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highly efficient catalyzed by imidazolium-based dual-sulfonic acid functionalized ionic liquids for liquid phase Beckmann rearrangement:experiments and COSMO-RS calculations

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Green Chemical Engineering 2024年第1期5卷 108-118页

作者： Xin Guo Zhiyuan Wang Ye Yang Jiahui Zhang Yanduo Liu Zhiyuan Mu Siqi Jiang Chunxiao Ren Dan Lv Yufeng hu Zhichang Liu State Key Laboratory of heavy Oil Processing and high Pressure Fluid Phase Behavior&Property Research Laboratory China University of PetroleumBeijing102249China School of Chemistry and Materials Science University of Science and Technology of ChinaHefei230026China School of Light Industry and Engineering South China University of TechnologyGuangzhou510641China

A production technique with the high yield and environmentally friendly process need be developed forε-Caprolactam(CPL)in the chemical *** technology is highly desired to design and synthesize high--performance catalysts for liquid phase Beckmann rearrangement of cyclohexanone oxime(ChO)to *** this work,3-methyl-1-(propyl-4-sulfonyl)imidazolium methanesulfonate([PhSO_(3)MIM][MSA])with highly efficient and excellent yield is synthesized *** the optimum molar ratio of ZnCl_(2)over[PhSO_(3)MIM][MSA]was 0.02,it exhibits the high selectivity(94%)of CPL at 90℃for 1 ***,Fourier-transform infrared(FT-IR)investigations show that the functional Br∅nsted-Lewis acidic types of ionic liquids(ILs)are formed by the uniformly distributed ZnCl_(2)and[PhSO_(3)MIM][MSA].In addition,the hydrogen bond(h-bond)is formed between ChO and *** ten reaction cycles,no significant structure changes are observed in the recovered[PhSO_(3)MIM][MSA]-ZnCl_(2).The solubilities of ILs are predicted by using COSMO-RS model,the results show that[PhSO_(3)MIM][MSA]is a promising candidate for the liquid phase Beckmann rearrangement of ChO into ***,a theoretical model of the h-bond interactions between ILs and ChO is further confirmed to support the advance of reaction mechanism.A feasible way is provided for the CPL production technique in the liquid phase Beckmann rearrangement reaction.

关键词： Liquid phase Beckmann rearrangement Imidazolium-based ionic liquids COSMO-RS calculations h-bond

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Supporting-electrolyte-free electrochemical[2+2+1]annulation of benzo[d]isothiazole 1,1-dioxides,N-arylglycines and paraformaldehyde

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Chinese Chemical Letters 2024年第6期35卷 327-330页

作者： hai-Yang Song Jun Jiang Yu-hang Song Min-hang Zhou Chao Wu Xiang Chen Wei-Min he School of Chemistry and Chemical Engineering University of South ChinaHengyang 421001China

The h-bond promoted electrochemical[2+2+1]annulation of benzo[d]isothiazole 1,1-dioxides,Narylglycines and paraformaldehyde for the synthesis of various benzo[d]imidazo[1,5-b]isothiazole 5,5-dioxide derivatives under ... 详细信息

关键词： h-bond N-Arylglycines Paraformaldehyde Organic electro-synthesis Electrolyte-free

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POCl_3-mediated h-bonding-directed one-pot synthesis of macrocyclic pentamers,strained hexamers and highly strained heptamers

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Science China Chemistry 2012年第1期55卷 55-63页

作者： LIU Ying QIN Bo ZENG huaQiang Department of Chemistry National University of Singapore Singapore 117543 Singapore College of Chemistry and Chemical Engineering Chongqing University Chongqing 400030 China

Previously we have shown that POCl3-mediated h-bonding-directed one-pot macrocyclization allows for the highly selective preparation of five-residue macrocycles as the predominant product with low yields of hexamers and an undetectable occurrence of both tetramers and *** the interiorly arrayed methyl groups with ethyl groups in these 4-7 residue macrocycles alters the relative stability order among ***,ethoxy-substituted six-residue macrocycle,rather than pentamer,turns out to be computationally the most stable,suggesting that ethoxy-containing hexamer possibly can be formed as the major product under suitable *** have investigated this possibility by varying reaction temperatures and concentrations,invariably affording pentamer as the major macrocycle with strained circular hexamers and highly strained circular heptamers produced in substantial *** discrepancy can be reasonably explained on the basis of bimolecular reactions between two oligomers higher than monomers via kinetic *** this scenario,the acyclic pentamer is kinetically "trapped" to undergo an intramolecular cyclization to yield circular pentamer,rather than to produce acyclic *** a result,acyclic hexamer precursor is generated largely from sterically demanding bimolecular reactions between a dimer and a tetramer,or between two trimers that are kinetically slower than the pentamer-producing chain-growth *** additionally found that one-pot macrocyclization proceeds to the largest extent at 40 ℃,an intriguing finding that highlights the low reactivities of acid chloride and amine groups in these h-bond-enforced acyclic oligomeric intermediates.

关键词： supramolecular chemistry foldamer h-bond macrocycles one-pot synthesis POCl3

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Self-healed microcracks in polymer bonded explosives via thermoreversible covalent bond and hydrogen actions

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Defence Technology（防务技术） 2023年第10期28卷 183-194页

作者： Yu-bin Li Xu Zhao Ya-jun Luo Zhi-jian Yang Li-ping Pan Cheng-cheng Zeng Cong-mei Lin Xue Zheng Institute of Chemical Materials China Academy of Engineering PhysicsMianyang621900China

Polymeric materials used for the polymer bonded explosive(PBX)or other energetic composite materials(ECMs)that simultaneously possess excellent mechanical properties and high self-healing ability,convenient healing,and facile fabrication are always a huge ***,self-healing linear polyurethane elastomers(PTMEG2000-IPDI-DAPU,denoted as 2I-DAPU)with high healing efficiency and mechanical properties were facilely fabricated by constructing reversible covalent bonds and dynamic hard domains into polymer ***,a TATB-based PBX using as-prepared 2I-DAPU polymer as the binder was constructed,disclosing an excellent self-healing property to heal cracks generated during fabrication,transportation and *** damage healing manner of such a PBX sample was investigated by means of prefabricated damage through mechanical load,heal treatment via heating at high temperature,and CT-scanning the inner structure and mechanical property characterization via Brazilian *** self-healing mechanism of internal damage in PBX was preliminarily *** propose that this 2I-DAPU binder with Diels-Alder bonds could generate plentiful active surface groups resulting from damage and drive self-healing at fitting temperature and increase the slightly packed hard phase via incorporating a small amount of hydrogen *** work may offer a novel strategy for improving mechanical property and healing ability in the field of self-healing material which could help expand its applications with enhanced versatility in mechanical-enhanced functional materials.

关键词： Polymer bonded explosives Self-healing polymers Diels-alder(DA)bonds h-bond

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FTIR STUDIES ON ThE MODEL POLYUREThANE hARD SEGMENTS BASED ON A NEW WATERBORNE ChAIN EXTENDER DIMEThYLOL BUTANOIC ACID (DMBA)

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Chinese Journal of Polymer Science 2004年第3期22卷 225-230页

作者：马德柱 Department of Polymer Science and Engineering University of Science and Technology of China Hefei 230026 China

Three model polyurethane hard segments based on dimethylol butanoic acid (DMBA) and 1,6-hexane diisocyanate (hDI), toluene diisocyanate (TDI) and 4,4'-diphenylmethane diisocyanate (MDI) were prepared by the solution method. Fourier Infrared (FTIR) spectroscopy was employed to study the h-bonds in these model polyurethanes. The model polyurethane hard segment prepared from hDI and 1,4-butanodiol (BDO) was used for comparison. It was found that the incorporation of the pendent carboxyl through DMBA into the model hard segments weakens the original Nh…O = C h-bond but gives more h-bond patterns based on the two h-bond donors, urethane Nh and carboxylic Oh. The carboxylic dimer is one of the main h-bond types and is stronger than another main h-bond type Nh…O=C. In addition, the h-bond in aromatic model hard segments is stronger than that of aliphatic hard segments. The appearance of the free C=O and the fact that almost all N—h is h-bonded suggest that there possibly exist either the third h-bond acceptor or the h-bond formed by one acceptor with two donors.

关键词： Model hard segment h-bond Polyurethane with carboxyl FTIR spectroscopy

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Oh…O Out-of-Plane Bending Band [γ(Oh)] and Its Overtone Band of Dimethylol Propionic Acid(DMPA)

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Chemical Research in Chinese Universities 2004年第1期20卷 99-102页

作者： RENZhi-yong MAJian-Ming WUhai-ping MADe-zhu DepartmentofPolymerScienceandEngineering UniversityofScienceandTechnologyofChinaHefei230026P.R.China CollegeofChemistryandChemicalEngineering AnhuiUniversityHefei230039P.R.China

In the present paper are reported the Oh…O out-of-plane bending band[γ(Oh)] between 900—950 cm -1 of dimethylol propionic acid(DMPA), its dependence upon temperature and its overtone band investigated via FTIR spectroscopy. It has been found based on the crystal structure that the band [γ(Oh)] may not certainly be the characteristic band of carboxylic dimers, it can also result from another h-bond formed between carboxylic carbonyl and the primary hydroxyl. In addition, the band [γ(Oh)] is very sensitive to temperature change but its overtone band can only appear at a low temperature.

关键词： h-bond Out-of-plane bending band Overtone

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Theoretical study of the N—h···O red-shifted andblue-shifted hydrogen bonds

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Science China Chemistry 2007年第1期50卷 32-40页

作者： YANG Yong ZhANG WeiJun PEI ShiXin ShAO Jie hUANG Wei GAO XiaoMing Laboratory of Environmental Spectroscopy Anhui Institute of Optics and Fine MechanicsChinese Academy of SciencesHefei 230031China

Theoretical calculations are performed to study the nature of the hydrogen bonds in complexes hChO···hNO, hCOOh···hNO, hChO···Nh3, hCOOh···Nh3, hChO···Nh2F and hCOOh···Nh2F. The geomet- ric structures and vibrational frequencies of these six complexes at the MP2/6-31+G(d,p), MP2/6-311++G(d,p), B3LYP/6-31+G(d,p) and B3LYP/6-311++G(d,p) levels are calculated by standard and counterpoise-corrected methods, respectively. The results indicate that in complexes hChO···hNO and hCOOh···hNO the N—h bond is strongly contracted and N—h···O blue-shifted hydrogen bonds are observed. While in complexes hChO···Nh3, hCOOh···Nh3, hChO···Nh2F and hCOOh···Nh2F, the N—h bond is elongated and N—h···O red-shifted hydrogen bonds are found. From the natural bond orbital analysis it can be seen that the X—h bond length in the X—h···Y hydrogen bond is controlled by a balance of four main factors in the opposite directions: hyperconjugation, electron density redistribu- tion, rehybridization and structural reorganization. Among them hyperconjugation has the effect of elongating the X—h bond, and the other three factors belong to the bond shortening effects. In complexes hChO···hNO and hCOOh···hNO, the shortening effects dominate which lead to the blue shift of the N—h stretching frequencies. In complexes hChO···Nh3, hCOOh···Nh3, hChO···Nh2F and hCOOh···Nh2F where elongating effects are dominant, the N—h···O hydrogen bonds are red-shifted.

关键词： red-shifted h-bond blue-shifted h-bond AIM topological analysis NBO analysis

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A novel Ah-D-A-type phase junction material to improve photovoltaic performance and device stability in fullerene OSCs

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Chinese Chemical Letters 2020年第9期31卷 2452-2458页

作者： Lin Shao Fei Tong Mengbing Zhu hao Xia Wenhong Peng hua Tan Bin Zhang Yu Liu Weiguo Zhu College of Chemistry Xiangtan UniversityXiangtan 411105China School of Materials Science and Engineering Jiangsu Collaborative Innovation Center of Photovoltaic Science and EngineeringJiangsu Engineering Laboratory of Light-Electricity-Heat Energy-Converting Materials and ApplicationsNational Experimental Demonstration Center for Materials Science and EngineeringChangzhou UniversityChangzhou 213164China

In order to boost power conversion efficiency(PCE) and operation stability of organic solar cells(OSCs),we propose a new idea of phase junction materials(PJMs) used as a photoactive layer component to improve device performance and *** this purpose,a novel PJM of h-TRC8 based on rhodanine unit was designed with a conjugated Ah-D-A ***,Ah is a hydrogen-donating electron acceptor unit,D-A is an electron donor-acceptor *** is found that h-TRC8 has a good carriertransporting ability,as well as definite hydrogen-bond and D-A interaction with donor/acceptor *** h-TRC8 is added into the PBDB-T/PC60BM blend film with 1.0 vol% DIO(1,8-diiodooctane),the resulting blend film exhibited an enhanced absorption and improved *** intermolecular hydrogen bond between h-TRC8 and PBDB-T plays an important role for them,which is confirmed via FT-IR spectra and 2D 1h *** a result,the PBDB-T/PC60BM-based devices with 1.25 wt%h-TRC8 and 1.0 vol% DIO exhibit a significantly improved PCE of 8.06%,which is increased by 20.6% in comparison to that in the binary devices with 1.0 vol% DIO only(PCE=6.68%).Furthermore,the device stability is significantly enhanced with only 43% PCE roll-off at 150℃ for 120 *** work indicates that Ah-D-A-type PJMs are promising photovoltaic materials used as photoactive-layer components to achieve high-performance fullerene OSCs with high device stability.

关键词： Phase junction material A_h-D-A h-bond h-TRC8 Performance and stability

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Novel four-hydrogen-bond assembled oligoamide dimer with pyrazoline moieties and its photoluminescent properties

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Chinese Chemical Letters 2009年第12期20卷 1419-1422页

作者： Guang Dong Lei Ming Li De Min Qiu hui Liu Yan huang Zhi Yun Lu Department of Chemistry and Life Science Neijiang Normal College Neijiang 641112 China College of Chemistry Sichnan University Chengdu 610064 China

In this paper, the synthesis and characterization of a triarylpyrazoline modified four-h-bonded molecular duplex are described. Its molecular structure has been confirmed by ^1h NMR and ESI-MS. The duplex emits strong pure blue light peaking at 448 and 452 nm under UV photoexcitation in solution and solid state, respectively, and its relative photoluminescence quantum efficiency in solution is determined as 0.778 using quinine sulfate as reference. In concentration of 〉40 mmol/L, the duplex can gelate DMSO, and the organogel formed shows good pure blue photoluminescence too. This novel duplex, for its well-defined structure and efficient photoluminescence property, is a prospective candidate for pure blue electroluminescent emitter.

关键词： Self-assembly h-bond Pyrazoline Photoluminescence Organogel

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Design and Synthesis of a highly Stable Six-hydrogen-bonded Serfassembly Yellowish Green Electroluminescent Molecular Duplex

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Chinese Chemical Letters 2005年第9期16卷 1185-1188页

作者： Guang Dong LEI Yi YI Zhi Yun LU Ming Gui XIE College of Chemistry Sichuan Universtiy Chengdu 610064 Department of Chemistry and Life Science Neijiang Normal College Neijiang 641112

This paper describes the design, synthesis and characterization of a hydrogen-bonded molecular duplex with 1,8-naphthalimide fluorescent pendants. The two oligoamide molecular strands, with complementary hydrogen bond sequences of DDADAA and AADADD, can form an ultra stable self-assembly duplex. Its molecular structure was confu-med by ^1h NMR and ESI-MS, and its photoluminescence properties were determined. The resulting duplex exhibited a dramatically enhanced photoluminescence （PL） quantum efficiency of 63.7% compared to the corresponding 1,8-naphthalimide segment （32.4%）, suggesting that the formation of the duplex with larger molecular weight could successfully inhibit the quenching of the fluorescent pendant. This novel duplex is a prospective candidate for new electroluminescent emitter.

关键词： Selfassembly h-bond 1 8-naphthalimide photoluminescence electroluminescence

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