三溴化金催化端炔与二芳基二硒醚反应合成炔基硒醚

炔基硒醚是合成一些有机硒化合物的重要起始物。本文研究发现,在三溴化金(Au Br3)催化下,端位炔和二芳基二硒醚在弱碱(如碳酸钾)存在下反应,生成炔基芳基硒醚,产率为69%~98%;在空气参与下,于80℃下进行反应,反应条件简单,且二硒醚的两个硒原子均可以被利用。二甲基亚砜(DMSO)是合适的溶剂,在极性较小的溶剂(如甲苯、四氢呋喃)中,此反应不能进行。芳基炔(如苯乙炔、对甲基苯乙炔、对氯苯乙炔等)、烯基炔(如环己烯乙炔)和烷基炔(如1-壬炔)均能顺利进行此反应。当芳基炔苯环的间位或邻位连有取代基时,反应产率较低(69%~82%),而对位无论是连有吸电子基还是给电子基,该反应均可以得到很高的产率(95%)。     

可见光催化的高炔丙醇经过1,4芳基迁移实现二氟烷基化反应

报道了可见光催化的高炔丙醇经过1,4芳基迁移实现二氟烷基化反应,其中以常见的二氟溴乙酸乙酯作为二氟烷基化试剂,以磷酸氢二钠为碱,反应以N,N-二甲基乙酰胺（DMA）和1,2-二氯乙烷（DCE）的混合溶剂,在室温条件、可见光照射条件下实现的.反应中各种取代基的高炔丙醇都可以很好地得到相应的二氟烷基化产物.该反应为合成一系列二氟戊酸乙酯类化合物提供了简单高效的方法.     

钯催化偶联-消去法合成芳基末端炔的研究进展

钯催化偶联-消去法合成芳基末端炔的研究进展;芳炔;偶联反应;钯催化剂;合成;综述     

端位炔酮与有机锌试剂的自缩合反应

端位炔酮与有机锌试剂CF3CO2ZnEt作用发生自缩合反应,得到较高产率的β取代的Morita-Bayllis-Hillman产物,提供了三取代烯烃化合物的合成方法;而与有机锌试剂CF3CO2ZnCH2I作用时,烷基炔酮不发生反应,只有活性较高的芳基炔酮才能进行反应,得到中等产率的2,5-二氢呋喃衍生物。     

CsOH／KOH体系促进端炔硒化合成炔硒醚

在无水THF-HMPA中,CsOH/KOH体系促进端炔与芳硒基溴反应,合成了一系列炔芳基硒醚,产率60%～73%.其结构经1H NMR,13C NMR和MS表征.     

炔基取代的新型β-内酰胺化合物的合成

首次报道了以芳香炔醛为起始原料,通过二聚反应、氧化反应、Michael加成及内酰化缩合反应合成了一系列芳炔基取代的新型四元β-内酰胺类化合物,收率57.6%~72.5%,其结构经1H NMR,13C NMR和X-射线单晶衍射表征。     

铜催化双炔膦氧化物硅质子化反应合成β-硅基取代的乙烯基膦氧化物（英文）

报道了铜催化双炔基膦氧化物单侧硅质子化合成β-硅基取代乙烯基膦氧化物的反应.各种(杂)芳基和烷基取代的二炔膦氧化物能够以中等和较高的产率和较高的化学选择性得到相应的目标产物.产物中未反应的炔基可以被进一步衍生为其它官能团.     

炔醛参与的直接Mannich反应

首次报道了炔醛参与的Mannich反应。以布朗斯特酸为催化剂,THF为溶剂,芳基炔醛,酮和脂肪胺经Mannich反应合成了一系列新型的含炔基的β-氨基酮,其结构经1H NMR,13C NMR和HR-MS表征。     

双齿氮配体钯配合物催化的羰化反应研究

研究了双齿氮配体钯（II）配合物催化剂（1-3）在对邻溴碘苯与胺的羰化合成酰胺反应以及炔烃的氧化羰化制备炔酸酯反应中的催化性能,考察了不同条件下催化剂的催化活性并对其反应产物进行了表征.研究结果表明该催化剂在酰胺化合成氮取代邻苯二甲酰亚胺的反应中表现出了较好的催化活性和选择性,分离收率和选择性高达88%和85%;在芳基...     

镍催化的芳基硼酸偕二氟炔丙基化反应

偕二氟炔丙基取代的芳烃是一类非常重要的化合物, 但传统合成该类化合物的方法却存在很大局限性. 以过渡金属催化直接向芳烃偕二氟炔丙基化是一种高效简洁制备上述化合物的方法. 以廉价易得的Ni(NO₃)₂·6H₂O为催化剂, 首次实现了镍催化下芳基硼酸与α,α-二氟炔丙基溴的偶联反应. 该反应不仅温和高效、原料廉价易得、官能团兼容性良好, 而且还能进行克量级放大和对生物活性分子的后期氟修饰, 从而为新药研发提供了一种有效手段.     

2,5-二芳基取代基-1,3,4-噁二唑类衍生物的合成与表征

以双酰肼环合法合成了含1,3,4-噁二唑结构单元的溴代芳卤,然后通过Sonogash ira钯催化偶联作用与不同单取代炔反应合成了3个新的2,5-二取代-1,3,4-噁二唑类小分子衍生物,其结构经DSC,1H NMR,IR和元素分析表征。     

Asymmetric Hydrogenation of Furans and Benzofurans with Iridium–Pyridine–Phosphinite Catalysts

Enantioselective hydrogenation of furans and benzofurans remains a challenging task. We report the hydrogenation of 2‐ and 3‐substituted furans by using iridium catalysts that bear bicyclic pyridine–phosphinite ligands. Excellent enantioselectivities and high conversions were obtained for monosubstituted furans with a 3‐alkyl or 3‐aryl group. Furans substituted at the 2‐position and 2,4‐disubstituted furans proved to be more difficult substrates. The best results (80–97 % conversion, 65–82 % enantiomeric excess) were obtained with monosubstituted 2‐alkylfurans and 2‐[4‐(trifluoromethyl)phenyl]furan. Benzofurans with an alkyl substituent at the 2‐ or 3‐position also gave high conversions and enantioselectivity, whereas 2‐aryl derivatives showed essentially no reactivity. The asymmetric hydrogenation of a 3‐methylbenzofuran derivative was used as a key step in the formal total synthesis of the cytotoxic naphthoquinone natural product (?)‐thespesone.     

Efficient solvent-free selective monoalkylation of arylacetonitriles with mono-, bis-, and tris-primary alcohols catalyzed by a Cp*Ir complex

Our objectives were to develop catalytic atom-economic processes accessing and/or incorporating versatile functionality using aryl/heteroaryl acetonitriles as substrates. We report essentially solvent-free [Cp*IrCl2]2 catalyzed redox neutral processes whereby substituted acetonitriles react with primary alcohols to deliver monosubstituted aryl/heteroaryl acetonitriles in excellent yield. We further demonstrate that such processes can be achieved by conventional or microwave heating and that bis- and tris-primary alcohols are also processed efficiently.     

She-She Interactions in a Polymer Matrix. Functionalization of Chloromethylated Crosslinked Poly-Styrene With Alkyl and Aryl Substituted Amines

Chloromethylated crosslinked polystyrene reacted with various alkyl and aryl substituted amines and besides the dispiacement reaction, additio-nai crosstinking took place. In reactions with disubstituted amines, e.g. piperidine or morphoiine, only substitution was observed, while in the case of monosubstituted amines additional crosslinking accompanying the dispiacement reaction depended on the structure of the amine, the degree of functionalization of the polystyrene, and the molar ratio between the Chloromethylated groups and the monosubstituted amines. Higher functionalization of polystyrene favoured a higher degree of additional crosslinking of the polystyrene network.     

Facile One‐Pot Synthesis of Monosubstituted 1‐Aryl‐1H‐1,2,3‐triazoles from Arylboronic Acids and Prop‐2‐ynoic Acid (=Propiolic Acid) or Calcium Acetylide (=Calcium Carbide) as Acetylene Source

The synthesis of monosubstituted 1‐aryl‐1H‐1,2,3‐triazoles was achieved in a one‐pot reaction from arylboronic acids and prop‐2‐ynoic acid or calcium acetylide (=calcium carbide), respectively, as a source of acetylene, with yields ranging from moderate to excellent (Scheme 1, Table 2). The reaction conditions were successfully applied to arylboronic acids, including analogs with various functionalities. Unexpectedly, the 1,2,3‐triazole moiety promoted a regioselective hydrodebromination (Scheme 2).     

Intermolecular alkyne hydroaminations involving 1,1-disubstituted hydrazines

[reaction: see text] Two readily prepared catalysts have been developed for the hydroamination of alkynes by 1,1-disubstituted hydrazines. The catalyses are facile with terminal alkynes and some internal alkynes. If the hydrazine bears an aryl group, Fischer cyclization can occur in a one-pot procedure. In addition, reactions with acetylene to produce a plethora of hydrazones are described. Catalytic reactions involving acetylene and substituted hydrazines are complete in less than 2 h at room temperature and 1 atm of pressure.     

Triphenylsilyl as a protecting group in the synthesis of 1, 12-heterodisubstituted p-carboranes

A triphenylsilyl group is used as an auxiliary in the synthesis of heterodisubstituted p-carboranes via triphenylsilyl-p-carborane (1). The preparation of 1 is statistical, but with recovery of the starting p-carborane, the effective conversion to 1 is about 90%. Carborane 1 has been easily converted to its lithium and copper derivatives, which were reacted with a range of electrophiles including alkyl halides: an aryl iodide, an acetylene bromide, and a sulfenyl chloride. The derivatives of 1 are crystalline and UV active, which facilitates their isolation and purification. The Ph(3)Si group is efficiently removed with fluoride to give monosubstituted p-carboranes I, which upon further nucleophilic substitution yield p-carboranes II. The yields of heterodisubstituted products II are higher than for direct, "statistical" syntheses. For example, 12-pentyl-1, 12-dicarba-closo-dodecaborane-1-carboxylic acid was synthesized from p-carborane via 1 in 62% overall yield, a considerable improvement over the 44% yield obtained by direct methods.     

A new strategy for the synthesis of coumarin- and quinolone-annulated pyrroles via Pd(0) mediated cross-coupling followed by Cu(I) catalyzed heteroannulation

The sequential coupling and cyclization reactions between aryl halides and (trimethylsilyl)acetylene (TMSA) with concurrent elimination of the TMS substituent, allows a straightforward synthesis of substituted pyrano[3,2-e]indolone and pyrrolo[3,2-f]quinolone derivatives in excellent yields.     

Palladium-catalyzed cyclization and cross-coupling of acetylenic aryl triflates with organotin reagents

Acetylenic aryl triflates reacted readily with vinyltributyltin, allyltributyltin, 1-(trimethylsilyl)-2-(tributylstannyl)acetylene, and trimethylsilyltributyltin in the presence of a palladium catalyst to produce (Z)-indanylidene and (Z)-tetralinylidene substituted compounds, the stereospecificity of the reactions for the synthesis of these compounds being ≥98%.     

Synthesis of three asymmetric N-confused tetraarylporphyrins

Two monosubstituted and one tetrasubstituted N-confused porphyrins (1-3) were prepared in ca. 3-5% yields using a [2 + 2] synthesis. The monosubstituted porphyrins have carbomethoxy (1) or nitro (2) substituents on one of the meso-phenyl groups, while the meso-phenyl groups of the third NCP (3) are substituted with nitro, bromo, and methyl groups in an AB(2)C pattern. The specific regiochemistry of the aryl rings around the macrocycle in each porphyrin was definitively determined using a combination of 1D ((1)H and (13)C) and 2D (gHMBC, gHSQC and ROESY) NMR spectroscopy. The absorption spectra of 1-3 in CH(2)Cl(2) are similar to those of N-confused tetraphenylporphyrin (NCTPP) but have Soret and Q bands that are shifted to lower energies with smaller extinction coefficients in comparison to those for NCTPP.