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Organic Chemistry Frontiers 2022年第1期9卷 102-108页

作者： Dongfeng Yang Chengyi Wang Yu Wang Guohua Liu Tanyu Cheng Rui Liu Joint laboratory of International Cooperation of Resource Chemistry of ministry of education Key Laboratory of Resource Chemistry of Ministry of Educationand Shanghai Key Laboratory of Rare Earth Functional MaterialsShanghai Normal UniversityShanghaiChina

The preparation of enantiomerically pure 1,4-oxazines remains a continuous challenge in synthetic chemistry because of their potential application in the total synthesis of morpholines.Herein,a one-pot asymmetric transfer hydrogenation/cyclization enantio-relay process catalyzed by Ru and Au bimetallic catalysts was developed.This enantio-relay process firstly allows the asymmetric transfer hydrogenation of alkynones to form chiral alkynols in the presence of(S,S)-mesityleneRuClTsDPEN(TsDPEN=N-(p-toluenesulfonyl)-1,2-diphenylethylenediamine)and then the chiral alkynols could be converted into 3,4-dihydro-2H-1,4-oxazines in moderate to good yields with excellent enantioselectivity retention accompanied by AuCl(PPh_(3))/AgNTf_(2) and HCOOH.A series of sulfonamide-tethered alkynones were well tolerated in this process.Mechanistic studies indicated that the alkynols formed in the first step were initially transformed into a methylenemorpholine intermediate when AuCl(PPh_(3))/AgNTf_(2) and HCOOH were added,which can be further isomerized into chiral 3,4-dihydro-2H-1,4-oxazines with the addition of a second HCOOH.This protocol offers not only a practical method to access 3,4-dihydro-2H-1,4-oxazines from alkynones in an enantioselective version,but also enriches the arsenal of gold chemistry from a mechanistic point of view.

关键词： process chiral hydrogenation

Oxygen vacancy-rich MoO_(3)nanorods as photocatalysts for photo-assisted Li-O_(2) batteries

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Journal of Advanced Ceramics 2023年第4期12卷 747-759页

作者： Guiru Sun Daming Yang Zexu Zhang Yan Wang Wei Lu Ming Feng key laboratory of functional materials Physics and Chemistry of the ministry of education Jilin Normal UniversityChangchun 130103China

Photo-assisted lithium-oxygen(Li-O_(2))batteries have been developed as a new system to reduce a large overpotential in the Li-O_(2)batteries.However,constructing an optimized photocatalyst is still a challenge to achieve broad light absorption and a low recombined rate of photoexcited electrons and holes.Herein,oxygen vacancy-rich molybdenum trioxide(MoO_(3-x))nanorods are employed as photocatalysts to accelerate kinetics of cathode reactions in the photo-assisted Li-O_(2)batteries.Oxygen vacancies on the MoO_(3-x)nanorods can not only increase light-harvesting capability but also improve electrochemical activity for the cathode reactions.Under illumination,the photoexcited electrons and holes are effectively separated on the MoO_(3-x)nanorods.During discharging,activated O2 is reduced to Li_(2)O_(2)by the photoexcited electrons from the MoO_(3-x)nanorods.The photoexcited holes can promote the decomposition of Li_(2)O_(2)during subsequent charging.Accordingly,the photo-assisted Li-O_(2)batteries with the MoO_(3-x)nanorods deliver an ultralow overpotential of 0.22 V,considerable rate capability,and good reversibility.We think that this work could give a reference for the exploitation and application of the photocatalysts in the photo-assisted Li-O_(2)batteries.

关键词： molybdenum trioxide(MoO_(3))nanorods oxygen vacancy photocatalyst photo-assistance lithium-oxygen(Li-O_(2))batteries

Self-assembled nanochaperones enable the disaggregation of amyloid insulin fibrils

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Science China Chemistry 2022年第2期65卷 353-362页

作者： Hui Wang Ang Li Menglin Yang Yu Zhao Linqi Shi Rujiang Ma Key Laboratory of Functional Polymer Materials of Ministry of Education Institute of Polymer ChemistryCollege of ChemistryNankai UniversityTianjin 300071China State key laboratory of Medicinal Chemical Biology Nankai UniversityTianjin 300071China

The deposition of highly ordered amyloid fibrils is recognized as a hallmark of amyloidosis diseases such as Alzheimer’s disease and Parkinson’s disease.Disaggregating the amyloid fibrils is considered as one of the effective strategies for the control and treatment of amyloidosis diseases.In this article,by simulating the function of natural molecular chaperones,co-assembled block copolymer micelles with coordination groups of nitrilotriacetic acid(NTA)and hydrophobic microdomains of poly(Nisopropylacrylamide)(PNIPAM)on the surface were used as nanochaperones(n Chaps)to disaggregate amyloid insulin fibrils.Zinc ions chelated by NTA can bind the histidine imidazole residues while the PNIPAM microdomains can interact with the exposed hydrophobic sites on the amyloid insulin fibrils,which synergistically perturb the stability of amyloid insulin fibrils,loosen their structure,and finally promote their disaggregation.A combination of characterizations with fluorescence spectroscopy,transmission electron microscopy(TEM),dynamic hight scattering(DLS),and quartz crystal microbalance(QCM)demonstrated that mature amyloid insulin fibrils were completely disaggregated after incubating with n Chaps for 90 h.This study may provide a promising strategy for the development of n Chaps for the treatment of amyloidosis diseases.

关键词： amyloid fibrils insulin nanochaperones disaggregation

N-Heterocyclic carbene-stabilized platinum nanoparticles within a porphyrinic nanocage for selective photooxidation

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Science China Chemistry 2023年第3期66卷 778-782页

作者： Yi-Shou Wang Hao Li Sha Bai Yao-Yu Wang Ying-Feng Han key laboratory of Synthetic and Natural functional Molecule of the ministry of education Xi’an Key Laboratory of Functional Supramolecular Structure and MaterialsCollege of Chemistry and Materials ScienceNorthwest UniversityXi’an 710127China

The successful construction of highly stable and active platinum nanoparticles(Pt NPs) within the confined cavity of a threedimensional porphyrinic nanocage is presented in this study. The flexible porphyrinic nanocage containing eight N-heterocyclic carbene(NHC) precursors was prepared using a metal-carbene-templated ring-closing metathesis(RCM) approach as new capping materials for the fabrication/stabilization of Pt NPs. Notably, the NHC-stabilized Pt NPs within the porphyrinic nanocage exhibited high catalytic activity for selective oxidation of 2-chloroethyl ethyl sulfide to nontoxic 2-chloroethyl ethyl sulfoxide with excellent stability and recyclability.

关键词： polycarbenes porphyrinic cage nanoparticles photocatalysis

Grain-boundary segregation and grain growth in nanocrystalline substitutional solid solution alloys

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Journal of materials Science & Technology 2024年第1期168卷 239-249页

作者： Fawei Tang Chao Hou Hao Lu Zhi Zhao Xiaoyan Song Faculty of materials and Manufacturing Key Laboratory of Advanced Functional MaterialsMinistry of Education of ChinaBeijing University of TechnologyBeijing 100124China

A model for describing solute segregation at grain boundaries has been developed for substitutional solid solution alloys,which integrates multiple factors from atomic to microstructural scales.A concept of mo-lar Gibbs free energy of segregation was introduced to evaluate the segregating capability of the solute elements in a closed system,through which the influences of grain boundary structure,grain size,ma-terial composition,and external conditions were described.Based on the evaluation of various energy forms related to solute segregation and grain growth processes,the nature of the thermal stabilization of nanograin structures by solute segregation was disclosed.A criterion for the destabilization of nanostruc-tures,which is determined by the competition of the change rates between the molar Gibbs free energy of segregation and the total energy of grain boundaries with grain size,has been proposed.This study provided guideline to achieve high-temperature stability of nanograin structures of solid solution alloys even for the weakly segregating nanocrystalline systems.

关键词： Substitutional solid solution Grain boundary segregation Thermal stabilization Solute concentration Grain size

Nanocomposites Facilitate the Removal of AβFibrils for Neuroprotection

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Chemical Research in Chinese Universities 2022年第2期38卷 522-528页

作者： CHAI Jingshan LI Qiushi ZHAO Yu LIU Yang key laboratory of functional polymer materials Ministry of EducationState Key Laboratory of Medicinal Chemical BiologyCollege of ChemistryNankai UniversityTianjin 300071P.R.China

Accumulation of β-amyloid(Aβ) fibrils in the brain is one of the main culprits in Alzheimer’s disease(AD) progression, which initiates the neuronal damage and subsequent neurodegeneration. Various anti-Aβ agents have shown the potentials to dissociate Aβ fibrils. However, these approaches can’t facilitate the removal of Aβ fibrils, resulting in a disappointing therapeutic effect. Herein, we demonstrate an integrated polymer nanocomposite(NP-GLVFF-IgG) that can dissociate Aβ fibrils into fragments and activate microglia to remove the fragments via Fc receptors-mediated phagocytosis. NP-GLVFF-IgG is constructed by an albumin/polymer hybrid nanoparticle with Gly-Leu-Val-Phe-Phe (GLVFF) peptides and Immunoglobulin G(IgG) molecules on the surface. In this design, NP-GLVFF-IgG achieves to dissociate the Aβ fibrils by the strong hydrogen-bonding interactions between Aβ fibrils and GLVFF peptides. Then, NP-GLVFF-IgG activates the microglial phagocytosis, thereby achieving an enhanced phagocytic removal of Aβ fibrils for neuroprotection. Moreover, NP-GLVFF-IgG achieves to trigger the effective removal of Aβ fibrils even under inflammatory condition that usually suppressed phagocytosis. Therefore, NP-GLVFF-IgG has great potential as a novel therapeutic platform for effective AD therapy.

关键词： Alzheimer’s disease Aβfibril Nanocomposite Hydrogen-bonding interaction Microglia

SYNTHESIS OF CdS/SiO_2/polymer TRI-LAYER FLUORESCENT NANOSPHERES WITH functional polymer SHELLS

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Chinese Journal of polymer Science 2012年第3期30卷 359-369页

作者：杨新林 key laboratory of functional polymer materials the Ministry of EducationInstitute of Polymer ChemistryNankai University

Tri-layer CdS/SiOz/polymer hybrid nanospheres were synthesized by distillation precipitation polymerization of either ethyleneglycol dimethacrylate （EGDMA） or EGDMA together with comortomers havirLg different functional groups, such as methacrylic acid, 4-vinylpyridine and 2-hydroxyethylmethacrylate, in the presence of 3-（methacryloxy）propyl trimethoxysilane （MPS）-modified CdS/SiO2 nanoparticles as seeds in acetonitrile with 2,2＇-azobisisobutyronitrile （AIBN） as initiator. In this approach, MPS-modified inorganic seeds were prepared by the modification of CdS/SiO2 nanoparticles via the self-condensation reaction between the hydroxyl groups of sinaols, in which the CdS/SiO2 nanoparticles were afforded by a reverse microemulsion technique for the synthesis of CdS core nanoparticles with the subsequent coating of silica layer. The polymer shell-layers encapsulated over the MPS-modified CdS/SiO2 inorganic seeds via the efficient capture of the monomers and oligomers from the solution with the aid of the vinyl groups incorporated by the MPS modification, in which the polymer shell-thickness and functional groups including carboxyl, pyridyl and hydroxyl, were facilely controlled by the feed of EGDMA as well as the types of comonomers used for the polymerization. These nanospheres were characterized by transmission electron microscopy （TEM）, Fourier-transform infrared spectroscopy （FT-IR）, thermogravimetric analysis （TGA）, fluorescence spectroscopy and zeta potential.

关键词： Fluorescent nanosphere Inorganic/polymer hybrid microsphere Core-shell nanoparticles Distillationprecipitation polymerization.

具有超高碱性稳定性和尺寸稳定性的聚芳烃N-甲基奎宁基阴离子交换膜

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Science China materials 2024年第3期67卷 965-973页

作者：文菊贺显颖张干兵曾梦莹钱宇黎明 Collaborative Innovation Center for Advanced Organic Chemical materials Co-constructed by the Province and ministry Ministry-of-Education Key Laboratory for the Synthesis and Application of Organic Functional MoleculesHubei Key Laboratory of Polymer MaterialsCollege of Chemistry and Chemical EngineeringHubei UniversityWuhan 430062China

阴离子交换膜水电解槽的阴离子交换膜成本低、无需铂族贵金属催化剂,有望取代高成本的质子交换膜水电解槽.然而,阴离子交换膜的尺寸稳定性差以及在高温、高浓度碱液中的稳定性差,阻碍了阴离子交换膜水电解槽的发展.最近,我们合成了一种... 详细信息

阴离子交换膜水电解槽的阴离子交换膜成本低、无需铂族贵金属催化剂,有望取代高成本的质子交换膜水电解槽.然而,阴离子交换膜的尺寸稳定性差以及在高温、高浓度碱液中的稳定性差,阻碍了阴离子交换膜水电解槽的发展.最近,我们合成了一种具有优异碱性稳定性的聚(三苯基-N-甲基奎宁基)阴离子交换膜,为了进一步提高这种阴离子交换膜的机械强度和尺寸稳定性,在本工作中,我们添加了三氟苯乙酮来制备聚(三苯基-三氟苯乙酮-N-甲基奎宁基)阴离子交换膜.这种共聚阴离子交换膜具有超高的碱性稳定性(在80℃,10 mol L^(-1)的NaOH溶液中浸泡1600小时后OH^(-)电导率和机械强度不发生衰减),优异的尺寸稳定性(30–80℃温度下,纯水中溶胀率不超过7%;10 mol L^(-1)的NaOH溶液中溶胀率不超过2%),高氢氧根电导率(80°C时达134.5 mS cm^(-1))和高机械强度(抗拉伸强度达43.2 MPa).这种阴离子交换膜和镍合金泡沫电极组装的简易水电解槽在80°C下,2.0 V和5 mol L^(-1)的KOH水电解质中具有1780 mA cm^(-2)的优异电流密度,并且具有高耐久性.

关键词： anion exchange membrane N-methylquinuclidinium alkaline stability dimensional stability water electrolyser

PREPARATION OF POLYALKYLCYANOACRYLATE NANOPARTICLES WITH VARIOUS MORPHOLOGIES

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Chinese Journal of polymer Science 2011年第3期29卷 336-341页

作者：李贺先 key laboratory of functional polymer materials Ministry of EducationInstitute of Polymer Chemistry Nankai University

The effects of various reaction conditions on the preparation of polyalkylcyanoacrylate （PACA） nanoparticles are studied. The PACA nanoparticles with different crosslinking degrees and morphology are prepared. Addition of crosslinkers can not only adjust the particle size, but also change the morphology of PACA nanoparticles. Moreover, the loose network structure of the PACA nanoparticles with ＂core/shell-like＂ morloholozv is investizated by AFM and TEM in detail.

关键词： Nanoparticles Biodegradability PACA Network structure Drug carriers.

Preparation of porous polyamide 6(PA6)membrane with copper oxide(CuO)nanoparticles selectively localized at the wall of the pores via reactive extrusion

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Nano materials Science 2022年第2期4卷 169-177页

作者： Tianqi Liang Jie Liu Zhaoyang Wei Dean Shi Hubei Collaborative Innovation Center for Advanced Organic Chemical materials Ministry-of-Education Key Laboratory for the Green Preparation and Application of Functional MaterialsHubei Key Laboratory of Polymer MaterialsSchool of Materials Science and EngineeringHubei UniversityWuhan430062PR China

In this study,CuO nanoparticles are pre-modified with styrene-maleic anhydride copolymers(SMAs)of different molecular weights and MAH contents.Then the pre-modified CuO nanoparticles(CuO-SMAs)are added to the PA6/SEBS(Styrene Ethylene Butylene Styrene copolymer)(40/60 wt/wt)polymer blends with a co-continuous morphology.When SMA3(MAH=8 wt%,M_(n)=250000 g/mol)is used to modify CuO nanoparticles,and the grafting degree of SMA3 on the surface of CuO reaches 2.74 wt%,90.71%of the added mCuO-SMA3 nanoparticles can be located at the interface of PA6 and SEBS.A porous PA6 membrane with CuO nanoparticles located at the pore walls can be obtained after the SEBS phase is etched with xylene.The catalytic reaction velocity constant(k)for the reduction of p-nitrophenol in NaBH_(4)solutions with the PA6/mCuO-SMA3 porous membrane can reach 1.0040 min^(-1).This work provides a feasible and straightforward method for the preparation of porous polymer membranes with functional nanoparticles located at the wall of the pores.

关键词： Co-continuous CuO nanoparticles Selective distribution Porous PA6 membrane Catalytic performance