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Theoretical design of new bridge-ring insensitive high energy compounds by selected normal diels-alder reactions between NH_(2)-substituted oxazoles and NO_(2)/NF_(2)/NHNO_(2)-substituted ethylenes/acetylenes

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Defence Technology（防务技术） 2021年第5期17卷 1731-1739页

作者： Qiong Wu Qin-nan Hu Ming-quan Li Ze-wu Zhang Wei-hua Zhu Jiangsu Key Laboratory of Advanced Structural Materials and Application Technology School of Materials Science and EngineeringNanjing Institute of Technology1 Hongjing RoadNanjing211167China Institute for Computation in Molecular and Materials Science and Department of Chemistry Nanjing University of Science and TechnologyNanjing210094China

In this work,NH_(2)-substituted oxazoles and NO_(2)/NF_(2)/NHNO_(2)-substituted ethylenes/acetylenes were designed and used as dienes and dienophiles,respectively,in order to develop new bridge-ring insensitive high energy compounds through the diels-alder reaction between them.The reaction type,reaction feasibility and performance of reaction products were investigated in detail theoretically.The results showed that dienes most possibly react with dienophiles through the HOMO-diene controlled normal diels-alder reaction at relatively low energy barrier.Tetranitroethylene could react with the designed dienes much more easily than other dienophiles,and was employed to further design 29 new bridge-ring energetic compounds.Due to high heat of formation,density and oxygen balance,all designed bridge-ring energetic compounds have outstanding detonation performance,16 of them have higher energy than HMX(1,3,5,7-tetranitro-1,3,5,7-tetrazocine)and 2 others even possess comparative energy with the representative of high energy compounds CL-20(2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane).The predicted average h50 value of these bridge-ring energetic compounds is 83 cm,showing their low impact sensitivity.The NH2 groups could obviously impel the proceeding of diels-alder reactions,but would slightly decrease the energy and sensitivity performance.In all,the new designed bridge-ring compounds have both high energy and low sensitivity,and may be produced through diels-alder reactions at relatively low energy barrier.This paper may be helpful for the theoretical design and experiment synthesis of new advanced insensitive high energy compounds.

关键词： diels-alder Energetic compounds Oxazole High energy Insensitive

Radical Cation diels-alder Reactions of Non-Conjugated Alkenes as Dienophiles by Electrocatalysis

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Chinese Journal of Chemistry 2019年第6期37卷 561-564页

作者： Atsushi Ozaki Yusuke Yamaguchi Yohei Okada Kazuhiro Chiba Department of Applied Biological Science Tokyo University of Agriculture and Technology3-5-8 Saiwai-choFuchuTokyo 183-8509Japan Department of Chemical Engineering Tokyo University of Agriculture and Technology2-24-16 Naka-choKoganeiTokyo 184-8588Japan

Radical cation diels-alder reactions provide a powerful method for the construction of six-membered ring systems between both electron-rich dienes and dienophiles. However, the most recent examples of this class have been limited to β-methylstyrenes as dienophiles;the use of non-conjugated alkenes remains challenging. The present study describes the serendipitous development of novel radical cation diels-alder reactions by electrocatalysis that use non-conjugated alkenes as dienophiles. The key to successful transformation involves highly substituted cyclohexenyl radical cations that are stable enough to be reduced by intermolecular single electron transfer.

关键词： radical cation diels-alder reaction non-conjugated alkene electrochemistry single electron transfer

Improved “cure on demand” of aromatic bismaleimide with thiol triggered by retro-diels-alder reaction

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Frontiers of Chemical Science and Engineering 2021年第2期15卷 330-339页

作者： Vincent Froidevaux Melanie Decostanzi Abdelatif Manseri Sylvain Caillol Bernard Boutevin Remi Auvergne Institut Charles Gerhardt Montpellier UMR 5253-CNRSUniversitede MontpellierENSCM34296 Montpellier Cedex 5France

This study focuses on the synthesis of new liquid aromatic bismaleimide monomers in order to improve self-curing on demand(SCOD)systems previously based on aliphatic bismaleimides.These SCOD systems are based on diels-alder(DA)/retro-DA reactions.The syntheses of new different aromatic bismaleimides with ester and amide bonds are presented.These maleimides have been protected using DA reaction and characterized by 1H NMR analysis to determine protection rate and diastereomer ratios.The retro-DA reactions of both aromatic and aliphatic DA adducts in presence of thiol molecules were studied.Kinetic analysis was monitored by 1H NMR and compared to model study.Finally,both aromatic and aliphatic bismaleimides-based polymers were synthesized with 2-mercaptoethyl ether and thermal properties of polymers were compared.The glass transition temperature values ranged from–20°C to 14°C and very good thermal stabilities were observed(up to 300°C).

关键词： thiol-ene polymerization self-curing on demand thia-michael addition diels-alder maleimide

Theoretical Study of Kinetics and Thermodynamics of Hetero diels-alder Reaction of Thiazole and Isothiazol with Thiophene-2,5-dione

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Chinese Journal of Structural Chemistry 2011年第10期30卷 1375-1380页

作者： Saeed Reza Emamian Jamileh Nabavi Fatemeh Shams Ehsan Zahedi Chemistry Department Shahrood BranchIslamic Azad University

DFT methods have been used to study the hetero diels-alder reaction of thiazole and isothiazole with thiophen-2,5-dione.The thermodynamic and kinetic parameters were calculated.The relative stabilities of the transition structures corresponding to the endo/exo stereoisomers have been rationalized on the basis of the secondary molecular orbital interactions.NBO analysis was carried out to calculate the synchronicity index.It was shown that all reactions are synchronous.A HOMO-LUMO energy gap shows both reactions are normal electron demand.

关键词： diels-alder DFT kinetics thiazole isothiazole HOMO-LUMO gap

Synthesis and Characterization of Butyl Acrylate-based Graft Polymers with Thermo-responsive Branching Sites via the diels-alder Reaction of Furan/Maleimide

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Chinese Journal of Polymer Science 2018年第9期36卷 1011-1018页

作者： Lin Ye Shao-Feng Zhang Yi-Chao Lin Jia-Kang Min LI Ma Tao Tang State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China University of the Chinese Academy of Sciences Beijing 100049 China

Thermo-responsive butyl acrylate/furfuryl methacrylate copolymer-based （PBF backbone） graft （co）polymers with dynamic covalent linkages between their backbones and side chains via the diels-alder reaction of furardmaleimide were synthesized. Atom transfer radical polymerization （ATRP） was used to synthesize graft copolymers with thermo-responsive transformation from graft copolymers to linear polymers with bimodal or wide MWD. The NMR measurements indicated that the diels-alder reaction and retro- diels-alder reaction occurred, depending on the change of the temperature, meaning that the side chains could be cleaved and reformed according to the variation of the temperature. GPC measurements demonstrated that the molecular weights of the polymers were thermo- responsive. Furthermore, three graft copolymers with various branching chains （PBF-g-PBA, PBF-g-P（BMA-co-MA） and PBF-g-PBMA） were compared to study the influence of compatibility between the backbone and the branching chain on the efficiency of diels-alder reaction after the cleavage of the DA linkage. The results showed that the ability of the side chains to come back to the main chain was strongly affected by the compatibility between the backbone and the side chains and the flexibility of the polymer chains.

关键词： Thermo-responsive Furan/maleimide ATRP diels-alder Acrylate

A Novel Thermomorphic System for Electrocatalytic diels-alder Reactions

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Chinese Journal of Chemistry 2019年第6期37卷 557-560页

作者： Yasushi Imada Naoki Shida Yohei Okada Kazuhiro Chiba Department of Applied Biological Science Tokyo University of Agriculture and Technology3-5-8 Saiwai-choFuchuTokyo 183-8509Japan Department of Chemical Engineering Tokyo University of Agriculture and Technology2-24-16 Naka-choKoganeiTokyo 184-8588Japan

The discovery that lithium bis(trifluoromethane)sulfonamide (LiTFSI)/1-nitropropane (PrNO2) solution functions as a less polar alternative to lithium perchlorate (LiClO4)/nitromethane (MeNO2) solution has led to the development of a novel thermomorphic system for electrocatalytic diels-alder reactions. Methyl cyclohexane (Me-c-Hex) can form a monophasic condition with LiTFSI/PrNO2 solution at room temperature, enabling the use of hydrophobic dienophiles. After the electrochemical reaction, a biphasic condition can be formed at –50℃, where the cycloadducts are selectively recovered from the upper Me-c-Hex phase and the remaining lower LiTFSI/PrNO2 solution can be reused.

关键词： thermomorphic system electro catalytic diels-alder reaction electrochemistry synthetic methods cycloaddition

Glycyrrhizic acid based self-assembled helical nanostructures as scaffolds for asymmetric diels-alder reaction

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Chinese Chemical Letters 2019年第5期30卷 966-968页

作者： Yimeng Sun Yan Meng Jian Jiang Hui Sun Tiesheng Li College of Chemistry and Molecular Engineering Zhengzhou UniversityZhengzhou 450001China National Centre for Nanoscience and Technology Beijing 100190China

Glycyrrhizic acid(GA),as a traditional herbal,can self-assemble into helical nanofiber in the water.The formed helical nanostructures can be employed as scaffolds for asymmetric diels-alder reaction.Through co-assembling with a series of achiral copper-ligands,the chirality of GA helical nanostructures can be transferred to catalytic site,and resulted assemblies showed moderated enantioselectivity toward catalysis of diels-alder reaction.

关键词： Glycyrrhizic acid Helical nanofiber Co-assembly Asymmetric catalysis diels-alder reaction

Organocatalytic Domino-methylenation/diels-alder Reactions

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复旦学报（自然科学版） 2007年第5期46卷 600-601页

作者： Andreas Goeke Shanghai Givaudan Ltd Pu Dong Zhang Jiang High-Tech Park

1 Results Organocatalytic reactions are currently very much en vogue as the term implies a connotation of ecologically benign chemistry.In addition,beautiful new results have been achieved over the last few years which triggered a dramatic increase in publications[1].Related to this topic is the catalysis of organic transformations by hydrogen bond donors and organic Brnsted acids[2].From an industrial point of view,these reactions can be beneficial when performed in water in high concentration,prerequ...

关键词： diels-alder organocatalysis methylenation selectivity odor

基于diels-alder点击反应构建壳聚糖-O-聚乙二醇接枝共聚物

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高分子学报 2013年第7期23卷 903-908页

作者：金玉存卢毅於麟曹墨源熊晗王利群蒋宏亮浙江大学高分子系杭州310027 浙江大学高分子合成与功能化教育部重点实验室杭州310027

通过diels-alder(D-A)反应,合成了具有规整化学结构的接枝共聚物,壳聚糖-O-聚乙二醇(CS-O-PEG).D-A反应所需双烯体(呋喃环)通过糠基硫醇与端甲基丙烯酸酯聚乙二醇之间的巯基-丙烯酸酯(thio-acrylate)反应合成得到;马来酰亚胺基丙酸通过... 详细信息

通过diels-alder(D-A)反应,合成了具有规整化学结构的接枝共聚物,壳聚糖-O-聚乙二醇(CS-O-PEG).D-A反应所需双烯体(呋喃环)通过糠基硫醇与端甲基丙烯酸酯聚乙二醇之间的巯基-丙烯酸酯(thio-acrylate)反应合成得到;马来酰亚胺基丙酸通过活泼酯法偶联到十二烷基硫酸钠-壳聚糖复合物(SCC)羟基上,从而获得亲双烯体.采用红外光谱(FTIR)和核磁共振(1H-NMR)表征了中间产物与最终产物的结构,并用原位核磁监测D-A反应及其逆反应过程.结果表明,聚乙二醇双烯体可在水介质中温和条件下定量接枝到壳聚糖羟基上,反应具有点击特征;同时,聚乙二醇与壳聚糖之间的连接键在高温下(90℃)可通过D-A逆反应而发生断裂.

关键词：壳聚糖 diels-alder 聚乙二醇原位核磁