Synthesis and Properties of Novel Copolymers Based on Fluorene and Thiophene

1 Results In this contribution we present the synthesis and characterization of novel copolymers based on fluorene and thiophene (see Scheme 1).They were synthesized by the Pd-catalyzed Suzuki coupling reaction of 9,9-dihexylfluorene-2,7-diboronic acid bis(1,3-propanediol) ester and 3-substituted (R=3-methylbutyl,hexyl,2-(pyren-1-yl)vinyl) 2,5-dibromothiophenes and characterized by GPC,IR and NMR techniques.UV-vis absorption,photoluminescence (PL) and electrochemical behavior of these polymers were also studied.Though a similar absorption was observed in solutions and thin films of the polymers,the maximum at 400 nm for FIPT and F3HT and at 390 nm FPyT,PL of FPyT thin film differs from those of FIPT and F3HT thin films.They exhibited an intense green PL emission,whereas PL emission of FPyT thin film was orange with a red-shifted maximum compared with FIPT and F3HT indicating pronounced aggregation of FPyT in the solid state.Cyclic voltammetry showed that all the polymers are reversibly oxidized and reduced.A similar electrochemical behavior was observed for FIPT and F3HT whereas a higher electron affinity was estimated for FPyT.     

Synthesis of Novel Low-band-Gap Thiophene-based Oligomers and Copolymers

1 Results In this contribution,the synthesis and characterization of low-band-gap oligothiophenes and copolymers based on fluorene and thiophene units are reported.First,5,5′-dibromo derivative of 1 was synthesised and used as a building block for synthesis of quinquethiophene and septithiophene analogues of 1 and the synthesis of a novel low band-gap polymer - soluble alternating copolymer 3,which was prepared by the Suzuki coupling of 5,5′-dibromo derivative of 1 with bis(propane-1,3-diyl) 9,9-bis(2-ethylhexyl)fluorene-2,7-bisboronate.Further,two soluble random copolymers 4 of 3-(3-methylbutyl)thiophene with 3-[2-(pyren-1-yl)vinyl]thiophene were prepared by Grignard metathesis copolymerization of corresponding dibromo monomers.See Fig.1.     

Synthesis and Spectrum Properties Studies of Tropolone Azo

1 Results Tropolone,2-hydroxy-2,4,6-cycloheptatrienone,an isomer of benzoic acid,a seven-membered,non-benzenoid aromatic molecule possessing three double bonds conjugated with a carbonyl group.The studies of tropolone forms complexes[1] with many metals became more important because of their potential application in the field of material science,agriculture and medicine.In the course of our studies on the chemistry of 5-substituted tropolone derivatives[2],the synthesis of new tropolone azo derivatives through the coupling of diazotized 2-amino-4-nitropheno-6-sulfoacidphenol and tropolone is described.it's structures were confirmed by elemental analysis,IR and 1H NMR,13C NMR and chromogenic properties and UV-Vis absorption spectra were investigated under different pH condition.Experimental results show that the synthesized derivatives can be used as new indicators and host molecules.Tropolone-azo (A)was prepared by reacting tropolone and 2-amino-4-nitropheno-6-sulfoacidphenol in a 1:1 molar ratio in water.See Fig.1.     

Triphosgene as an Efficient and Electrophilic Reagent for the One-pot Synthesis of Sulfonylsemicarbazids

1 Results Sulfonylsemicarbazide derivatives are important compounds as blowing agents in cellular rubber and plastics[1]. Different methods for the preparation of these compounds are reported. For example, sulfonylsemicarbazides are prepared by reaction of sulfinic acid salt with azodicarbonamide in water[2] and reaction of sulfonylchloride with semicarbazide[3-4]. In these methods the yields of products are not high[3-4], the solvent such as pyridine is toxic and also the sulfinic acid salt as starting material is not commercially available[2]. Recently, triphosgene [bis(trichloromethyl)carbonate], a crystalline solid which can be easily handled, was reported as a safe stable reagent[5]. It was successfully utilized to the synthesis of large variety of organic compounds[6].     

Dosing of Reagents and Solid Supports as Tablets

During the latest decade, the intensive investigation into the solid-phase synthesis of small organic molecules, as well as the use of polymer-supported reagents and catalysts for solution-phase organic synthesis has lead to paradigm shifts in many areas of chemistry. This has particularly been the case within the fields of biological and medicinal chemistry where the parallel synthesis of discrete molecules （in series or larger libraries）, either by manual or automated methods, has been implemented as a key technology/methodology in the preparation of compounds for biological evaluation.     

New Approach to the Synthesis of C-Glycosides

C-glycosides are important carbohydrate mimetics and have gained considerable attention because ot their attractive biological activities as pharmaceutical targets and their resistance to enzymatic degradation in vivo. Consequently, a large number of C-glycosides have been synthesized for their bioactivity investigation, and various synthetic methodologies have been developed. As a continuation of the synthesis of novel C-glycoside derivatives using exo-glycals as the precursor, we wish to present herein new approaches to the synthesis of C-aryl aminoglycoside via the 1,3-dipolar cycloaddition （Scheme 1 ） and C-disaccharides by Suzuki cross-coupling reaction （Scheme 2）, and the synthesis of dihydropyrimidinonyl （DHPM） glycoside by the three component Biginelli reaction （Scheme 3）.     

Metallafurans and their synthetic chemistry金属呋喃及其合成化学

Based on isolobal analogy,the definition of metallafuran was described and its synthetic chemistry was briefly summarized.In the structure of furan,when one of CH groups was replaced by an isolobal metal fragment ML n(M=metal;L=ligand),the corresponding organometallic complex was called metallafuran,which should be two possible isomers called a-metallafuran(metal fragment at a-carbon of original furan)and b-metallafuran(metal fragment at b-carbon of original furan).As an organometallic complex,a-metallafuran has two resonant forms:one can be viewed as carbonyl coordinated vinyl metal complex and the other can be viewed as alkoxymetal carbene.Therefore,a-metallafuran was also called chelated vinyl ketone metal complex or oxametallacyclopentadiene in the early literatures.For synthesis of metallafurans,a-metallafurans were very common and easily prepared,for example,from alkynes insertion into acyl metal complexes and so on.While there were rare examples reported for b-metallafurans.In this mini review,the synthetic chemistry of metallafuran was mainly focused on its formation mechanism.     

Oriented growth and assembly of zeolite crystals on substrates

The aligned array and thin film of zeolites and molecular sieves Possess a variety of potential applications in membrane separation and catalysis, chemical sensors, and microelectronic devices. There are two main synthesis methods for manufacturing the aligned arrays and thin films of zeolites and mo- lecular sieves, i.e. in situ hydrothermal reaction and self-assembly of crystal grains on substrates. Both of them have attracted much attention in the scientific community worldwide. A series of significant progress has been made in recent years. By the in situ hydrothermal synthesis, the oriented nucleation and growth of zeolite and molecular sieve crystals can be achieved by modifying the surface properties of substrstes or by changing the composition of synthesis solutions, leading to the formation of uni- formly oriented muIticrystal-aligned arrays or thin films. On the other hand, the crystal grains of zeo-lites and molecular sieves can be assembled onto the substrste surface in required orientation using different bondages, for instance, the microstructure in the array or thin film can be controlled. This review is going to summarize and comment the significant results and progress reported recently in manufacturing highly covered and uniformly aligned arrays or thin films of zeolites and molecular sieves. It involves （1） in situ growth of highly aligned zeolite arrays and thin films via embedding func-tional groups on the substrste surface, modifying the surface microstructure of substrates, as well as varying the composition of synthesis solutions; （2） assembly of zeolite and molecular sieve crystals on various substrates to form aligned arrays and thin films with full coverage by covalent, ionic, and in-termolecular coupling interactions between crystals and substrates; （3） coupling surface assembly with microcontact printing or photoetching technique to produce patterned zeolite arrays and thin films. Finally, the functionality and applications of zeolite arrays and thin films are briefly intr     

Studies on the interactions of 2,5-diphenyl 1,3,4-oxadiazole and 2,5-diphenyl 1,3-oxazole with β-cyclodextrin

Interactions of 2,5-diphenyl 1,3,4-oxadiazole (PPD) and 2,5-diphenyl 1,3-oxazole (PPO) with β-cyclodextrin (β-CD) are studied by 1H-NMR and steady-state fluorescence measurements, and the stoichiometries and the association constants are estimated. It is found that the hydrophobic interaction is the main driving force for the formation of inclusion complexes of PPD and PPO with β-CD. In the presence of aliphatic alcohols (from 1-propanol to 1-pentanol), PPD and PPO transfer from the CD cavity to the aqueous phase. Quenching experiments of PPD and PPO by iodide further prove the above conclusions. The results suggest that stereo effect is the crucial factor to the inexistence of nanotube in PPD (or PPO)-β-CD systems.     

Enzyme-Mediated Hydrolysis of Poly（ethylene glycol）-Supported Carbonates

Enzymatic kinetic resolution of racemic alcohols or esters is known as a useful method for the preparation of optically active secondary alcohols. However, the work-up including the separation of the mixture of the remaining substrate and the resulting compound spend a lot of time and waste much amount of solvents. On the other hand, organic synthesis based on polymer supports has made rapid progress. Although the methodology is potentially useful for the easy separation of compounds obtained by the enzymatic reaction, there have been relatively few reports on enzymatic resolutions of using a polymer so far. We have noticed that using a watersoluble polymer could be suitable for enzymatic transformation. Here, we report the first example of an enzyme-mediated enantioseleetive hydrolysis of poly（ethylene glycol）（PEG）-supported substrates with a carbonate moiety to afford optically active compounds, and the method enables us to achieve the easy separation of the products. See Scheme 1.     

Enzyme-Mediated Hydrolysis of Poly(ethylene glycol)-Supported Carbonates

1Introduction Enzymatic kinetic resolution of racemic alcohols or esters is known as a useful method for the preparation of optically active secondary alcohols. However, the work-up including the separation of the mixture of the remaining substrate and the resulting compound spend a lot of time and waste much amount of solvents. On the other hand, organic synthesis based on polymer supports has made rapid progress. Although the methodology is potentially useful for the easy separation of compounds obtained by the enzymatic reaction, there have been relatively few reports on enzymatic resolutions of using a polymer so far. We have noticed that using a watersoluble polymer could be suitable for enzymatic transformation. Here, we report the first example of an enzyme-mediated enantioselective hydrolysis of poly(ethylene glycol)(PEG)-supported substrates with a carbonate moiety to afford optically active compounds, and the method enables us to achieve the easy separation of the products[1]. See Scheme 1.     

Sulfoalkyl ether β-cyclodextrin derivatives synthesized by a single step method as pharmaceutical biomaterials

We report a simple ＂one pot＂ single step method to synthesize sulfoalkyl ether β-cyclodextrin （β-CD） derivatives in aqueous solution, which avoids the limitations associated with commonly used organic synthesis of such derivatives including multi-step reactions, use of expensive, toxic, and often environmentally hazardous organic solvents and/or reagents. Using this method, we obtained sulfopropyl and sulfobutyl ethyl β-CDs. We characterized these two derivatives and evaluated their ability to enhance solubility of fluconazole, a commonly used antifungal drug with poor water solubility. Experimental results indicate that these derivatives are structurally analogous to some of the commercially available β-CD derivatives. More importantly, when they formed supramolecular inclusion complexes with fluconazole, they demonstrated similar, if not better, capacity to enhance fluconazole solubility compared with commercially available β-CD derivatives, suggesting that the simple ＂one pot＂ single step synthesis may provide an effective alternative approach to produce large quantity of β-CD derivatives as pharmaceutical biomaterials for medicinal applications.     

Mineralization of flue gas CO2 with coproduction of valuable magnesium carbonate by means of magnesium chloride

CO2 mineralization and utilization is a new area for reducing the CO2 emissions. By reacting with natural mineral or industrial waste, CO2 can be transformed into valuable solid carbonate （such as calcium carbonate or magnesium carbonate） with recovery of some products simultaneously. In this paper, a novel method was proposed to mineralize CO2 by means of magnesium chloride with small energy consumption. In this method, magnesium chloride was firstly transformed into magnesium hydroxide by electrolysis. The formed magnesium hydroxide showed high reactivity to mineralize CO2. In our study, even at low concentration, CO2 can be effectively mineralized by this method, which makes it possible to directly mineralize flue gas CO2, avoiding the expensive process of CO2 capture and purification. Moreover, valuable products such as hydromagnesite and nesquehonite can be recovered by this method. Because of the wide distribution of magnesium chloride in nature, largescale CO2 mineralization is potential by means of magnesium chloride.     

Superior machinability of steel enhanced with BN and MnS particles

The strategy that replacing part of MnS with BN was proposed in order to decrease the sulfur content in sulfur based free-cutting steel. The effects of BN and MnS inclusions on the microstructure and machinability of the steel were systematically investigated. The results show that most of the BN and MnS inclusions exist individually in the steel and only a small amount of them are in a composite state forming either isolated particles or clusters of particles. In the case of multi-phased steel, the theoretical calculation predicts that the volume of large BN particles should be 0.7 times of the volume of large MnS particles. The machinability of this type of BN and MnS alloy steel over a wide range of cutting speeds ranging from a low speed appropriate for drilling to a high speed appropriate for turning is confirmed as being equal to or superior to that of an MnS reference steel, even though the sulfur content in the composite steel is only half that of the MnS steel. The aptitude for cutting effect of 240 ppm nitrogen and 115 ppm boron in the composite steel is demonstrated to be equivalent or even better than 1000 ppm sulfur in MnS free-cutting steel.     

Synthesis of CuInS2 nanocrystals and their structural transformation triggered by ligand exchange

Chalcopyrite-type CulnS2 NCs was synthesized by the hot-soap method. Mixed solutions, Cul and InCl3 dissolved in the mixture of the tri-octylphosphite and 1-octadecene and the sulfur dissolved in tri-phenylphosphite, were used as source solutions; the hexadecylamine was additionally mixed as a surfactant before the reaction. It was observed that the product CulnS2 NCs structurally transformed from the chalcopyrite（CP）- or zincblende（ZB）- to the wurtzite（WZ）-type depending on the amount of the surfactant and a storage time after the surfactant addition. Very weak photoluminescence in the nearinfrared region was observed for the CP- or ZB-type NCs. This band was attributable to the electronhole recombination via defect levels. No photoluminescence was detected for the wurtzite-type NCs.     

Catalytically Active Metal Nanoclusters Inside Cross-linked Functional Polymers:An Overview

1 Results Metal (0) nanoclusters (MNs), "strange morsels of matter"[1], are nanosized systems that are crucial components of industrially relevant catalysts (e. g. NH3 synthesis, catalytic reforming of alkanes, etc.). In recent years MNs have attracted an unprecedented attention among researchers acting in University, Scheme 1 Graphical model for the generation of size-controlled Pd0 nanoclusters inside metallated resins.a) PdⅡ is homogeneously dispersed inside the polymerGovernmental Institutions and Industry[2] and when MNs are to be utilized for catalytic purposes, their dispersion onto suitable supports is mandatory. We have started in the early nineties a long-prospects project aimed at supporting the choice of employing cross-linked functional polymers as supports of M0 nanoclusters to give M0/CFPs catalysts suitable to be utilized in the liquid phase (Scheme 1[3]). The major prospects offered by these catalysts are a) facile preparation, b) multi-functionality (exemplified by the current industrial synthesis of methyl isobutyl ketone from acetone and dihydrogen), c) re-usability, d) lack of pyrophoricity, e) easiness in obtaining polymetallic nanoclusters or nanoaggregates[2], f) reasonable chemical, thermal and mechanical stability[2]. A thorough account on the synthesis, chemistry and catalytic activity of M0/CFPs materials is available in Ref.[2].     

Efficient synthesis of functionalized 2-pyridones by ytterbium chloride catalyzed tandem condensation

An efficient method was developed for the synthesis of arylidene heterobicyclic 3-cyano-2-pyridones via ytterbium chloride catalyzed tandem condensation of aromatic aldehydes,cyclic ketones,and cyanoacetamide.The conditions and scope of the reaction were investigated and a reaction mechanism was proposed.     

Acylation of nitriles to β-ketonitriles catalyzed by a heterometallic alkoxide cluster of neodymium and sodium： NdNa8（O^tBu）10（OH）

Catalytic acylation of nitriles with esters in the presence of 10 mol% NdNa8(OtBu)10(OH) is developed.The procedure is suitable for both enolizable and nonenolizable esters and affords β-ketonitriles in moderate to high yields.The heterometallic alkoxide cluster NdNa8(OtBu)10(OH) is structurally characterized by X-ray diffraction,and a mechanism for the production of β-ketonitriles using the cluster is proposed and verified.     

Synthesis of novel active ester ether resin and its effects on positive thermal CTP plates

A novel active ester ether resin, consisting of p-hydroxyphenylacetic acid and a mixed-phenol novolac resin, was produced by the addition of ethyl vinyl ether to a carbonyl novolac resin. This study investigated the conditions of its synthesis and characterized its structure using infrared and 1 H NMR spectroscopies, and gel-permeation chromatography. Its solubility in alkaline solution differed greatly before and after decomposition. The results of thermal gravimetric analysis confirmed the formation of an active ester ether resin of p-hydroxyphenylacetic acid and novolac resin. The resin had acidolysis activity at room temperature and pyrolysis activity at high temperatures (140-200°C) and could be used in the imaging layer of a positive thermal plate for computer-to-plate processes as an inhibitor/accelerator to improve its alcohol resistance, alkali resistance, sensitivity, lattice point reducibility, and developing tolerance.     

Experimental study on sulfur removal from ladle furnace refining slag in hot state by blowing air

In view of the present problem of sulfur enrichment in the metallurgical recycling process of ladle furnace (LF) refining slag, a simple and efficient method of removing sulfur from this slag was proposed. The proposed method is compatible with current steelmaking processes. Sulfur removal from LF refining slag for SPHC steel (manufactured at a certain steel plant in China) by blowing air in the hot state was studied by using hot-state experiments in a laboratory. The FactSage software, a carbon/sulfur analyzer, and scanning electron microscopy in conjunction with energy-dispersive X-ray spectroscopy were used to test and analyze the sulfur removal effect and to investigate factors influencing sulfur removal rate. The results show that sulfur ions in LF refining slag can be oxidized into SO₂ by O₂ at high temperature by blowing air into molten slag; SO₂ production was observed to reach a maximum with a small amount of blown O₂ when the temperature exceeded 1350℃. At 1370℃ and 1400℃, experimental LF refining slag is in the liquid state and exhibits good fluidity; under these conditions, the sulfur removal effect by blowing air is greater than 90wt% after 60 min. High temperature and large air flow rate are beneficial for removing sulfur from LF refining slag; compared with air flow rate, temperature has a greater strongly influences on the sulfur removal.