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Xiaochuan Z.,Chongqing Education College | Xiaochuan Z.,Key Laboratory of Applied Chemistry of Chongqing Municipality | Xiaochuan Z.,Chongqing Three Gorges University | Shaocheng C.,Chongqing Education College | And 14 more authors.
Science China Chemistry | Year: 2012

Chiral MnIII(salen) (Jacobsen's catalyst) was axially immobilized onto a new type of organic polymer-inorganic hybrid materialzirconium poly(styrene-isopropenyl phosphonate)-phosphate(ZPS-IPPA) with different linkage lengths and evaluated as catalysts for the epoxidation of unfunctionalized olefins. The results demonstrated that the prepared catalysts exhibited moderate to good activity and enantioselectivity in the asymmetric epoxidation of unfunctionalized olefins. Furthermore, the immobilized catalysts were relatively stable and could be conveniently separated from the reaction system by simple precipitation in hexane. Moreover, higher enantioselectivity was obtained with catalyst 2c than that of homogeneous counterpart catalyzed even after eight times. The excellent recycling of the catalyst was attributed to its structure feature of ZPS-IPPA which is different from either pure polystyrene or pure zirconium phosphates. © Science China Press and Springer-Verlag Berlin Heidelberg 2012.


Liu Z.,Southwest University | Liu Z.,Key Laboratory of Applied Chemistry of Chongqing Municipality | Fu X.,Southwest University | Fu X.,Key Laboratory of Applied Chemistry of Chongqing Municipality | And 4 more authors.
Journal of Organometallic Chemistry | Year: 2012

Chiral salen Mn(III) complex has been supported onto sulfoalkyl-modified zirconium poly(styrene-isopropenyl phosphonate)-phosphate and zirconium poly(styrene-phenylvinyl phosphonate)-phosphate (ZPS-IPPA and ZPS-PVPA) by axial coordination. The supported catalysts showed higher chiral induction for enantioselective epoxidation of styrene, α-methylstyrene and indene than its homogeneous chiral salen Mn(III). In addition, ZPS-PVPA-supported catalyst (4c), with a larger pore diameter, was found to be more active than ZPS-IPPA-based catalyst (3c). The influence of the linkage lengths on the catalytic performance was investigated. What's more, the catalysts were easily separated from the reaction systems and could be reused for several times without significant loss of catalytic activity. © 2012 Elsevier B.V. All rights reserved.


Tu X.,Southwest University | Tu X.,Key Laboratory of Applied Chemistry of Chongqing Municipality | Fu X.,Southwest University | Fu X.,Key Laboratory of Applied Chemistry of Chongqing Municipality | And 3 more authors.
Displays | Year: 2010

In order to develop novel electrochromic materials, a series of N-substituted phenothiazine derivatives (PDs) were synthesized via S N2 reaction and characterized by NMR, IR spectroscopy. Their electrochemical properties were investigated using cyclic voltammetry and their spectrochemical properties were examined by UV-vis spectroscopy. It was found that phenothiazine derivatives in electrochromic devices (ECDs) showed reversible, clear color changes on electrochemical process. An electrochromic effect was observed with a color change from colorless to red or green for the phenothiazine derivatives synthesized. The phenothiazine derivatives synthesized are promising candidate for visible electrochromic devices, for their outstanding electrochromic behaviors plus the inexpensive starting materials and short synthetic routes. © 2010 Elsevier B.V. All rights reserved.


Yu X.,Southwest University | Yu X.,Key Laboratory of Applied Chemistry of Chongqing Municipality | Fu X.-K.,Southwest University | Fu X.-K.,Key Laboratory of Applied Chemistry of Chongqing Municipality | And 3 more authors.
Gongneng Cailiao/Journal of Functional Materials | Year: 2010

In order to develop novel electrochromic materials, a series of N-substituted phenothiazine derivatives (PDs) were synthesized via SN2 reaction and characterized by 1HNMR, 13CNMR and IR. Their electrochemical properties and spectrachemical properties were examined by cyclic voltammetry and UV-Vis. It was found that PDs as anodic electrochromic material and viologen as cathode electrochromic material in the composite electrochromic devices (ECDs) showed reversible, clear color changes on electrochemical doping and dedoping process, and electrochromic effect was observed a color change from blue to red. The PDs synthesized are promising candidate materials for visible ECDs, for their outstanding electrochromic behaviors plus the cheap original stuff and short synthetic routes.


Huang X.,Southwest University | Huang X.,Key Laboratory of Applied Chemistry of Chongqing Municipality | Fu X.,Southwest University | Fu X.,Key Laboratory of Applied Chemistry of Chongqing Municipality | And 7 more authors.
Science China Chemistry | Year: 2013

Three new homochiral bis-diamine-bridged bi-Mn(salen) complexes were synthesized. Their catalysis on asymmetric epoxidation of α-methylstyrene, styrene and indene was studied with NaClO and m-CPBA as oxidants respectively. This homogeneous catalyst exhibited comparable catalytic activity and enantioselectivity to the Jacobsen's catalyst in the asymmetric epoxidation of unfunctionalized olefins. Furthermore, the catalyst could be conveniently recovered and reused at least five times without significant losses of both activity and enantioselectivity. Specially, it also could be efficiently used in large-scale reactions with superior catalytic disposition being maintained at the same level, which provided the potential for the applications in industry. The effect of axial bases, temperature and solvent on activity and enantioselectivity of the catalytic system were also studied. © 2013 Science China Press and Springer-Verlag Berlin Heidelberg.


Wu C.,Southwest University | Wu C.,Key Laboratory of Applied Chemistry of Chongqing Municipality | Wu C.,Chongqing Three Gorges University | Fu X.,Southwest University | And 5 more authors.
Tetrahedron | Year: 2011

New classes of O-acylation serine derived organocatalysts have been synthesized one-step by rational combination of serine with acyl chlorides at room temperature in trifluoroacetic acid. No protecting groups or chromatographic techniques are involved in any of the procedures, and certain combined serine-surfactant organocatalysts mediate the direct aldol reactions of ketones with a series of aromatic aldehydes to provide the aldol products in high yields (up to 99%) and enantioselectivities (up to 99% ee). The catalyst 1b can be easily recovered and reused, and without significant decrease of enantioselectivity was observed for five cycles. This novel catalyst can be efficiently used in large-scale reactions with the enantioselectivities being maintained at the same level, which offers a great possibility for application in industry. © 2011 Elsevier B.V. All rights reserved.


Gong C.-B.,Southwest University | Gong C.-B.,Key Laboratory of Applied Chemistry of Chongqing Municipality | Yang Y.-Z.,Southwest University | Yang Y.-Z.,Key Laboratory of Applied Chemistry of Chongqing Municipality | And 7 more authors.
Journal of Sol-Gel Science and Technology | Year: 2013

The primary objective of this work is to develop a photo-responsive surface molecularly imprinted polymer (SMIP) for 2,4-dichlorophenoxyacetic acid (2,4-D) to overcome the shortcomings of conventional molecularly imprinted polymers. A photo-responsive functional monomer was firstly prepared by covalent connecting azobenzene and 2,4-D. The photo-responsive SMIP was then prepared on SiO 2 nanoparticles via sol-gel process, and 2,4-D was removed via hydrolysis in acid. The SMIP shows specific affinity to 2,4-D and reversible uptake and release of 2,4-D upon alternate irradiation at 365 and 440 nm, respectively. The favorable binding strength of the imprinted receptor sites in the SMIP for 2,4-D is found to be 2.51 × 104 M-1. Density of receptor sites in the SMIP material is 10.59 μmol/g SMIP. The SMIP requires a shorter time to reach equilibrium than does the conventional molecularly imprinted polymer. The well-defined core-shell structure was clearly visualized by high resolution transmission electron microscopy. Graphical Abstract: [Figure not available: see fulltext.] © 2013 Springer Science+Business Media New York.


Du Q.-L.,Southwest University | Du Q.-L.,Key Laboratory of Applied Chemistry of Chongqing Municipality | Fu X.-K.,Southwest University | Fu X.-K.,Key Laboratory of Applied Chemistry of Chongqing Municipality | And 5 more authors.
Gongneng Cailiao/Journal of Functional Materials | Year: 2011

N-vinylimidazole, methyl bromoacetate and lithium trifluoromethanesulfonimide (LiTFSI) being the materials, poly(methyl 2-(3-vinylimidazolidin-1-yl) acetate trifluoromethanesulfonimide (PMVIm-TFSI) was synthesized by solution polymerization. Different composition of polymer electrolytes were prepared by blending PMVIm-TFSI with LiTFSI and poly(methyl methacrylate-co-vinyl acetate) (P(MMA-VAc)). 1H NMR, FT-IR, DSC, TGA, XRD, SEM and AC impedance results revealed that when PMVIm-TFSI was added into polymer electrolytes consisting of P(MMA-VAc)/LiTFSI, the thermal stability and ionic conductivity improved significantly, the maximum of which is 4.71×10-4S/cm at 30°C. Moreover, P(MMA-VAc)/PMVIm-TFSI/LiTFSI electrolyte membrane (transmittance≥90%) can be used as the ion-conductive layer material for electrochromic devices (ECDs), which revealed excellent electrochromic performance.


Wang C.,Southwest University | Wang C.,Key Laboratory of Applied Chemistry of Chongqing Municipality | Fu X.,Southwest University | Fu X.,Key Laboratory of Applied Chemistry of Chongqing Municipality | And 3 more authors.
Acta Chimica Sinica | Year: 2011

New types of supported catalysts were obtained by anchoring chiral salen Mn (III) complex on a series of alkoxyl-modified zirconium poly (styrene-phenylvinyl phosphonate) phosphate (ZPS-PVPA) in the text. All the prepared catalysts were characterized by FT-IR, UV-vis, XPS, SEM, TG and elemental analysis. The catalytic capabilities were investigated with m-CPBA as an oxidant and with indene and α-methylstyrene as substrates for asymmetric epoxidation of unfunctionalized olefins. Contrary to most of the literatures reported, the results showed that the heterogeneous catalysts 3a~3f exhibited excellent catalytic activities, and their conversions and ee values increased remarkably in the absent of N-methylmorpholine N-oxide (NMO) under the same catalytic conditions. Futhermore, these catalysts were easily separated and reused ten times without significant loss of activities.


Huang J.,Key Laboratory of Applied Chemistry of Chongqing Municipality | Fu X.,Key Laboratory of Applied Chemistry of Chongqing Municipality | Wang G.,Key Laboratory of Applied Chemistry of Chongqing Municipality | Li C.,Key Laboratory of Applied Chemistry of Chongqing Municipality | Hu X.,Key Laboratory of Applied Chemistry of Chongqing Municipality
Dalton Transactions | Year: 2011

A novel type of organic polymer-inorganic hybrid material layered crystalline zinc poly(styrene-phenylvinyl phosphonate)-phosphate (ZnPSPPP) was prepared by the reaction of styrene-phenylvinyl phosphonic acid copolymer with zinc acetate dihydrate and sodium dihydrogen phosphate. The ZnPSPPP were characterized by FT-IR, diffusion reflection UV-Vis, AAS, N2 volumetric adsorption, SEM, TEM and TG. Unexpectedly, the layered crystalline ZnPSPPP obtained was not synthesized with traditional methods as other zinc phosphonates, but with the ones for amorphous reactions without addition of any template. It can be deduced that the layered crystalline ZnPSPPP could have potential applications for heterogeneous catalyst supports. © The Royal Society of Chemistry 2011.

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