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3-芳基取代噻吩大多是电致发光材料的前体化合物. 催化剂摩尔分数为0.5% 的二茂铁亚胺环钯化合物在DMF/K3PO4/80 ℃条件下, 能够有效地催化3-噻吩硼酸同芳基碘和芳基溴的Suzuki反应, 方便地合成系列3-芳基噻吩衍生物. 此方法操作简便, 不需要加入过量的3-噻吩硼酸, 催化剂用量小. 化合物3b, 3c和3d的发射光谱和激发光谱表明, 此类化合物具有潜在的发光应用性能. 相似文献
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一级芳胺广泛用于天然产物、药物、高分子和材料的合成中, 传统合成一级芳胺是在高温、高压和封闭容器中采用钯催化卤代芳烃与氨气反应来制备, 也可以在钯催化下使用氨的替代物, 如Li[N(SiMe3)2], Zn[N(SiMe3)2]与卤代芳烃反应来合成. 显然, 这些方法有以下缺点: (a)由于采用钯催化剂和复杂的配体, 成本较高、毒性较大; (b)当使用氨气作为氨基源时, 高温、高压和封闭容器是必不可少的; (c)当使用氨的替代物作为氨基源时, 由于这些氨的替代物不易制备、成本也就较高. 清华大学化学系付华课题组建立了一种合成一级芳胺的新方法, 即在室温和常压下, 使用Cu2O作催化剂, 芳基硼酸与氨水在甲醇溶液中反应合成了一级芳胺. 反应容器不需要封闭, 不需要惰性气体保护, 也不需要在反应体系中加入任何配体或添加剂. 这种方法能够容忍各种官能团的存在, 如芳基硼酸的碳-卤键、羟基、醛基、酯基、羧基、氨基等. 这种方法反应条件温和、高效、实用, 能够广泛应用于一级芳胺的合成中. 相似文献
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三级胺的氧化是自然界中最基本的反应之一.利用化学方法研究三级胺的氧化反应不仅可以提供合成含氮化合物的新方法和途径,也可以帮助我们了解生命体中三级胺氧化的反应过程和机理.近十年,过渡金属催化的三级胺氧化反应取得了一些重要的研究进展.主要总结了近年来以过渡金属为催化剂,在氧化剂的条件下,三级胺氧化反应研究领域中的重要研究结果,并展望了该研究领域未来研究的重点和挑战性问题.主要分为五个部分:(1)三级胺的氧化形成氧化胺;(2)三级胺的氧化Mannich反应;(3)三级胺的氧化去甲基化反应;(4)三级胺的氧化酰胺化反应;(5)三级胺取代基的氧化转化. 相似文献
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2-芳基硫代芳胺的结构广泛存在于许多具有重要生理、药理活性的天然产物、药物以及材料当中, 研究此类结构的构建对这些化合物的合成路线设计可以提供新的思路. 传统合成2-芳基硫代芳胺, 常需多步骤或高温、强碱条件下进行, 能进行此类反应的反应物有限, 所得产物收率不高. 选用三氟乙酰基作为芳胺氮原子上的保护基, 利用三氟乙酰基的邻位促进效应, 并采用碘化亚铜/L-脯氨酸的催化体系, 在乙二醇二甲醚中, 碳酸钾为碱, 于60 ℃一步实现N-三氟乙酰基邻碘代苯胺与芳基硫酚的偶联, 以高产率获得了N-三氟乙酰基-2-芳基硫代芳胺. 反应条件温和, 催化体系价廉易得, 反应操作简便. 相似文献
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Biomimetic aerobic oxidation of primary benzylic amines has been achieved by using a quinone catalyst. Excellent selectivity is observed for primary, unbranched benzylic amines relative to secondary/tertiary amines, branched benzylic amines, and aliphatic amines. The exquisite selectivity for benzylic amines enables oxidative self-sorting within dynamic mixtures of amines and imines to afford high yields of cross-coupled imine products. 相似文献
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Reliable N-alkylations of secondary amines have been developed. By using DIAD and TPP (or PS-TPP) a variety of secondary amines can be converted to the corresponding tertiary amines in good to excellent yields with diverse alkylhalides; no formation of quaternary amine salts are observed. These protocols are amenable to combinatorial chemistry libraries, and are also useful for the syntheses of secondary amines by an acid lysis of the cleavable tertiary amino resins. 相似文献
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Zinc oxide (ZnO) is a highly efficient catalyst for the acylation of a variety of alcohols, phenols and amines with acid chlorides or acid anhydrides under solvent free conditions. Primary, secondary, tertiary, allylic and benzylic alcohols, diols and phenols with electron donating or withdrawing substituents can be easily acylated in good to excellent yield. 相似文献
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Unsymmetrical secondary and tertiary amines are prepared by the ruthenium catalyzed reaction of alcohols with amines, which provides highly efficient method for synthesis of cyclic amines. 相似文献
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Stereochemically defined enantioenriched molecules were, are and will always be playing a pivotal role in the development of novel pharmaceutical agents. On this line, compounds having tertiary benzylic stereocenter are of special note. This has led to an increase in the development of novel synthetic strategies for accessing molecules having this structural moiety. The current critical discussion proposes to describe the various synthetic methodologies for the enantioselective synthesis of diaryl methanols, diarylmethyl amines and other related scaffolds with tertiary benzylic stereogenic center that came up during 1995–2016. Through this critical view, we would not only like to give the readers a brief outlook on the different techniques that can be followed for the synthesis of a vast array of entities having this structural core, but also would like to highlight the limitations the protocols that need to be addressed. 相似文献
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Rapid reductive-carboxylation of secondary amines. One pot synthesis of tertiary N-methylated amines
Various tertiary N-methylated amines were synthesized by using a new reductive-carboxylation approach. Secondary amines, on carboxylation with carbon dioxide under moderate reaction conditions, afforded their corresponding carbamate esters, which, on lithium aluminum hydride reduction, gave desired tertiary N-methylated amines in high yield. 相似文献
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N. N. Makhova G. A. Karpov A. N. Mikhailyuk A. E. Bova L. I. Khmel'nitskii S. S. Novikov 《Russian Chemical Bulletin》1978,27(1):198-200
Conclusions A method was proposed for the N-nitrosation of secondary amines using N2O4 complexes in combination with tertiary amines or pyridine.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 226–227, January, 1978. 相似文献
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Selective N-alkylation of amines using nitriles under hydrogenation conditions: facile synthesis of secondary and tertiary amines 总被引:1,自引:0,他引:1
Ikawa T Fujita Y Mizusaki T Betsuin S Takamatsu H Maegawa T Monguchi Y Sajiki H 《Organic & biomolecular chemistry》2012,10(2):293-304
Nitriles were found to be highly effective alkylating reagents for the selective N-alkylation of amines under catalytic hydrogenation conditions. For the aromatic primary amines, the corresponding secondary amines were selectively obtained under Pd/C-catalyzed hydrogenation conditions. Although the use of electron poor aromatic amines or bulky nitriles showed a lower reactivity toward the reductive alkylation, the addition of NH(4)OAc enhanced the reactivity to give secondary aromatic amines in good to excellent yields. Under the same reaction conditions, aromatic nitro compounds instead of the aromatic primary amines could be directly transformed into secondary amines via a domino reaction involving the one-pot hydrogenation of the nitro group and the reductive alkylation of the amines. While aliphatic amines were effectively converted to the corresponding tertiary amines under Pd/C-catalyzed conditions, Rh/C was a highly effective catalyst for the N-monoalkylation of aliphatic primary amines without over-alkylation to the tertiary amines. Furthermore, the combination of the Rh/C-catalyzed N-monoalkylation of the aliphatic primary amines and additional Pd/C-catalyzed alkylation of the resulting secondary aliphatic amines could selectively prepare aliphatic tertiary amines possessing three different alkyl groups. According to the mechanistic studies, it seems reasonable to conclude that nitriles were reduced to aldimines before the nucleophilic attack of the amine during the first step of the reaction. 相似文献
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A triruthenium cluster, (mu3,eta2,eta3,eta5-acenaphthylene)Ru3(CO)7 (1) catalyzes the reaction of secondary amides with hydrosilanes, yielding a mixture of secondary amines, tertiary amines, and silyl enamines. Production of secondary amines with complete selectivity is achieved by the use of higher concentration of the catalyst (3 mol %) and the use of bifunctional hydrosilanes such as 1,1,3,3-tetramethyldisiloxane. Acidic workup of the reaction mixture affords the corresponding ammonium salts, which can be treated with a base, providing a facile method for isolation of secondary amines with high purity. In contrast, tertiary amines are formed with high selectivity by using lower concentration of the catalyst (1 mol %) and polymeric hydrosiloxanes (PMHS) as reducing agent. Reduction with PMHS encapsulates the ruthenium catalyst and organic byproducts to the insoluble silicone resin. The two reaction manifolds are applicable to various secondary amides and are practical in that the procedures provide the desired secondary or tertiary amine as a single product. The product contaminated with only minimal amounts of ruthenium and silicon residues. On the basis of the products and observed side products as well as NMR studies a mechanistic scenario for the reaction is also described. 相似文献
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Combination of Pd, supported on alkaline earth type supports with a lipase results in a selective catalytic system for dynamic kinetic resolution of benzylic amines. 相似文献