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Palladium-catalyzed Cascade Cyclization-Coupling Reaction of Benzyl Halides with N, N-Diallylbenzoylamide
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作者 Yi Min HU Yu ZHANG +2 位作者 Jian Lin HAN Cheng Jian ZHU Yi PAN 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第8期771-772,共2页
A novel type of palladium-catalyzed cascade cyclization-coupling reaction has been found. Reaction of N, N-diallylbenzoylamide 1 with benzyl halides 2 afforded the corresponding dihydropyrroles 3 in moderate to excel... A novel type of palladium-catalyzed cascade cyclization-coupling reaction has been found. Reaction of N, N-diallylbenzoylamide 1 with benzyl halides 2 afforded the corresponding dihydropyrroles 3 in moderate to excellent yields. 展开更多
关键词 PALLADIUM Heck reaction benzyl halides cyclization cascade reaction.
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Synthesis of Asymmetric 4H-1, 3, 2-Benzodioxaphosphorin 2-Sulfides from Intramolecular Cyclization Reaction
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作者 Jun Ran CHENG Jia WEN +2 位作者 Rut Lian SHAO Huan Yan CAO Run Qiu HUANG(Institute of Elemento-Organic Chemistry, Nankai University. Tianjin 300071) 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第9期731-732,共2页
Asymmetric 6-substituted-2-methoxy-4-(2,4-dichlorophenyl)-4H-1,3,2-benzodioxaphosphorin a-sulfides were prepared from intramolecular cyclization. The diastereomers were separated by column chromatography and fractiona... Asymmetric 6-substituted-2-methoxy-4-(2,4-dichlorophenyl)-4H-1,3,2-benzodioxaphosphorin a-sulfides were prepared from intramolecular cyclization. The diastereomers were separated by column chromatography and fractional crystallization. Their structures were characterized on the basis of H-1 NMR, P-31 NMR and x-ray diffraction analysis. 展开更多
关键词 4H-1 3 2-benzodioxaphosphorin DIASTEREOMER intramolecular cyclization reaction
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Studies on the cyclization reaction of D-aspartic acid
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作者 Yu Chuan Li Si Ping Pang Yong Zhong Yu 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第5期516-518,共3页
The cyclization reaction of D-aspartic acid was studied, the carboxyl groups of D-aspartic acid were protected by benzyl alcohol to give compound D-dibenzyl aspartate. Then (4R)-benzyl azetidine-2-one-4-carboxylate ... The cyclization reaction of D-aspartic acid was studied, the carboxyl groups of D-aspartic acid were protected by benzyl alcohol to give compound D-dibenzyl aspartate. Then (4R)-benzyl azetidine-2-one-4-carboxylate and meso-3,6-disubstituted piperazine-2,5-diones were synthesized via intramolecular cyclization and intermolecular cycfization of D-dibenzyl aspartate, respectively, and their structures were confirmed by ^1 H NMR and MS. Both cyclization reaction conditions were also investigated in detail. 展开更多
关键词 D-Aspartic acid cyclization reaction Azetidine-2-ones 3 6-Disubstituted piperazine-2 5-diones
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The Cyclization Reactions of Lawesson's Reagent with Bifunctional Substrates
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作者 Liang Nian HE Fei CAI +1 位作者 Xiang Hua QIN Kai LI(Institute of Organic Synthesis, Central China Normal University, Wuhan,430079) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第9期751-754,共4页
The cyclizaion reactions of Lawesson's reagent(LR) with the substrates containing two functional groups such as hydroxy groups,amino groups, has been applied to prepare the O-P-O,N-P-N type 5-membered and 6-member... The cyclizaion reactions of Lawesson's reagent(LR) with the substrates containing two functional groups such as hydroxy groups,amino groups, has been applied to prepare the O-P-O,N-P-N type 5-membered and 6-membered phosphorus heterocycles.The heterocyclizaional possibility of LR with bifunctional compounds was also discussed. 展开更多
关键词 The cyclization reactions of Lawesson’s Reagent with Bifunctional Substrates
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Metal-Free Synthesis of 2-Aminobenzothiazoles via I2-Catalyzed Tandem Cyclization Reaction of Amines and Carbon Disulfide
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作者 Ting Chen Wei Feng +2 位作者 Ruitong Yang Shanping Chen Guo-Jun Deng 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2024年第8期846-852,共7页
Comprehensive Summary,A convenient approach for the construction of 2-aminobenzothiazoles via I2-catalyzed tandem cyclization reaction of amines and carbon disulfide has been developed.The present approach starts from... Comprehensive Summary,A convenient approach for the construction of 2-aminobenzothiazoles via I2-catalyzed tandem cyclization reaction of amines and carbon disulfide has been developed.The present approach starts from simple and readily available starting materials,affording a series of 2-aminobenzothiazoles in up to 89%yields under metal-free conditions.In this work,C—H/N—H functionalization was achieved and multiple C-hetero bonds were successfully constructed in one pot. 展开更多
关键词 Sulfur heterocycles C-H functionalization cyclization Tandem reaction Transition-metal-free AMINES lodine N-Heterocycles
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Construction of Spirooxindole Skeleton Through Intramolecular Dieckmann Cyclization
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作者 Ting Wu Zhiqiang Pan Chengfeng Xia 《Natural Products and Bioprospecting》 CAS 2017年第3期275-281,共7页
A highly efficient and direct approach was developed to construct the structurally diverse spirooxindole skeleton,which is an important basic motif in natural products.Both the 3,30-pyrrolidonyl spirooxindoles and spi... A highly efficient and direct approach was developed to construct the structurally diverse spirooxindole skeleton,which is an important basic motif in natural products.Both the 3,30-pyrrolidonyl spirooxindoles and spiroindolin-2-one dlactones were 2smoothly obtained by the intramolecular Dieckmann cyclization of oxindoles in excellent yield under mild conditions. 展开更多
关键词 Dieckmann reaction cyclization SPIROOXINDOLE INDOLE
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The new modes of Palladium-catalyzed cross-coupling,dimerization and dominotetracyclization of boroxines,trans-1-Bromo-2-styrylbenzene,and bromodienynes.A personal Ph.D.and Postdoctoral research review
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作者 宋治中 《绥化学院学报》 2003年第A03期14-20,共7页
关键词 Cross-couplingreaction Suzuki reaction HECK reaction DIMERIZATION cyclization Domino reaction Palladium-cat alyzed reaction Boroxine Oligomers.
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苯乙酮一锅法合成吡唑类化合物 被引量:1
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作者 刘洋 张佳晋 +2 位作者 聂进利 彭鑫 李亦彪 《广东化工》 CAS 2024年第1期10-12,4,共4页
吡唑类化合物广泛存在于医药,农药以及功能材料分子之中,同时也是非常有价值的有机合成中间体。本论文研究了在无过渡金属催化条件下,苯乙酮衍生物与N,N-二甲基甲酰胺二甲缩醛反应合成相应的烯胺酮中间体,烯胺酮中间体与水合肼一锅法反... 吡唑类化合物广泛存在于医药,农药以及功能材料分子之中,同时也是非常有价值的有机合成中间体。本论文研究了在无过渡金属催化条件下,苯乙酮衍生物与N,N-二甲基甲酰胺二甲缩醛反应合成相应的烯胺酮中间体,烯胺酮中间体与水合肼一锅法反应高效合成吡唑类化合物。该环化反应具有合成步骤少,反应产率高,不使用昂贵过渡金属和配体等优点。所合成的吡唑产物经过气相色谱-质谱和核磁共振等进行数据表征和结构鉴定。 展开更多
关键词 苯乙酮 水合肼 吡唑 环化反应 含氮杂环
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Electrochemical Dearomative Spirocyclization of N-Acyl Sulfonamides in a Continuous-Flow Cell
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作者 Ting Liu Zhaojiang Shi +2 位作者 Yaofeng Yuan Yuqi Lin Ke-Yin Ye 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2024年第9期980-984,共5页
The development of efficient and sustainable methods to obtain spirocyclic compounds is of significance as these structures are widely found in pharmaceuticals and agrochemicals.Herein,we disclose an electrochemical d... The development of efficient and sustainable methods to obtain spirocyclic compounds is of significance as these structures are widely found in pharmaceuticals and agrochemicals.Herein,we disclose an electrochemical dearomative spirocyclization of N-acyl sulfonamides in a continuous-flow cell.The reaction is simple and efficient without external catalysts or supporting electrolytes and could be applied in a decagram-scale synthesis. 展开更多
关键词 Electrochemistry CONTINUOUS-FLOW DEAROMATIZATION SPIROcyclization SULFONAMIDES cyclization Methodology and reactions
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可见光促进三组分合成C3-芳甲基取代的咪唑并[1,2-a]吡啶衍生物
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作者 张玉凤 张杰 +3 位作者 王天骏 黄雨聪 李玉秀 刘平 《合成化学》 CAS 2024年第1期59-66,共8页
C3-芳甲基取代的咪唑并[1,2-a]吡啶衍生物在材料及药物化学领域有着广泛应用。基于自由基对亚胺C=N键的插入串联环化策略,以2-氨基吡啶衍生物、芳基甲醛为原料、芳基溴乙炔为自由基源,在可见光促进和路易斯酸协同作用下,通过三组分串联... C3-芳甲基取代的咪唑并[1,2-a]吡啶衍生物在材料及药物化学领域有着广泛应用。基于自由基对亚胺C=N键的插入串联环化策略,以2-氨基吡啶衍生物、芳基甲醛为原料、芳基溴乙炔为自由基源,在可见光促进和路易斯酸协同作用下,通过三组分串联反应,以70%~78%的产率实现了C3-芳甲基取代的咪唑并[1,2-a]吡啶衍生物的构建。目标产物结构经^(1)H NMR、^(13)C NMR和HR-MS确证。本方法无需额外添加光催化剂,操作简便、反应条件温和,具有较好的底物适用性和官能团耐受性,并且可以应用于唑吡坦的一步合成。 展开更多
关键词 可见光促进 路易斯酸 三组分反应 芳甲基化 串联环化 无外加光催化剂 咪唑并[1 2-a]吡啶
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噻吩[3,2-b:4,5-b′]双苯并呋喃类化合物的合成及光物理性质研究
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作者 杨云 岳二林 +3 位作者 高源 姬宝宝 张玉琦 王记江 《延安大学学报(自然科学版)》 2024年第2期1-7,共7页
噻吩[3,2-b:4,5-b′]双苯并呋喃稠杂环化合物是一类重要的用于有机光电材料的并五苯的衍生物,该类稠杂环化合物的合成具有十分重要的意义。以廉价的2-碘苯甲醚、4-叔丁基-2-碘苯甲醚或2,4-二叔丁基-2-碘苯甲醚为原料,通过经典的Sonogash... 噻吩[3,2-b:4,5-b′]双苯并呋喃稠杂环化合物是一类重要的用于有机光电材料的并五苯的衍生物,该类稠杂环化合物的合成具有十分重要的意义。以廉价的2-碘苯甲醚、4-叔丁基-2-碘苯甲醚或2,4-二叔丁基-2-碘苯甲醚为原料,通过经典的Sonogashira偶联反应、脱保护基反应、Glaser-Hay偶联反应、碘亲电环化反应和噻吩合成反应五步反应成功合成了一类结构新颖的稠合杂环类化合物噻吩[3,2-b:4,5-b′]双苯并呋喃。关键的中间体双苯并呋喃二碘化合物(6a)和噻吩[3,2-b:4,5-b′]双苯并呋喃化合物(1a)均由单晶衍射分析确认了结构。该反应路线原料成本低,反应操作简单,总收率较高(1a:54%;1b:40%;1c:47%)。该合成策略为获得这类稠杂环化合物提供了一种有效的合成方法,所制备的化合物具有优异的光物理性质,有望用于光电材料领域。 展开更多
关键词 噻吩[3 2-b:4 5-b′]双苯并呋喃 SONOGASHIRA偶联反应 Glaser-Hay偶联反应 碘亲电环化反应 噻吩合成反应 光物理性质
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钯催化环加成反应构建中环化合物的研究进展
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作者 皮晓琳 李鸿鹏 +4 位作者 田乙然 童应成 倪文若 袁藤瑞 唐振艳 《材料导报》 EI CAS CSCD 北大核心 2024年第12期255-266,共12页
中环化合物(7—11元环)广泛存在于许多天然产物及药物等功能分子之中,这些分子因具有优异的生物活性及特殊的骨架结构等优点,展现出极其重要的药用价值,如常见的抗癌药物紫杉醇、抗菌药物Spiroxin A等。同时,这类化合物也对化学、医药... 中环化合物(7—11元环)广泛存在于许多天然产物及药物等功能分子之中,这些分子因具有优异的生物活性及特殊的骨架结构等优点,展现出极其重要的药用价值,如常见的抗癌药物紫杉醇、抗菌药物Spiroxin A等。同时,这类化合物也对化学、医药以及材料等诸多领域产生了深远的影响。但受动力学和热力学因素影响,中环化合物的高效构建依然是一个严峻的挑战。在科研工作者们的不懈努力下,近年来发展出多个新型环加成反应催化体系,其中钯催化环加成反应凭借高效、高选择性和原子经济性等优点在该领域得到了迅猛发展。本文详细介绍了近五年国内外有关钯催化环加成反应构建中环化合物研究的最新进展,旨在为该领域的发展提供一定的帮助。 展开更多
关键词 中环化合物 钯催化 环加成反应 环化反应 反应机理
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光电联合催化烯烃自由基环合反应的研究进展
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作者 王冬寅 梁德强 《云南化工》 CAS 2024年第5期1-6,共6页
烯烃是重要的化工原料,可以制备药物、农药和涂料等高价值化学品。随着光催化和电催化氧化还原反应研究的发展,开发了将二者结合解决光/电各自局限性的光电联合催化技术。通过文献研究,根据3种不同自由基的产生方式,综述了光电联合催化... 烯烃是重要的化工原料,可以制备药物、农药和涂料等高价值化学品。随着光催化和电催化氧化还原反应研究的发展,开发了将二者结合解决光/电各自局限性的光电联合催化技术。通过文献研究,根据3种不同自由基的产生方式,综述了光电联合催化烯烃自由基环合反应的研究进展。 展开更多
关键词 光电联合催化 自由基反应 烯烃 环合反应
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有机化学中的成环反应及其逆合成分析
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作者 王清花 《山西化工》 CAS 2024年第6期13-14,31,共3页
为了深入理解有机化学中关键成环反应机制、优化反应条件及逆合成分析在合成路径设计中的应用,本研究采用了实验和理论相结合方法。以Diels-Alder反应、Mizoroki-Heck反应、环加成反应为例,分析了成环反应的实施步骤、产物的分离与纯化... 为了深入理解有机化学中关键成环反应机制、优化反应条件及逆合成分析在合成路径设计中的应用,本研究采用了实验和理论相结合方法。以Diels-Alder反应、Mizoroki-Heck反应、环加成反应为例,分析了成环反应的实施步骤、产物的分离与纯化技术及产物结构鉴定技术。结果表明,精确控制实验条件可提高成环反应的产率,逆合成分析应用为合成路径优化提供了实践指导,研究发现为有机化学领域提供了新视角。 展开更多
关键词 成环反应 反应机理 分离
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I_(2)介导的炔烃碘化环化反应的研究进展
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作者 叶圣炳 岑旭江 《化工技术与开发》 CAS 2024年第5期68-72,共5页
通过催化炔烃环化的方式构建复杂分子的研究取得了重大进展,但这些构建方法仍受限于金属或Brønsted酸催化剂对炔烃的活化。分子碘具有类似过渡金属的活性,同时具有低毒性、高性价比、商业可得和易处理等优点,用分子碘活化炔烃环的... 通过催化炔烃环化的方式构建复杂分子的研究取得了重大进展,但这些构建方法仍受限于金属或Brønsted酸催化剂对炔烃的活化。分子碘具有类似过渡金属的活性,同时具有低毒性、高性价比、商业可得和易处理等优点,用分子碘活化炔烃环的异构化,从而简便、实用地构建碳环或杂环化合物,在有机合成中引起了相当大的关注。值得关注的是,分子碘具有良好的亲炔性,I_(2)介导的炔烃碘化环化反应已被证明是一种高效构建各种碘代杂环的有效方法。本文简述了I_(2)介导的炔烃碘化环化反应的一些研究进展。 展开更多
关键词 碘分子 炔烃化合物 环化反应
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Sol-Gel Distribution of Polycondensation Reaction 被引量:1
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作者 Li Zesheng, Ba Xlnwu, Sun Jiazhong and Tang Xinyi (Institute of Theoretical Chemistry and Department of Chemistry, Mm University, Changchun) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1990年第4期317-319,共3页
A theoretical approach to polycondensation reaction of Aa-Bb type Involving intramolecular cycllzatlon has been proposed by Tang Au-chin et al.. In this paper, the theoretical sol-gel distribution is tested by polycon... A theoretical approach to polycondensation reaction of Aa-Bb type Involving intramolecular cycllzatlon has been proposed by Tang Au-chin et al.. In this paper, the theoretical sol-gel distribution is tested by polycondensation of adipic acid with trimethylol propane in a sto-ichiometric ratio of 0. 8, and the effect of intramolecular cyclization is discussed in detail. 展开更多
关键词 Polycondensation reaction Sol-gel distribution Effect of intramolecular cyclization
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“Anti-Michael” and Michael Additions in the Reactions of 2-Arylmethyliden-1,3-Indandiones with 2-Aminothiophenol 被引量:1
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作者 Jessica J. Sá nchez Garcí +8 位作者 a Alberto D. Herná ndez-Suzan Elena Martí nez-Klimova Marcos Flores-Alamo Teresa Ramí rez Apan Elena I. Klimova 《International Journal of Organic Chemistry》 2017年第1期57-81,共25页
A novel 2-indano[2,3b]-2-ferrocenyl- and 2-indano[2,3b]-2-(p-methoxy-phenyl)[1,5]benzo-2,5-dihydrothiazepine 5a,b (addition Michael/cyclization) (~30.32%), indano[2,3b]-2-ferrocenyl- and 2-(p-methoxyphenyl)[1,4] benzo... A novel 2-indano[2,3b]-2-ferrocenyl- and 2-indano[2,3b]-2-(p-methoxy-phenyl)[1,5]benzo-2,5-dihydrothiazepine 5a,b (addition Michael/cyclization) (~30.32%), indano[2,3b]-2-ferrocenyl- and 2-(p-methoxyphenyl)[1,4] benzothiazine 4a,b (addition “anti-Michael”/cyclization) (~45.43%), respectively, were obtained by the condensation of 2-ferrocenyl-and 2-(p-methoxy-phenyl)methyliden-1,3-indandiones 1a,b with o-aminothiophenol 2 in the presence of AcOH and HCl. A new “anti-Michael” addition reaction of 1,4-bis-heteronucleophile 2 into 2-arylmethyliden-1,3-indandiones was reported. As a result of this reaction the product 1a,b was obtained. The structures of the resultant compounds were elucidated by IR, 1H and 13C NMR spectroscopy, mass spectrometry, elemental and X-ray diffraction analysis. The in vitro antitumor activity of the obtained products was researched using the following human cancer cell lines: glioblastoma (CNS U-251), prostatic adenocarcinoma (PC-3), chronic myelogenous leukemia (K562), colorectal adenocarcinoma (HCT-15), mammary adenocarcinoma (MCF-7), and small cell lung cancer (SKLU) and the sulforhodamine B (SRB) method. Among these new compounds some thiazine and thiazepine derivatives showed compelling in vitro antitumor effects on cell lines K-562, HCT-15, SKLU-1 and MCF-7. 展开更多
关键词 FERROCENE Addition “Anti-Michael” reaction cyclization 1 5-Thiazepines 4-Thiazines Antitumor Cell Lines
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Microwave Irradiation Effect on Intermolecular and Intramolecular Friedel-Crafts Acylation Reaction
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作者 Yutaka Okada Arisa Fujitsu 《Green and Sustainable Chemistry》 2020年第1期18-23,共6页
The effect of microwave irradiation on the intermolecular and intramolecular Friedel-Crafts acylation of aromatic compounds was investigated. Microwave irradiation had no effect on the intermolecular reaction but had ... The effect of microwave irradiation on the intermolecular and intramolecular Friedel-Crafts acylation of aromatic compounds was investigated. Microwave irradiation had no effect on the intermolecular reaction but had an accelerating effect on the intramolecular reaction. This enhanced intramolecular reactivity that was attributed to the high probability of close proximity between the reaction sites. 展开更多
关键词 MICROWAVE Irradiation Effect FRIEDEL-CRAFTS reaction cyclization
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DFT Study on Intermolecular Cleavage Reaction of N-(2-Hydroxyphenyl)-phthalamic Acid
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作者 ZHAO Chu-feng TANG Ming-sheng WANG Hong-ming WEI Dong-hui ZHAO Jing ZHANG Shou-ren CAO Shu-xia 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2008年第6期790-792,共3页
The reaction mechanisms of intermolecular cleavage reaction of N-(2-hydroxyphenyl)-phthalamic acid were studied via the density functional theory(DFT). All geometries of the reactant, transition states, and produc... The reaction mechanisms of intermolecular cleavage reaction of N-(2-hydroxyphenyl)-phthalamic acid were studied via the density functional theory(DFT). All geometries of the reactant, transition states, and products were optimized at the B3LYP/6-31G(d, p) level. Vibration analysis was carried out to confirm its identity as transitions' structure, and the intrinsic reaction coordinate method(IRC) was used to search the minimum energy path. Two possible reaction channels are reported in this article. The calculated results indicate that O-cyclization reaction channel has the lower activation barrier, and therefore, it occurs more easier than the other. 展开更多
关键词 Intermolecular decomposition reaction Density functional theory(DFT) O-cyclization N-cyclization N-(2-Hydroxyphenyl)-phthalamic acid
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1-甲基-3-三氟甲基-1H-吡唑-4-甲酸的合成 被引量:1
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作者 李爱军 吕恬恬 《化学研究与应用》 CAS 北大核心 2023年第4期997-1000,共4页
通过Knoevenagel缩合反应、用甲基肼闭环、再用碱进行酯的水解,得到目标产物1-甲基-3-三氟甲基-4-吡唑甲酸。以三氟乙酰乙酸乙酯为原料,对比原甲酸三乙酯和N,N-二甲基甲酰胺二甲基缩醛与之反应所得中间体对后续反应的优劣。
关键词 有机合成 工艺优化 闭环反应 克脑文盖尔缩合反应
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