共查询到17条相似文献,搜索用时 469 毫秒
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N—芳基氮氧方酸与HMPA的反应 总被引:2,自引:0,他引:2
N-芳基氮氧方酸与HMPA的反应*陈益钊李聚才(四川大学化学系成都610064)黄锋(中国人民解放军防化研究院北京102205)陈凌勇(泸州医学院泸州646000)关键词N-芳基氮氧方酸六甲基磷酰胺酰胺的酸解环丁烯二酮方酸化学中图分类号O624.42... 相似文献
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首次报道了方酰胺催化环状磺酰亚胺α-位的不对称胺化反应。以N-环状磺酰亚胺与偶氮二羧酸酯为原料,在方酰胺催化下经Michael加成反应构建C-N键,合成了一系列新型糖精衍生物;1-(1,1-二氧代苯并异噻唑-3-基)-1-肼二甲酸二苄酯丁烷经还原、关环反应得含尿素结构的并环衍生物,其结构经1H NMR,13C NMR和HR-MS表征。并考察了反应温度、反应时间和底物结构对胺化反应的影响。结果表明,以奎宁方酸胺为催化剂时,最佳反应条件为:二氯甲烷为溶剂,4MS为添加剂,于-30℃反应24 h,收率95%~99%,84%e.e.~94%e.e.。 相似文献
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曾合成并研究了以1,3-双苯氨基方酸内翁盐为骨架,在苯环的2-位对称引入多甘醇醚链的双臂型方酰胺多齿配体,其中某些化合物既能作为配体对UO~2^2^+及ZγO^2^+等刚性离子配位,又能与配体NH~3发生作用,以它作为中性载体的氨选择性电极可望用于NH~3的测定。在脂肪胺的方酸内翁盐型多齿配体中,因无芳环的共轭,四碳环及其上氧之电荷状态将有所不同,这必将影响整个分子的性质。本文对这类化合物的合成进行探索,找到了行之有效的合成方法,并由此制得了九个方酰胺配体5(a~i),其中5i可作为聚酰胺等的稳定剂,其余均未见文献报道。 相似文献
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以方酸二甲酯及N-酰基-L-脯氨醛为原料,合成了4种新型方酰胺-N-酰基吡咯烷双功能手性催化剂,利用~1H NMR,~(13)CNMR,HR-MS,IR对催化剂结构进了表征。将该类催化剂应用于2,4-戊二酮对硝基烯烃的不对称Michael加成反应中,考察了溶剂、温度和催化剂用量对反应的影响,得到的最优反应条件为:甲苯为溶剂,催化剂用量为0.5 mol%,室温下反应。在最优反应条件下,以3a为催化剂,合成了12个具有光学活性的3位取代的2,4-戊二酮,最高产率达到97%,最高ee值达到95%。该催化体系能够适合含有吸电子和供电子基团的各种硝基烯烃的不对称加成。 相似文献
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N—取代—α—氧代环十二烷基磺酰胺的合成及其杀菌活性 总被引:13,自引:0,他引:13
以易得的环十二酮为原料,由磺化获得中间体α-氧代环十二烷基磺酸后,再经生成磺酰氯和胺化反应合成了一系列N-取代-α-氧代环十二烷基磺酰胺。生物活性测定结果表明,它们对小麦赤霉病菌的生长具有抑制作用,其中活性最高的是氮上取代有一氯苯基的化合物,通过构象分析讨论了它们的结构-活性关系。 相似文献
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N-方酰麻黄碱配体的合成及催化前手性芳酮的不对称还原反应 总被引:2,自引:0,他引:2
方酸与醇反应成方酸二酯,后者与天然麻黄碱反应得到N-方酰麻黄碱或N-方酰双麻黄碱。单N-方酰麻黄碱与脂肪胺及硫氢化钠等反应合成了C-3位含氮和含硫的系列配体。首次将这些方酰麻黄碱配体经原位制备手性恶唑硼烷催化前手性芳酮及二酮的不对称还原反应,得到化学产率和e.e.值分别为85%-98%和52.5%-87.4%的手性仲醇。新化合物的结构已IR,^1H NMR,MS和元素分析所证实,化合物4b的晶体结构用X射线射确认。 相似文献
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Prof. Dr. David Monge Dr. Hao Jiang Yolanda Alvarez‐Casao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(12):4494-4504
This Concept article summarizes strategies and developments regarding the use of masked unsaturated esters/amides in asymmetric organocatalysis. Useful substrates are categorized by the design of their inherent carboxylate template. This template group not only enables their functionality as ester surrogates, but also define their accessibilities, modes of interactions with catalysts and the simplicity with which they transform back to the parent carboxylates. Both covalent and noncovalent catalytic systems are discussed and examples showing the entire process (from substrates‐to‐functionalized ester/amides) are given. 相似文献
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Nickel‐Catalyzed N‐Arylation of Primary Amides and Lactams with Activated (Hetero)aryl Electrophiles 下载免费PDF全文
Christopher M. Lavoie Preston M. MacQueen Prof. Dr. Mark Stradiotto 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(52):18752-18755
The first nickel‐catalyzed N‐arylation of amides with (hetero)aryl (pseudo)halides is reported, enabled by use of the air‐stable pre‐catalyst (PAd‐DalPhos)Ni(o‐tolyl)Cl ( C1 ). A range of structurally diverse primary amides and lactams were cross‐coupled successfully with activated (hetero)aryl chloride, bromide, triflate, tosylate, mesylate, and sulfamate electrophiles. 相似文献
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Kai Yang Yixian Lou Chenglan Wang Liang‐Wen Qi Tongchang Fang Feng Zhang Hetao Xu Lu Zhou Wangyang Li Guan Zhang Peiyuan Yu Qiuling Song 《Angewandte Chemie (International ed. in English)》2020,59(8):3294-3299
A new chiral Brønsted acid, generated in situ from a chiral phosphoric acid boron (CPAB) complex and water, was successfully applied to asymmetric indole reduction. This “designer acid catalyst”, which is more acidic than TsOH as suggested by DFT calculations, allows the unprecedented direct asymmetric reduction of C2‐aryl‐substituted N‐unprotected indoles and features good to excellent enantioselectivities with broad functional group tolerance. DFT calculations and mechanistic experiments indicates that this reaction undergoes C3‐protonation and hydride‐transfer processes. Besides, bulky C2‐alkyl‐substituted N‐unprotected indoles are also suitable for this system. 相似文献
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Synthesis of Amides and Phthalimides via a Palladium Catalyzed Aminocarbonylation of Aryl Halides with Formic Acid and Carbodiimides 下载免费PDF全文
A novel method for the preparation of amides and phthalimides has been developed. The process involves a palladium catalyzed aminocarbonylation of an aryl halide, using a carbodiimide and formic acid as the carbonyl source. Experimental data suggest that the mechanistic pathway for this process involves in‐situ generation of carbon monoxide from the reaction of formic acid with a carbodiimide in the presence of a palladium catalyst. The method can be used to produce a variety of amides and N‐substituted phthalimides efficiently. 相似文献
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Zhuang Qi Shan-Shan Li Lin Li Qi Qin Li-Miao Yang Ying-Kang Liang Yun Kang Dr. Xiang-Zhi Zhang Dr. Ai-Jun Ma Prof. Dr. Jin-Bao Peng 《化学:亚洲杂志》2021,16(5):503-506
Amide synthesis is one of the most important transformations in organic chemistry due to their ubiquitous presence in our daily life. In this communication, a palladium catalyzed cascade azidation/carbonylation of aryl halides for the synthesis of amides was developed. Both iodo- and bromobenzene derivatives were transformed to the corresponding amides using PdCl2/xantphos as the catalyst system and sodium azide as the nitrogen-source. The reaction proceeds via a cascade azidation/carbonylation process. A range of alkyl and halogen substituted amides were prepared in moderate to good yields. 相似文献
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茂基稀土胺化物催化ε-己内酯开环聚合 总被引:5,自引:0,他引:5
聚己内酯(PCL)是一种可生物降解的高分子材料,有良好的相溶性,可用于药物的缓释放.近年来,用稀土化合物作为单组分催化剂催化己内酯开环聚合的研究,已成为人们关注的热点.杜邦公司的McLain等[1,2]最早发现了单组分烷氧基稀土化合物可以在室温下催化... 相似文献