芳基异方酰胺与HMPA及一些羧酰胺的反应

研究了1,3-双芳基异方酰胺与六甲基磷酰三胺(HMPA)及其它羧酰胺的反应制得了15个既含芳胺基又含脂肪基的不对称方酰胺。该反应提供了制备既含芳胺基又含二甲胺基、甲胺基和乙胺基的不对称方酰胺的较为有效的方法。对反应机理作了初步讨论。     

不对称芳基取代的方酰胺和异方酰胺的合成

Ｎ－芳基氮氧方酸的活性羟基能够被芳伯胺取代。利用这一特性，可在方酸四碳环上引入另一不同的芳胺基，即可获得不对称芳基取代的方酰胺或异方酰胺。以乙醇等为介质，芳伯胺与７种Ｎ－芳基氮方酸反应，制得２５个不对称的方酰胺和２４个不对称的异方酰胺。该合成方法优点突出，反应简便有效，通用性强。     

方酰胺催化的环状磺酰亚胺不对称胺化反应

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,4MS为添加剂,于-30℃反应24 h,收率95%～99%,84%e.e.～94%e.e.。     

亚砜及亚磺酰胺类配体催化不对称反应的新进展

亚砜及亚磺酰胺类化合物作为手性配体催化不对称反应是目前研究最为活跃的领域之一,苯环骨架以及链状骨架的亚砜及亚磺酰胺类手性配体相继成功地用于不对称反应中.主要综述了近年来含亚砜及亚磺酰胺类的手性配体催化不对称反应的研究进展.     

二乙基锌促进CO2的硅氢化反应以及CO2为C1合成子的有机胺甲酰化或脲化反应

CO₂的固定和转化具有重要研究意义,特别是采用廉价且良好生物相容性的金属催化剂将其转化为有用的有机化合物.本工作报道采用商品化ZnEt₂（1.0 mol%）可促进CO₂的硅氢化反应生成甲氧基硅醚,以及CO₂为C1合成子的有机胺甲酰化或脲化反应生成酰胺或脲类化合物.在1.0 mol% ZnEt₂存在下,CO₂和（EtO）₃SiH发生硅氢化反应,一锅选择性还原为甲氧基硅醚（CH₃OSi（OEt）₃）.考察了反应条件的影响,在1.0 MPa CO₂起始压力下,90℃反应7 h,甲氧基硅醚的产率达到约90%.当上述反应体系中存在有机胺时,则发生了CO₂为C1合成子的的有机胺甲酰化或脲化反应.当采用二级有机胺为底物时,反应生成酰胺类产物;当一级有机胺为底物时,反应主要生成脲类产物.考察了反应底物取代基的影响,含脂肪基和芳香基的二级有机胺均可发生甲酰化反应,芳香基的对位含给电子取代基时明显有利于该甲酰化反应.含脂肪基和芳香基的一级有机胺均可发生脲化反应,芳香基对位取代基的电子性质对脲化反应的影响规律不如在甲酰化反应中的明显.     

含磺酰胺基和羧苯基的异方酰胺的合成

以3-[邻(或对)羧苯胺基]-4-羟基-3-环丁烯二酮(1a, 1b)为底物,与一些磺胺反应, 成功地制得了14个新的不对称取代的异方酰胺。3a～3f和4a～4f结构上的共同特点是, 有药物作用的磺酰胺和邻(或对)氨基苯甲酸的结构单元, 通过方酸四碳环的桥接作用而共存于同一分子之中。     

新法合成酰胺荚醚萃取剂

采用混合酸酐法,通过氧杂单酰胺酸与二烷基胺反应,合成了3种酰胺荚醚萃取剂N,N,N'N'-四烷基-3-氧-戊二酰胺(烷基为正丁基、异丁基和正辛基),产率分别为84%,80%和57%.采用1H NMR和MS对合成的酰胺荚醚萃取剂的结构进行了表征.     

不对称α-烃基-α-羟基丙二酰胺衍生物的合成新方法

N,N-二甲基氨甲酰基三甲基硅烷与一系列N-甲基-N-甲氧甲基α-羰基酰胺在无水无氧、105℃的条件下反应,合成了不对称α-烃基-α-羟基丙二酰胺类化合物或不对称α-烃基-α-三甲基硅氧基丙二酰胺衍生物,收率71%～86%,其结构用元素分析、1H NMR、13C NMR和IR等方法进行了表征.通过研究反应的影响因素发现,反应底物α-羰基酰胺中与α-羰基直接相连的烃基的空间位阻是该加成反应的重要影响因素,而α-羰基直接相连的芳环上取代基的电子效应则主要影响反应完成的时间.并提出了可能的反应机理.     

手性磺酰胺有机小分子催化剂在不对称催化反应中的应用进展

有机小分子催化的不对称合成反应是目前研究最为活跃的领域之一.综述了磺酰胺类衍生物作为小分子催化剂在不对称反应(Michael加成反应、Mannich反应、羟醛缩合反应等)中的应用,讨论了磺酰胺中NH的酸性以及氢键性质在不对称催化反应中的的作用.     

钯配合物与手性方酰胺协同催化的乙烯基碳酸乙烯酯与醛的不对称脱羧环加成反应

利用金属钯与非手性膦配体原位生成的钯配合物和手性方酰胺为协同催化体系实现了乙烯基碳酸乙烯酯（VECs）与甲醛的不对称脱羧环加成反应，以良好的产率和对映选择性得到了手性叔醇类化合物.发现了有机小分子催化剂-手性方酰胺可实现该反应的不对称诱导，为通过两性离子烯丙基钯中间体的环加成反应的研究提供了新的思路.     

Two-Phase Dehydrogenation of Aryl Substituted Carbazide Compounds

Two-phase dehydrogenation, which is a new reaction of aryl substituted carbazide compounds, is described in this paper. Ten new azo compounds were synthesized by the reaction of aryl substituted carbazide compounds with a phenoxyl radical between two phases in good yields.     

氟取代聚芳醚酮低温合成及其结构研究

通过傅克酰基化反应合成4,4'-二(4-氟苯甲酰基)二苯醚、4,4'-二(五氟苯甲酰基)二苯醚、4,4'-二(4-氟苯甲酰基)二苯硫醚以及4,4'-二(五氟苯甲酰基)二苯醚4种长链双卤单体,并进一步制备了含二氮杂萘酮聚芳醚酮聚合物.通过多氟取代双卤单体在含二氮杂萘酮聚芳醚酮聚合物主链中引入氟原子.多氟取代双卤单体具有多...     

Gold-catalyzed Intermolecular Oxidation of Phenylacetylene and Allylic Sulfides: an Efficient and Practical Synthesis of α-Phenylthio Ketone

An efficient and practical synthesis of α-phenylthio ketone through gold-catalyzed intermolecular oxidation of phenylacetylene and substituted aryl(benzyl) allylic sulfides was developed. The reaction scope is fairly good with substituted aryl(benzyl) allylic sulfides, tolerating various functional groups, and the reaction affords the yields of 63%—85%.     

Palladium‐Catalyzed Amination of Aryl Sulfides with Anilines

A combination of a palladium–NHC catalyst and potassium hexamethyldisilazide enables the amination of aryl sulfides with anilines to afford a wide variety of diarylamines. The reaction conditions are versatile enough for the reaction of even bulky ortho‐substituted aryl sulfides. This amination can be applied to the modular synthesis of N‐aryl carbazoles from the corresponding ortho‐bromothioanisoles. As aryl sulfoxides undergo extended Pummerer reactions to afford ortho‐substituted aryl sulfides, the Pummerer products are thus useful substrates for the amination to culminate in efficient syntheses of a 2‐anilinobenzothiophene and an indole as proof‐of‐principle of the utility of the extended Pummerer reaction/amination cascade.     

芳基单取代炔合成方法

综述了各种芳基单取代炔的制备方法;分析了各种方法的反应机制和特点,认为钯催化偶联-消去反应合成芳基单取代炔是比较好的方法。芳基取代聚炔及其衍生物呈现出光、电、磁等许多新颖的性能。芳基单取代炔的合成对芳基取代聚炔的制备起到关键作用。参考文献69篇。     

Silylium‐Ion‐Promoted (5+1) Cycloaddition of Aryl‐Substituted Vinylcyclopropanes and Hydrosilanes Involving Aryl Migration

A transition‐metal‐free (5+1) cycloaddition of aryl‐substituted vinylcyclopropanes (VCPs) and hydrosilanes to afford silacyclohexanes is reported. Catalytic amounts of the trityl cation initiate the reaction by hydride abstraction from the hydrosilane, and further progress of the reaction is maintained by self‐regeneration of the silylium ions. The new reaction involves a [1,2] migration of an aryl group, eventually furnishing 4‐ rather than 3‐aryl‐substituted silacyclohexane derivatives as major products. Various control experiments and quantum‐chemical calculations support a mechanistic picture where a silylium ion intramolecularly stabilized by a cyclopropane ring can either undergo a kinetically favored concerted [1,2] aryl migration/ring expansion or engage in a cyclopropane‐to‐cyclopropane rearrangement.     

Copper-mediated cross-coupling of aryl boronic acids and alkyl thiols

[reaction: see text] The cross-coupling of aryl boronic acids and alkanethiols mediated by copper(II) acetate and pyridine in anhydrous dimethylformamide affords aryl alkyl sulfides in good yield with a wide variety of substituted aryl boronic acids. The method is applicable to the synthesis of aryl sulfides of cysteine.     

A convergent synthesis of polysubstituted aromatic nitriles via palladium-catalyzed C-H functionalization

A palladium-catalyzed C-H functionalization reaction for the synthesis of highly substituted aromatic nitriles is reported. The modularity of the reaction is demonstrated by the broad range of aryl iodides which can be coupled with metal cyanides and alkyl halides or aryl bromides.     

One‐Pot Sequential Propargylation/Cycloisomerization: A Facile [4+2]‐Benzannulation Approach to Carbazoles

A novel one‐pot [4+2]‐benzannulation approach to substituted carbazoles is accomplished by acid‐catalyzed C3‐propargylation of 2‐alkenyl/aryl indoles with 1‐aryl propargylic alcohols, followed by cycloisomerization. A variety of 2‐alkenylated indoles and 2‐aryl/heteroaryl indoles successfully participated in this tandem reaction with 1‐aryl/heteroaryl propargylic alcohols to provide diversely substituted and annulated carbazoles, as well as an aza[5]helicene.     

Cross-coupling of cyclopropyl- and cyclobutyltrifluoroborates with aryl and heteroaryl chlorides

Suitable conditions were found for the Suzuki-Miyaura cross-coupling reaction of potassium cyclopropyl- and cyclobutyltrifluoroborates with aryl chlorides. Both of these secondary alkyl trifluoroborates coupled in moderate to excellent yield with electron-rich, electron-poor, and hindered aryl chlorides to give a variety of substituted aryl cyclopropanes and cyclobutanes.