositions of the copolymers of poly(CLb-(CL-r-CO)) can be modulated by various RE(OTf)3. Scandium triflate catalyzes Janus polymerization to yield the copolymers containing the highest CO contents among all the RE(OTf)3 catalysts used with complete conversion of CL. The chlorine in CO repeating units is ready to be transferred into azide group which affords the modification sites to react with 9-ethynyl-9-fluorenol and mPEG-alkyne, respectively, via copper(I)-catalyzed azide-alkyne cycloaddition reaction with quantitative conversions of azides, as confirmed by FTIR analyses. According to NMR and SEC analyses, copolymers (PCC-g-PEG) bearing a homo-PCL block and a PEG-grafted block of poly(CO-co-CL) demonstrate well-defined chemical structures. The investigations on thermal properties reveal the strong phase separation between PCL and PEG blocks. The amphiphilic PCC-g-PEG is able to sei住assemble into micelles in aqueous solution while cylindrical and lamellar morphologies are observed in bulk. We provide an efficient protocol to synthesize functional PCL combining onestep Janus polymerization and precise post-polymerization click reaction.

Chloromethylation and Quaternization of Poly(aryl ether ketone sulfone)s with Clustered Electron-rich Phenyl Groups for Anion Exchange Membranes

Ion segregation is critically important for achieving high ion conductivity for anion exchange membranes(AEMs).Herein,a new bisphenol monomer bearing ten electron-rich phenyl groups was designed and polymerized with various amounts of electron-deficient 4,4′-dihydroxydiphenylsulfone and 4,4′-difluorobenzophenone to yield dense and selective reaction sites for chloromethylation and quaternization.As the most challenging step,chloromethylation was optimized by tuning the reaction temperature,reaction time,and reactant ratios.Ion exchange capacity,water uptake,anion conductivity,mechanical stability,and alkaline stability of the resulting AEMs were characterized in detail.It is found that chloromethylation reaction needed to be carried out at low equivalent of chloromethylation agents to avoid undesirable crosslinking.The QA-PAEKS-20 sample with an IEC of 1.19 mmol·g^-1 exhibited a Cl^–conductivity of 11.2 mS·cm^-1 and a water uptake of 30.2%at80°C,which are promising for AEM applications.

Chloromethylation of 2-chloroethylbenzene catalyzed by micellar catalysis

The chloromethylation reaction of 2-chloroethylbenzene was performed successfully by micellar ca-talysis in the biphasic oil/water system. The effects of anionic, cationic and non-ionic surfactants on the reaction were compared. The mechanism of chloromethylation reaction and the mechanism of micellar catalysis were investigated. The results show that the micellar catalysis is an effective way to realize the chloromethylation of 2-chloroethylbenzene, and the cationic surfactant shows the most effectiveness. The longer the hydrophobic chain of the cationic surfactant is, the better the catalysis effect will be, and the addition of inorganic electrolyte into the aqueous phase can markedly promote the catalysis effect.

One-Pot Synthesis of Chloromethylated Mesoporous Silica Nanoparticles as Multifunctional Fillers in Hybrid Anion Exchange Membranes

Chloromethylated mesoporous silica nanoparticles （CM MSN） were synthesized through co-condensation of tetraethoxysilane and （chloro） phenyltrimethoxysilane precursors using hexadecyl trimethyl ammonium bromide as template.With the addition of the particles into chloromethylated poly （ether ether ketone） （PEEK）,the hybrid membranes were prepared by a solution-casting method after complete quatemization of the casting solution.The successful synthesis of the particles was verified by transmission electron microscopy,X-ray diffraction and Fourier transform infrared spectroscopy while the effect of CM MSN incorporation on membrane performance including thermal stability,mechanical strength and hydroxide conductivity was investigated by thermal gravimetric analysis,electronic stretching machine,alternating-current impedance and so on.Owing to the large pore volume and high surface area of the particles,the hybrid membranes exhibited enhanced hydroxide conductivity （88.7% increase at 60 ℃,100% RH with 5.0 wt% filling content） due to an increase in ion concentration and optimization of the channel morphology.Besides,higher mechanical strength,thermal and dimensional stability of hybrid membranes were obtained compared with those of the imidazolium PEEK membrane.

SYNTHESIS, RESOLUTION AND PROTECTION OF 4-CYCLOAMINOMETHYL PHENYLALANINES

In the development of new peptide drugs, it is an important way to synthesize the analogs of bioactive peptide. There are different methods to obtain the analogs, including: (ⅰ) changing the backbond structure of a peptide; (ⅱ) changing the amino acid residues and (ⅲ) introducing D-amino acids into a peptide. In some cases, to get high potent analogs of a peptide, unnatural amino acids are needed.

Li^＋ Ion Attachment to Chloromethyl and Chlorofluoromethyl Peroxyl Radicals： Structures and Properties, of CHnCl3-nO2-Li^＋ and CFnCl3-nO2-Li^＋ （n=0-3） Complexes

The structures and stabilities of these still experimentally unknown CHnCl3-nO2-Li^＋ and CFnCl3-nO2-Li^＋ ions have been theoretically investigated by ab initio molecular orbital theory and density functional theory （DFT） in conjunction with the 6-311G（d,p）, 6-311 ＋G（d,p）, 6-311 ＋G（2d,p） and 6-311 ＋G（2df,2p） basis sets. The optimized geometries, chemical bonding and NBO analysis indicate that these complexes of CHnCl3-nO2-Li^＋ and CFnCl3-nO2- Li^＋ exist as ion-dipole molecules. The calculated affinity energies of these species exceed 41.9 kJ/mol, which are large enough to suggest the possibility that these title complexes could be detected as stable species in gas phase by Li^＋ ion attachment mass spectrometry.

Studies on Ring-Opening Polymerization of Chloromethyl Thiirane with Rare Earth Catalysts and Functional Resins Synthesized therewith

Studies on ring-opening polymerization of chloromethyl thiirane with rareearth catalysts and functional resins synthesized therewith were reviewed.

Anion Exchange Membranes Based on Chloromethylation of Fluorinated Poly（arylene ether）s

This report details the properties of fluorine-containing anion exchange membranes（AEMs） synthesized by chloromethylation and quaternization of fluorinated poly（arylene ether）s（FPAEs） based on decafluorobiphenyl and bisphenol A. Meanwhile, we compared their properties with those of their non-fluorinated counterparts, Udel-based AEMs. The reactivity of the chloromethylation of fluorinated poly（arylene ether）s was lowered by the strong elec- tron-withdrawing group, per-fluorinated biphenyl residue. Therefore higher temperature, more chloromethylation reagent, and longer reaction time were needed in the chloromethylation of FPAEs. Because of the hydrophobicity of fluorine, the swelling of FPAEs was depressed. In the FPAE-based AEMs, the water uptake of FPAE-1 membrane（F-1） was just 30%. There is a strong correlation between water uptake and conductivity for both Udel- and FPAE-based AEMs. Among all the membranes, the water uptake and the conductivity of FPAE-3 membrane（F-3） could reach up to 100% and 13.47 mS/cm respectively at 30 ℃. The mechanical properties of FPAE-based AEMs at room tempera- ture were worse than those of Udel-based ones because of the weak intermolecular interaction caused by the low po- larizability of fluorine. However, their high temperature mechanical properties are better, which can be explained in terms of low swelling.

Chloromethyl pivalate based electrolyte for non-aqueous lithium oxygen batteries

A novel electrolyte with chloromethyl pivalate （CP） used as solvent was first reported for non-aqueous lithium-oxygen （Li-O2） batteries. Since there are no α-H atoms in the structure of CP, the CP based electrolyte in both superoxide radical solution and real LifO2 battery environment showed good chemical stability against superoxide radicals, which was confirmed by ^1H NMR and ^13C NMR measurements. Without a catalyst in the cathode of Li-O2 batteries, the batteries showed high specific capacity and cycling stability.