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hydrogen-bond-assisted transition-metal-free catalytic transformation of amides to esters

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Science China Chemistry 2021年第1期64卷 66-71页

作者： Changyu Huang Jinpeng Li Jiaquan Wang Qingshu Zheng Zhenhua Li Tao Tu Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Department of ChemistryFudan UniversityShanghai 200438China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China Green Catalysis Center and College of Chemistry Zhengzhou UniversityZhengzhou 450001China

The amide C-N cleavage has drawn a broad interest in synthetic chemistry,biological process and pharmaceutical ***-metal,luxury ligand or excess base were always vital to the ***,we developed a transition-metalfree hydrogen-bond-assisted esterification of amides with only catalytic amount of *** proposed crucial role of hydrogen bonding for assisting esterification was control experiments,density functional theory(DFT)calculations and kinetic *** broad substrate scopes and excellent functional groups tolerance,this base-catalyzed protocol complements the conventional transition-metal-catalyzed esterification of amides and provides a new pathway to catalytic cleavage of amide C–N bonds for organic synthesis and pharmaceutical industry.

关键词： amides C–N bond cleavage esterification hydrogen bonding transition-metal-free catalysis

Hyperbranched magnetic polymer:highly efficient removal of Cr(Ⅵ)and application in electroplating wastewater

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Frontiers of Chemical Science and Engineering 2023年第10期17卷 1568-1580页

作者： Nan Sun Qing Wu Lifang Jin Zichen Zhu Jianhui Sun Shuying Dong Haijiao Xie Chunyan Zhang Yanrui Cui Key Laboratory for Yellow River and Huai River Water Environmental and Pollution Control Ministry of Educationand Henan Key Laboratory for Environmental Pollution ControlSchool of EnvironmentHenan Normal UniversityXinxiang 453007China

By using a two-step hydrothermal method and trithiocyanuric acid(TTCA),2,4,6-trihydrazino-1,3,5-triazine(THT),and Fe_(3)O_(4)as raw materials,a spherical magnetic adsorbent polymer(TTCA/THT@Fe_(3)O_(4))was synthesized to achieve the efficient removal of Cr(VI)from *** optimal adsorption conditions,the maximum adsorption capacity of TTCA/THT@Fe_(3)O_(4)for Cr(VI)can reach 1340 mg∙g‒***,the removal efficiency can approach 98.9%,even at the lower concentration of 20 mg∙L^(‒1)Cr(VI).For actual wastewater containing Cr(VI),the Cr(VI)concentration was reduced from 25.8 to 0.4 mg∙L^(‒1),a remarkable 20%lower than the current industry discharge standard value.A mechanism for the high adsorption performance of Cr(VI)on TTCA/THT@Fe_(3)O_(4)was investigated using Fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy,and density functional *** can be plausibly attributed to the formation of Cr/N and Cr/S coordination ***,surface electrostatic adsorption,reduction effects,and the spherical polymer structure increase the contact area with Cr(VI),maximizing *** synergistic effect of adsorption and reduction enhances the adsorption performance of TTCA/THT@Fe_(3)O_(4)for Cr(VI)and total chromium in *** resultant polymer has a simple preparation process,excellent adsorption performance,easy magnetic separation,and promising application for actual wastewater.

关键词： magnetic polymer chromium removal hydrogen bonding recyclability actual wastewater

Tailoring the Self-assembly of Melamine on Au（111） via Doping with Cu Atoms

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Chinese Journal of Chemical Physics 2017年第4期30卷 443-449,I0002页

作者：石何霞王文元李喆王利邵翔中国科学技术大学化学物理系中国科学院城市污染物转化重点实验室中国科学技术大学量子信息与量子科技前沿协同创新中心合肥230026

The doping effect of Cu on the self-assembly film of melamine on an Au（111） surface has been investigated with scanning tunneling microscopy （STM）. The evaporated Cu adatoms occupy the positions underneath the amino groups and change the hydrogen bonding pat- tern between the melamine molecules. Accordingly, the self-assembly structure has changed stepwise from a well-defined honeycomb into a track-like and then a triangular structure depending on the amount of Cu adatoms. The interaction between Cu adatom and melamine is moderate thus the Cu adatoms can be released upon mild heating to around 100 ℃. These findings are different from previous observations of either the coordination assembly or the physically trapped metal adatoms.

关键词： Melamine Self-assembly Scanning tunneling microscopy Cu adatoms hydrogen bonding

Improved crystallinity and self-healing effects in perovskite solar cells via functional incorporation of polyvinylpyrrolidone

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Journal of Energy Chemistry 2022年第5期31卷 12-18页

作者： Yunjuan Niu Dingchao He Zhengguo Zhang Jun Zhu Tulloch Gavin Polycarpos Falaras Linhua Hu Key Laboratory of Photovoltaic and Energy Conservation Materials Institute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031AnhuiChina University of Science and Technology of China Hefei 230026AnhuiChina School of Chemistry and Chemical Engineering North Minzu UniversityYinchuan 750021NingxiaChina Special Display and Imaging Technology Innovation Center of Anhui Province Anhui Province Key Laboratory of Measuring Theory and Precision InstrumentAcademy of Opto-Electric TechnologyHefei University of TechnologyHefei 230009AnhuiChina National Center for Scientific Research‘‘Demokritos” Institute of Nanoscience and Nanotechnology(INN)15310 Agia Paraskevi AttikisAthensGreece Greatcell Energy 280 Byrnes RdWagga WaggaNSW 2650Australia

Air moisture is the key issue for perovskites which invades the films and accelerates the damage of devices. Here, polyvinylpyrrolidone(PVP) is introduced to the methylammonium lead iodide(MAPbI_(3)) perovskite precursor to control crystal growth and endow the devices with self-healing ability in a moisture environment. The strong C=O...ΗAΝ hydrogen bonding interactions between PVP and MAPbI_(3) was confirmed by nuclear magnetic resonance measurements. By introducing hydrogen bonding in the MAPbI_(3)-based PSCs, we form a compact perovskite film of excellent electronic quality with a power conversion efficiency(PCE) of up to 20.32%. Furthermore, the O...ΗAΝ hydrogen bonding interactions at the grain boundaries suppress the decomposition of methylammonium cations and improve the recyclable dissolution–recrystallization of perovskite. As a result, the MAPbI_(3)-PVP based cells exhibited striking moisture stability and self-healing behavior, with negligible decay in efficiency after 500 h of operation in high humidity(65% ± 5% relative humidity) and rapid recovering ability after their removal from the humid environment.

关键词： Perovskite solar cells Self-healing Carbonyl groups hydrogen bonding

Ternary deep eutectic solvents catalyzed D-glucosamine self-condensation to deoxyfructosazine: NMR study

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Green Energy & Environment 2021年第2期6卷 261-270页

作者： Pengfei Liu Christian Marcus Pedersen Jiaojiao Zhang Rui Liu Zhenzhou Zhang Xianglin Hou Yingxiong Wang Shanxi Engineering Research Center of Biorefinery Instiute of Coal ChemistryChinese Academy of Sciences27 South Taoyucn Road Taiyun030001China Center of Materials Science and Optoeletronics Engineering University of Chinese Academy of SciencesBejing100049China Department of Chemistny University of CopenhagenUniversitetsparken 5DK-2100 CopenhagenDenmark School of Chemical Engineering Zhengzhou University Zhengzhou450001China

Ternary deep eutectic solvents(TDESs) comprising choline chloride(Ch Cl), glycerol and L-arginine were synthesized as catalysts and solvents for the conversion of D-glucosamine(GlcNH_(2)) into deoxyfructosazine(DOF). The interactions between these three components in the prepared TDESs were studied by ^(1)H-,^(35)Cl-NMR spectra and ^(1)H diffusion-ordered spectroscopy(DOSY) measurements. The chemical shift changes of active hydrogen in the ^(1)H-NMR spectra of TDES system and widening of signals in the^(35)Cl-NMR spectra confirmed the hydrogen bonding interaction between the components, which was further supported by the decrease of diffusion coefficients(D) of the TDES components according to ^(1)H DOSY measurements. The influences of reaction temperature and L-arginine content in the TDESs on the yield of DOF were also studied. The experimental results have shown that when the molar ratio of Ch Cl, glycerol, and L-arginine was 1:2:0.1, DOF was the major product with a yield of 22.6% at 90℃ for 120 min. The chemical shift titration indicated that the carboxyl group of L-arginine in the TDES is the catalytical active site, so the mechanism of the catalytic reaction between Glc NH_(2) and the TDES was proposed. Moreover, a reaction intermediate, dihydrofructosazine, was identified in the self-condensation reaction of Glc NH_(2) by an in situ ^(1)H NMR technique.

关键词： Ternary deep eutectic solvents hydrogen bonding NMR D-glucosamine Deoxyfructosazine

Rules essential for water molecular undercoordination

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Chinese Physics B 2020年第8期29卷 33-47页

作者： Chang Q Sun School of EEE Nanyang Technological UniversitySingapore 639798

A sequential of concepts developed in the last decade has enabled a resolution to multiple anomalies of water ice and its low-dimensionality,*** concepts include the coupled hydrogen bond(O:H–O)oscillator pair,segmental specific heat,three-body coupling potentials,quasisolidity,and *** anomalies include ice buoyancy,ice slipperiness,water skin toughness,supercooling and superheating at the nanoscale,*** shows consistently that molecular undercoordination shortens the H–O bond and stiffens its phonon while undercoordination does the O:H nonbond contrastingly associated with strong lone pair“:”polarization,which endows the low-dimensional water ice with *** supersolid phase is hydrophobic,less dense,viscoelastic,thermally more diffusive,and stable,having longer electron and phonon *** equal number of lone pairs and protons reserves the configuration and orientation of the coupled O:H–O bonds and restricts molecular rotation and proton hopping,which entitles water the simplest,ordered,tetrahedrally-coordinated,fluctuating molecular crystal covered with a supersolid *** O:H–O segmental cooperativity and specific-heat disparity form the soul dictate the extraordinary adaptivity,reactivity,recoverability,and sensitivity of water ice when subjecting to physical *** is recommended that the premise of“hydrogen bonding and electronic dynamics”would deepen the insight into the core physics and chemistry of water ice.

关键词： hydrogen bonding molecular crystals structural transitions in nanoscale materials liquid-liquid transitions

Nano-/Micro-confined Water in Graphene Hydrogel as Superadsorbents for Water Purification

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Nano-Micro Letters 2020年第1期12卷 13-26页

作者： Yiran Sun Fei Yu Cong Li Xiaohu Dai Jie Ma State Key Laboratory of Pollution Control and Resource Reuse College of Environmental Science and EngineeringTongji University1239 Siping RoadShanghai 200092People’s Republic of China College of Marine Ecology and Environment Shanghai Ocean UniversityShanghai 201306People’s Republic of China Department of Chemical and Biomolecular Engineering The University of AkronAkronOH 44325USA Research Center for Environmental Functional Materials College of Environmental Science and EngineeringTongji University1239 Siping RoadShanghai 200092People’s Republic of China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092People’s Republic of China

Confined water has been proven to be of great importance due to its pervasiveness and contribution to life and many fields of scientific ***,the control and characterization of confined water are a ***,a confined space is constructed by flexibly changing the pH of a graphene oxide dispersion under the self-assembly process of a graphene hydrogel(GH),and the confined space is adjusted with variation from 10.04 to 3.52 *** water content in GH increases when the pore diameter of the confined space decreases;the corresponding adsorption capacity increases from 243.04 to 442.91 mg g−***,attenuated total reflectance Fourier transform infrared spectroscopy and Raman spectroscopy are utilized to analyze the hydrogen bonding structure qualitatively and quantitatively,and correlation analysis reveals that the improvement in the adsorption capacity is caused by incomplete hydrogen bonding in the confined ***,confined water is assembled into four typical porous commercial adsorbents,and a remarkable enhancement of the adsorption capacity is *** research demonstrates the application potential for the extraordinary properties of confined water and has implications for the development of highly effective confined water-modified adsorbents.

关键词： Confined water Graphene hydrogel hydrogen bonding Adsorption Antibiotic

Regulating photothermal properties of near-infrared croconaine dyes by supramolecular assembly

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Nano Research 2024年第9期17卷 8560-8570页

作者： Yangge Ren Yue Lu Juanjuan Gao Yi Ding Bo Zhu Xinyu Hou Lin Jia Department of Polymer Materials School of Materials Science and EngineeringShanghai UniversityShanghai 200444China Department of Electronic Information Materials School of Materials Science and EngineeringShanghai UniversityShanghai 200444China

The photochemical and photophysical properties of near-infrared(NIR)dyes are significantly influenced by their aggregation state and mesoscopic ***,beyond chemical synthesis,the regulation mechanisms for the properties of NIR dyes,particularly with respect to photothermal properties of the aggregates,are not yet fully ***,we investigate the photothermal behaviors of croconaine-based(CroA)NIR dyes containing dipeptide or amino acids *** introduction of hydrogen bonding promotesπ-πstacking of croconaine center,which can efficiently regulate aggregation states and assembly structures in *** laser irradiation,CroA aggregates undergo aggregation-dissociation transition,the in-situ monomer generation process regulates two parameters of photothermal performance:heating rates and plateau photothermal *** study reveals the regulation effect of non-covalent bonding interactions on CroA aggregates,highlighting supramolecular assembly strategy not only facilitates to construct of photothermal nanomaterials with well-defined structures,but also provides an alternative and effective method for regulating photothermal performance of NIR dyes.

关键词： croconaine dye hydrogen bonding photothermal performance supramolecular assembly chirality

Highly catalytic metal–organic framework coating enabled by liquid superwetting and confinement

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Nano Research 2023年第5期16卷 7716-7723页

作者： Bo Yi Yan-Lung Wong Kedi Li Changshun Hou Tengrui Ma Zhengtao Xu Xi Yao Department of Biomedical Sciences City University of Hong KongHong Kong 999077China Department of Chemistry City University of Hong KongHong Kong 999077China Institute of Materials Research and Engineering Agency for ScienceTechnology and Research(A*STAR)Singapore 138634Singapore City University of Hong Kong Shenzhen Research Institute Shenzhen 518057China

In this work,we report that high catalytic performance of metal–organic frameworks(MOFs)can be obtained through a synergistic effect of postsynthetic modification of MOF nanoparticles and liquid superwetting and confinement in the MOF ***,2-ureido-4[1H]pyrimidinone(UPy)functionalized polysiloxanes were covalently appended onto the UiO-66 nanoparticles via a postsynthetic approach,which were further anchored onto different porous films through multivalent hydrogen bonding of the UPy *** hydrophobic MOF coating can preserve the porosity of the solid substrates,enable rapid liquid superwetting and confinement within the porous *** the Knoevenagel condensation as a modeled system,robust and highly catalytic performances of the MOF coating were observed on a range of aldehyde ***-scale production of chromene,a pharmaceutical which is typically synthesized via expensive catalysis,was successfully demonstrated on the MOF coating with high yielding rates,demonstrating the great potential of the MOF coating in pharmaceutical synthesis.

关键词： metal–organic framework postsynthetic modification hydrogen bonding superwetting liquid confinement