胺氧化羰基化合成脲的研究进展

CO是一种廉价、丰富且有用的C1分子,将其作为羰基源参与胺氧化羰基化反应是有机化学中一类重要的反应.近年来,采用胺氧化羰基化合成脲类化合物的技术路线备受关注.我们综述了催化剂参与的胺氧化羰基化合成脲类化合物的研究现状,还对胺氧化羰基化反应的发展趋势进行了展望.     

一氧化碳参与β-内酰胺化合物合成的研究进展

β-内酰胺类化合物是具有高生物活性及高应用价值的抗生素,如何高效高选择性地设计、合成该类化合物一直是有机化学研究的热点问题.由于其环状结构中具有羰基结构,利用一氧化碳(CO)作为羰源与底物分子发生羰基化反应也发展成为合成β-内酰胺的有效方法.通过该方法可以一步高效合成结构多样性且新颖的β-内酰胺化合物.综述了近年来通过不同底物分子与CO发生羰基化反应构建β-内酰胺的研究进展,并且对该方法存在的问题以及未来发展方向进行了展望.     

无过渡金属参与的羰基化反应进展

一氧化碳是来源广泛和廉价的碳一资源.直接将其作为羰基源引入有机分子中的羰基化反应是化学化工研究的前沿领域之一.近年来,无过渡金属参与的羰基化反应引起了人们的高度关注.综述了无过渡金属参与的羰基化合成醛与酮、合成酯、合成酰胺、合成酸和酸酐以及合成酰氯和醇等重要羰基化反应的研究现状,并对无过渡金属参与的羰基化反应的发展及应用前景进行了展望.     

铃木-宫浦羰化反应在合成二芳基甲酮中的应用

近年来,钯催化的芳基卤化物和芳基硼酸化合物的羰化偶联反应发展十分迅速。到目前为止,大量硼酸化合物、钯催化剂前体、配体和羰基源被用来合成二芳基甲酮,此类化合物在工业中间体、染料、药剂、天然产物等领域有着广泛的应用。本文从钯催化剂体系、转金属促进剂、羰基源及其应用方面综述了铃木-宫蒲(Suzuki-Miyaura or Suzuki)羰化反应的研究进展。钯催化剂体系从均相和非均相体系两方面介绍,其中均相催化体系包括钯催化剂前驱体、磷配体、氮杂卡宾配体的研究进展;非均相催化体系主要介绍了活性炭、石墨烯、官能化硅胶、四氧化三铁等载体多种固载钯催化剂的应用。特戊酸添加剂可改善转金属化过程,有效加速羰化偶联反应。经典的羰化Suzuki反应一般需要气体钢瓶提供压力较高的一氧化碳气体。尽管近期一些研究实现了常压一氧化碳气球作为羰基供给源,使用一氧化碳释放分子(CO-releasing molecule,CORM)替代剧毒危险的一氧化碳气体可实现更为安全绿色的羰化反应进程。在双管反应器中,有机CORM可控降解释放一氧化碳,为钯催化羰基偶联反应提供CO。在微波辐射下,过渡金属羰基化合物可为羰基化反应原位直接提供CO。     

水相中苯甲酰腙类化合物的绿色合成

酰腙类化合物含有-CO-NH-N=CH-特殊结构,通常是由醛或酮与酰肼通过缩合反应制备,因其药理活性而引起人们的广泛注意。本文在强酸性阳离子交换树脂NKC-9催化条件下,采用醛/酮与苯甲酰肼进行反应,合成了11个苯甲酰腙类化合物。反应过程通过TLC跟踪,产物以FT-IR、~1H-NMR等手段进行表征。催化剂经过简单处理可重复使用。     

糖基修饰的氨基酸类化合物的合成

通过对5种氨基酸酯化和氨基保护得到苄氧羰基氨基酸甲酯, 经肼解制备苄氧羰基氨基酸酰肼, 然后分别与3种不同的糖基异硫氰酸酯反应, 制备了相应的目标化合物15个, 且产率均在60%以上. 所有新化合物均经元素分析, IR, MS和¹H NMR确证. 同时探索了苄氧羰基氨基酸甲酯肼解的最佳反应条件.     

芳基磺酰和亚磺酸类化合物参与的偶联反应研究进展

芳基磺酰和亚磺酸类化合物参与的偶联反应是近年来发展起来的一类高效的合成方法.芳基磺酰氯、芳基亚磺酸(钠),芳基磺酰肼等可以作为脱硫性芳基化、芳磺酰化和还原性芳硫化的试剂合成各种联芳烃、芳基砜类化合物和芳基硫醚化合物.综述了近几年芳基磺酰类化合物参与的偶联反应研究发展,结合本课题组的工作,探讨了该类化合物在C—C键、C—SO2键和C—S键的构筑方面的新应用和新进展.     

铑催化的新型碳-氢羰基化反应制备酰胺

<正>Angew. Chem. Int. Ed. 2019, 58, 8887～8892酰胺是一类重要的羰基化合物,广泛存在于天然产物、药物分子和聚合材料之中.酰胺的经典合成方法是羧酸及其衍生物和胺类化合物在偶联试剂存在下的缩合反应,但是该方法会产生大量的废弃物.一氧化碳(CO)作为化学工业中价廉易得的重要C1原料,利用CO发展直接、绿色、高效、新颖的羰基化方法合成酰胺类化合物,具有重要     

α-二芳甲基-β-羰基硫代羧酸酯与肼的环合反应:官能化含5-羟基吡唑基的三芳基甲烷类化合物的合成

本文通过α-二芳甲基-β-羰基硫代羧酸酯与肼的环合反应合成了含5-羟基吡唑基的三芳基甲烷类化合物。研究表明,在乙醇回流条件下,α-二芳甲基-β-羰基硫代羧酸酯与肼能有效进行环合反应,高产率制得5-羟基吡唑基三芳甲烷类化合物。该反应条件温和、产率高、操作简单。     

a-二芳甲基-b-羰基硫代羧酸酯与肼的环合反应：官能化含5-羟基吡唑基的三芳基甲烷类化合物的合成

本文研究了合成官能化含5-羟基吡唑基的三芳基甲烷类化合物的a-二芳甲基-b-羰基硫代羧酸酯与肼的环合反应。研究表明,在乙醇介质中,回流条件下, a-二芳甲基-b-羰基硫代羧酸酯与肼能有效进行环合反应,高产率制得5-羟基吡唑基三芳甲烷类化合物。该反应条件温和,产率高,操作简单。     

Characteristic reactions of group 9 transition metal compounds in organic synthesis

Group 9 metal compounds in organic synthesis have two characteristic reactions. The first occurs because the group 9 metals have a high affinity to carbon–carbon or carbon–nitrogen π‐bonds. The first type of characteristic reactions in these group 9 metal compounds includes Pauson–Khand reactions, the Pauson–Khand‐type reactions ([2 + 2 + 1] cyclization), the other cyclizations and coupling reactions. The second occurs because the group 9 metals have a high affinity to carbonyl groups. The second type of characteristic reactions includes carbonylations such as hydroformylations, the carbonylations of methanol, amidocarbonylations and other carbonylations. The first characteristic reactions are applied for the synthesis of fine chemicals such as pharmaceuticals and agrochemicals. However, the second characteristic reactions are utilized not only for fine chemicals but also for important bulk commodity chemicals such as aldehydes, carboxylic acids and alcohols. Copyright © 2009 John Wiley & Sons, Ltd.     

Palladium‐Catalyzed Carbonylations of Aryl Bromides using Paraformaldehyde: Synthesis of Aldehydes and Esters

Carbonylation reactions represent useful tools for organic synthesis. However, the necessity to use gaseous carbon monoxide is a disadvantage for most organic chemists. To solve this problem, novel protocols have been developed for conducting palladium‐catalyzed reductive carbonylations of aryl bromides and alkoxycarbonylations using paraformaldehyde as an external CO source (CO gas free). Hence, aromatic aldehydes and esters were synthesized in moderate to good yields.     

Three characteristic reactions of organocobalt compounds in organic synthesis

Organocobalt compounds in organic synthesis have three characteristic reactions. The first occurs because cobalt has a high affinity to carbon–carbon π‐bonds or carbon–nitrogen π‐bonds. The second occurs because cobalt has a high affinity to carbonyl groups. The third is due to cobalt easily tending to form square‐planar bipyramidal six‐coordination structures with four nitrogen atoms or two nitrogen atoms and two oxygen atoms at the square‐planar position, and to bond with one or two carbon atoms at the axial position. The first characteristic reactions are the representative reactions of organocobalt compounds with a mutually bridged bond between the two π‐bonds of acetylene and the cobalt–cobalt bond of hexacarbonyldicobalt. These are reactions with a Co₂(CO)₆ protecting group to reactive acetylene bond, the Nicholas reactions, the Pauson–Khand reactions ([2 + 2 + 1] cyclizations), [2 + 2 + 2] cyclizations, etc. These reactions are applied for the syntheses of many kinds of pharmaceutically useful compounds. The second reactions are carbonylations that have been used or developed as industrial processes such as hydroformylation for the manufacture of isononylaldehyde, and carbonylation for the production of phenylacetic acid from benzyl chloride. The third reactions are those reactions with the B₁₂‐type catalysts, and they have recently been used in organic syntheses and are utilized as catalysts for stereoselective syntheses. These reactions have been used as new applications for organic syntheses. Copyright © 2007 John Wiley & Sons, Ltd.     

Oxalyl chloride as carbonyl synthon in Pd-catalyzed carbonylations of triarylbismuth and triarylindium organometallic nucleophiles

Oxalyl chloride has been demonstrated to function as C1 carbonyl synthon in the carbonylations of triarylbismuth and triarylindium nucleophiles under palladium-catalyzed conditions. All the three aryl groups from both bismuth and indium reagents participated in carbonylative couplings to afford the corresponding functionalized ketones in high yields. This study also disclosed a novel utilization of oxalyl chloride as facile alternative source of CO for carbonylations under palladium catalysis.     

Recent advances on deoximation: From stoichiometric reaction to catalytic reaction

Recent advances on the deoximation reactions are reviewed in this review. It was shown that catalytic deoximation with molecular oxygen as the mild oxidant should be the developing trend of the reaction.     

Catalytic Carbonylation and Carboxylation of Organosulfur Compounds via C−S Cleavage

Transition‐metal‐catalyzed carbonylation with CO gas occupies a privileged position in organic synthesis for the synthesis of carbonyl compounds. Although this attractive and useful chemistry has led many researchers to investigate carbonylative transformations of various organic (pseudo)halides, C?S‐cleaving carbonylation of organosulfur compounds has been fairly limited. Recently, a broad spectrum of C?S‐cleaving transformations has been emerging in the field of cross‐coupling. In light of the importance of carbonyl compounds as well as considerable advancement for employing organosulfur compounds as competent surrogates of (pseudo)halides, carbonylative transformations of C?S bonds should be of high value. This Minireview focuses on catalytic C?S carbonylation of organosulfur compounds with CO or its equivalents. In addition, reductive carboxylation of C?S bonds with CO₂ is described.     

Three types of reactions with intramolecular five-membered ring compounds in organic synthesis

There are three types of reactions with intramolecular five-membered ring compounds in organic syntheses: The first type is reactions involving intramolecular five-membered ring compounds which are utilized for the ease of synthesis of these compounds and the stability of the products. The second is reactions performed via intramolecular five-membered ring intermediates, because such intermediates are very reactive and labile compounds. The third is the metal-catalyzed reactions with the intramolecular five-membered ring compounds because these metal compounds have catalytic activities. The third type reactions involving intramolecular five-membered ring pincer compounds are also provided.The first type reactions include carbonylations, alkenylations, alkynylations, acylations, isocyanations, Diels-Alder reactions, etc. The second type reactions include carbonylations, cross-coupling reactions, hydroacylations, ring expansion reactions, carbocyclizations, etc. The third type reactions include cross-coupling reactions, rearrangements, metatheses, reductions, Michael reactions, dehydrogenations, Diels-Alder reactions, etc.     

Electrochemical dehydrogenative N–H/N–H coupling reactions

The N–N bond is present in many important organic compounds, such as hydrazines, pyrazoles, azos, etc. Many methods based on transition metal catalyzed N–N coupling or functionalization of hydrazine have been reported for the synthesis of N–N containing organic compounds. In recent years, electrochemical dehydrogenative N–H/N–H coupling has become a powerful tool for the construction of N–N bearing organic compounds. The electrochemical methods employ electrons as traceless redox reagents instead of chemicals and produce hydrogen as the only byproduct. In this review, we summarize the recent advances in the electrochemical dehydrogenative N–H/N–H coupling reactions with focus on the mechanistic insights and synthetic applications of these transformations.     

A one step synthesis of 1-alkylpyrazolo[5,4-d]pyrimidines

A new synthesis of 1-alkylpyrazolo[5,4-d]pyrimidines is described. The reaction of 4,6-dichloropyrimidine-5-carbaldehyde with various substituted hydrazines provides such compounds in a single step from commercially available starting materials. This method has advantages over methods currently described in the literature for the construction of such ring systems.     

Aryl Formate as Bifunctional Reagent: Applications in Palladium‐Catalyzed Carbonylative Coupling Reactions Using In Situ Generated CO

After decades of development, carbonylation reactions have become one of the most powerful tools in modern organic synthesis. However, the requirement of CO gas limits the applications of such reactions. Reported herein is a versatile and practical protocol for carbonylative reactions which rely on the cooperation of phenyl formate and nonaflate, and the generation of CO in situ. This protocol has a high functional‐group tolerance and could be applied in carbonylations with C, N, and, O nucleophiles. The corresponding amides, alkynones, furanones, and aryl benzoates were synthesized in good yields.