兴斯堡反应

兴斯堡反应用来区别分离伯、仲、叔胺有许多局限性.其表现在:一些高级伯胺的苯磺酰胺不溶于碱,叔胺与苯磺酰氯起反应,叔脂胺和叔苯胺与苯磺酰氯反应类型不同.立体效应较大的伯胺及双官能团的两性化合物都不能用来做为未知物.     

修饰金鸡纳碱催化的不对称烯丙基烷基化反应

以修饰金鸡纳碱的手性叔胺为催化剂,Morita-Baylis-Hillman碳酸酯与α-取代的β-酮酸酯经不对称烯丙基烷基化反应,以中等收率及较好的非对映选择性和对映选择性合成了一系列具有连续季碳叔碳手性中心的新型烷基取代β-酮酸酯类化合物,其结构经1H NMR和13C NMR表征。     

高对映选择性的有机催化的二氟烯醇硅醚与β,γ-不饱和-α-酮酸酯的不对称Mukaiyama-aldol反应

首次研究了二氟烯醇硅醚1与β,γ-不饱和酮酸酯2的反应.发现不论使用叔胺或叔胺-氢键给体双功能催化剂,均专一地发生Mukaiyama-aldol反应生成相应的叔醇3.利用手性氢化奎宁衍生的双功能脲催化剂11高对映选择性地实现了这一反应,为合成α-二氟烷基取代的手性叔醇提供了一种新方法.不同芳基取代的二氟烯醇硅醚以及γ位不同芳基取代的酮酸酯化合物均反应良好.在所考察的15个例子中,反应产率中等到良好(44%～81%),对映选择性中等到优秀(72%～96%).反应产物可方便转化为二氟烷基取代的手性二醇或三醇化合物.     

亚硝胺的分析化学

亚硝胺的形成和性质 N-亚硝基化合物通常分为两大类——亚硝胺类和亚硝酰胺类。亚硝胺类化合物(以下简称亚硝胺,NA＇s),是指二烷基亚硝胺〔如二甲基亚硝胺,(CH_3)_2N-NO,DMNA〕、烷基芳基亚硝胺〔如甲基苯基亚硝胺,二芳基亚硝胺(如二苯基亚硝胺(C_6H_5)_2N—NO〕和环仲胺类的亚硝基化合物〔如亚硝基毗咯烷,,和亚硝基哌啶,等。亚硝酰胺是指含有或通式的化合物,如N-甲基-N-亚硝基脲CO     

正、叔十二烷基硫醇在铜表面上自组装膜测试

研究了正、叔十二烷基硫醇在铜表面上的自组装及混合自组装成膜情况,并利用交流阻抗和极化曲线电化学方法测试了正、叔十二烷基硫醇在铜表面上自组装膜及混合自组装膜对铜的耐腐蚀性,考察了正十二烷基硫醇自组装膜质量与正十二烷基硫醇溶液的浓度及组装时间的关系。研究结果显示,混合自组装膜的质量及其对铜的耐腐蚀性比仅组装正或叔十二烷基硫醇均有很大的提高。     

水溶性氧杂酰胺类化合物的合成及表征

以二甘醇为原料, 经氧化得到的二甘酸, 通过氯代或缩合反应得到中间体酰氯和酸酐, 二烷基胺在吡啶催化下与酰氯或酸酐发生胺解反应, 合成出系列水溶性氧杂单酰胺及氧杂双酰胺, 包括N,N-二烷基-3-氧杂-戊酰胺酸系列和N,N,N'N'-四烷基-3-氧杂-戊二酰胺系列(烷基包括甲基、乙基和丙基). 用IR和¹H NMR对合成的目标产物进行了表征.     

镍催化多氟烷基溴化物与叔胺的反应研究

本文报导了氟烷基溴化物与叔胺在Ni催化剂存在下的反应, 溴化与叔胺在零价Ni配合物存在, 室温下能生成氟烷基烯胺, 并证明溴化物与碘化物是按同一机理进行反应的, 即通过电子转移而引发的一个自由基反应过程。     

钯催化的烯烃与三嗪烷氢胺羰基化反应研究

酰胺类化合物广泛应用于医药、农药、材料、合成化学等领域,因此,新型且高效合成酰胺的方法一直具有很高的关注度.我们首次使用环状脂肪三级胺类化合物—1,3,5-三嗪烷作胺源,成功解决了钯催化的烯烃氢胺羰基化反应领域中脂肪胺对钯催化剂的毒化问题,合成了多种烷基支链酰胺化合物,并提出了可能的反应机理.     

铜催化苯甲酰胺与烷基偶氮试剂环化合成含α-取代季碳中心异喹啉二酮

发展了一种苯甲酰胺自由基自由基环化制备α-官能化叔烷基取代的异喹啉二酮的新反应。此环化反应以偶氮试剂为α-取代叔烷基自由基源物质,利用碘化亚铜/空气体系催化N-烷基-N-甲基丙烯酰基苯甲酰胺发生环化,经过串联自由基加成/环化/碳-碳键形成过程,一步构建了三重碳-碳键,以41%~71%的产率合成了一系列异喹啉二酮及其衍生物。特别值得提出得是,此研究发展了一种新型α-官能叔烷基自由基源物质,发现了一种同时引入两个α-官能叔烷基片段的串联新反应。反应底物适应范围广,反应高效,催化体系廉价实用,为具有潜在药用价值的含α-取代季碳中心的异喹啉二酮及衍生物的合成提供了一条廉价、简单、快捷的新途径。     

苯并氮杂冠醚化合物在氘代氯仿中的溶剂效应的动态~1H NMR研究

本文讨论了样品浓度对苯并氮杂冠醚化合物-氘代氯仿溶液~1H NMR镨及~1H纵向弛豫时间的影响(稀释位移效应)。在实验基础上提出了苯并氮杂冠醚化合物在氯仿中的叔胺-叔铵盐交换作用机制。以此解释了稀释位移效应,并得到了三种冠醚化合物从叔胺到叔铵盐的反应平衡常数K_2和交换速率常数k,另外,本文还讨论了冠醚环中氮原子上取代基对稀释位移效应的影响,     

Highly chemoselective metal-free reduction of tertiary amides

This communication describes the chemoselective metal-free reduction of tertiary amides to the corresponding amines. Hantzsch ester is used as a mild reducing agent for the reduction of trifluoromethanesulfonic anhydride activated amides providing the tertiary amines with high functional group tolerance.     

Novel Synthesis of Optically Active 2‐Ethylhexanoic Acid, 2‐Ethylhexanol,and 2‐Ethylhexylamine via the Asymmetric Favorskii Rearrangement

The asymmetric Favorskii rearrangement of optically active α‐haloketones, which are easily prepared from chiral menthyl‐4‐toluenesulfoxide in several steps using primary or secondary amines, yields their corresponding secondary or tertiary chiral amides. The secondary chiral amides were converted to acids or amines using acylation followed by hydrolysis or reduction. In addition, the tertiary amides were directly reduced to alcohol with Super‐Hydride^®.     

Practical synthesis of amides from alkynyl bromides, amines, and water

A general and efficient method for the synthesis of a wide range of amides is described here. The reactions were conducted under convenient conditions and provided secondary and tertiary amides in moderate to excellent yields. A variety of amines and substituted alkynyl bromides were used to investigate the scope of the reactions.     

Polymers of tertiary amines

Polymers of tertiary amines and their hydrochlorides of molecular weights in the range 300–2000 have been prepared, starting from trans-1,4-dichlorobutene-2, and primary amines. The polymers present interesting solubility properties. Variation of the reaction conditions leads to crosslinked insoluble polymers. Reaction of the soluble tertiary amine polymers with organic acid dichlorides leads to polymers of tertiary amine–amides, a new type of polymer.     

Iron‐Catalyzed CαH Oxidation of Tertiary,Aliphatic Amines to Amides under Mild Conditions

De novo syntheses of amides often generate stoichiometric amounts of waste. Thus, recent progress in the field has focused on precious metal catalyzed, oxidative protocols to generate such functionalities. However, simple tertiary alkyl amines cannot be used as starting materials in these protocols. The research described herein enables the oxidative synthesis of amides from simple, noncyclic tertiary alkyl amines under synthetically useful, mild conditions through a biologically inspired approach: Fe‐catalyzed C_α? H functionalization. Mechanistic investigations provide insight into reaction intermediates and allow the development of a mild C_α? H cyanation method using the same catalyst system. The protocol was further applied to oxidize the drug Lidocaine, demonstrating the potential utility of the developed chemistry for metabolite synthesis.     

Iron‐Catalyzed Cα?H Oxidation of Tertiary,Aliphatic Amines to Amides under Mild Conditions

De novo syntheses of amides often generate stoichiometric amounts of waste. Thus, recent progress in the field has focused on precious metal catalyzed, oxidative protocols to generate such functionalities. However, simple tertiary alkyl amines cannot be used as starting materials in these protocols. The research described herein enables the oxidative synthesis of amides from simple, noncyclic tertiary alkyl amines under synthetically useful, mild conditions through a biologically inspired approach: Fe‐catalyzed C_α H functionalization. Mechanistic investigations provide insight into reaction intermediates and allow the development of a mild C_α H cyanation method using the same catalyst system. The protocol was further applied to oxidize the drug Lidocaine, demonstrating the potential utility of the developed chemistry for metabolite synthesis.     

Supported Gold Nanoparticles for Efficient α‐Oxygenation of Secondary and Tertiary Amines into Amides

Although the α‐oxygenation of amines is a highly attractive method for the synthesis of amides, efficient catalysts suited to a wide range of secondary and tertiary alkyl amines using O₂ as the terminal oxidant have no precedent. This report describes a novel, green α‐oxygenation of a wide range of linear and cyclic secondary and tertiary amines mediated by gold nanoparticles supported on alumina (Au/Al₂O₃). The observed catalysis was truly heterogeneous, and the catalyst could be reused. The present α‐oxygenation utilizes O₂ as the terminal oxidant and water as the oxygen atom source of amides. The method generates water as the only theoretical by‐product, which highlights the environmentally benign nature of the present reaction. Additionally, the present α‐oxygenation provides a convenient method for the synthesis of ¹⁸O‐labeled amides using H₂¹⁸O as the oxygen source.     

Carbamoylimidazolium salts as diversification reagents: an application to the synthesis of tertiary amides from carboxylic acids

An efficient method for the preparation of tertiary amides from carbamoylimidazolium salts and carboxylic acids is described. The transformation occurs at room temperature and under relatively mild conditions. The carbamoylimidazolium salts are obtained from the reaction of secondary amines with N,N′-carbonyldiimidazole, followed by methylation with methyl iodide. The utility of this reaction was demonstrated in the formation of Weinreb amides and in a short synthesis of fused bicyclic amides. The introduction of this reaction now permits carbamoylimidazolium salts to be utilized in the formation of tertiary amides, ureas, carbamates and thiocarbamates under a single set of conditions.     

The ruthenium-catalyzed reduction and reductive N-alkylation of secondary amides with hydrosilanes: practical synthesis of secondary and tertiary amines by judicious choice of hydrosilanes

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.     

Palladium-catalyzed decarboxylative aminocarbonylation with alkynoic acid and tertiary amine for the synthesis of alkynyl amide

We developed a method for the synthesis of alkynyl amides via the carbonylation of alkynoic acids and C-N activation of tertiary amines. The reaction of alkynoic acid and tertiary amine with carbon monoxide using a palladium catalyst in the presence of oxygen, KI, and K₃PO₄, gave the desired alkynyl amides in good yields.