- Iodonium Cation-Pool Electrolysis for the Three-Component Synthesis of 1,3-Oxazoles
-
The synthesis of 1,3-oxazoles from symmetrical and unsymmetrical alkynes was realized by an iodonium cation-pool electrolysis of I2 in acetonitrile with a well-defined water content. Mechanistic investigations suggest that the alkyne reacts with the acetonitrile-stabilized I+ ions, followed by a Ritter-type reaction of the solvent to a nitrilium ion, which is then attacked by water. The ring closure to the 1,3-oxazoles released molecular iodine, which was visible by the naked eye. Also, some unsymmetrical internal alkynes were tested and a regioselective formation of a single isomer was determined by two-dimensional NMR experiments.
- Sattler, Lars E.,Hilt, Gerhard
-
supporting information
p. 605 - 608
(2020/12/07)
-
- Synthesis and Photochemical Application of Hydrofluoroolefin (HFO) Based Fluoroalkyl Building Block
-
A novel fluoroalkyl iodide was synthesized on multigram scale from refrigerant gas HFO-1234yf as cheap industrial starting material in a simple, solvent-free, and easily scalable process. We demonstrated its applicability in a metal-free photocatalytic ATRA reaction to synthesize valuable fluoroalkylated vinyl iodides and proved the straightforward transformability of the products in cross-coupling chemistry to obtain conjugated systems.
- Varga, Bálint,Tóth, Balázs L.,Béke, Ferenc,Csenki, János T.,Kotschy, András,Novák, Zoltán
-
supporting information
p. 4925 - 4929
(2021/07/01)
-
- Synthesis of Phenanthrenes via Palladium-Catalyzed Three-Component Domino Reaction of Aryl Iodides, Internal Alkynes, and o-Bromobenzoic Acids
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A new palladium-catalyzed domino alkyne insertion/C-H activation/decarboxylation sequence has been developed, which provides an efficient approach for synthesizing a variety of functionalized phenanthrenes in moderate to good yields. The method shows broad substrate scope and good functional group tolerance by employing readily available materials, including aryl iodides, internal alkynes, and o-bromobenzoic acids, as three-component coupling partners.
- Deng, Guobo,Liang, Yun,Luo, Xiai,Yang, Xiumei,Yang, Yuan,Yang, Yuzhong,Zhou, Liwei
-
supporting information
p. 1223 - 1230
(2020/04/15)
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- Fe-Catalyzed Selective Cyclopropanation of Enynes under Photochemical or Thermal Conditions
-
The nucleophilic Fe-complex Bu4N[Fe(CO)3(NO)] (TBA[Fe]) catalyzes the cyclopropanation of enynes to substituted propargyl cyclopropanes using diazoesters as carbene surrogates. The catalyst can be activated either thermally in the presence of catalytic amounts of 4-nitroanisole or under photochemical conditions. Cyclopropanation occurs selectively at the enyne moiety; alternative olefinic moieties remain intact.
- Picher, Marie-Idrissa,Plietker, Bernd
-
supporting information
p. 340 - 344
(2020/01/11)
-
- Copper-Catalyzed Ring Opening of [1.1.1]Propellane with Alkynes: Synthesis of Exocyclic Allenic Cyclobutanes
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Despite the long history and interesting properties of propellanes, these compounds still have tremendous potential to be exploited in synthetic organic chemistry. Herein we disclose an experimentally simple procedure to achieve cyclobutane-containing allenes and alkynes through a copper-catalyzed ring opening of [1.1.1]propellane and subsequent reaction with ethynes.
- Lasányi, Dániel,Tolnai, Gergely L.
-
supporting information
p. 10057 - 10062
(2019/12/24)
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- BF3·OEt2-Promoted Propargyl Alcohol Rearrangement/[1,5]-Hydride Transfer/Cyclization Cascade Affording Tetrahydroquinolines
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An efficient BF3·OEt2-mediated propargyl alcohol rearrangement/[1,5]-hydride transfer/cyclization cascade for the synthesis of tetrahydroquinoline derivatives has been described. The substituents adjacent to triple bonds play an important role in the formation of ketones (via [1,3]-hydroxyl shift) or alkenyl fluorides which are products of formal trans-carbofluorination of internal alkynes. This method provides a rapid access to diverse heterocycles in moderate to excellent yields.
- Zhao, Shuang,Wang, Xiaoyang,Wang, Pengfei,Wang, Guangwei,Zhao, Wentao,Tang, Xiangyang,Guo, Minjie
-
supporting information
p. 3990 - 3993
(2019/06/14)
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- Palladium-Catalyzed Cascade Intramolecular Cyclization and Allylation of Enynoates with Allylic Alcohols
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A Pd(II)-catalyzed mild and highly regioselective 6-endo cyclization/allylation reaction of enynoates with simple allylic alcohols has been developed. Under mild reaction conditions, the vinyl palladium species generated in situ after cyclization could insert C-C double bond of allylic alcohol through cross-coupling reaction and lead to the formation of allyl pyrone via β-OH elimination. This cascade cross-coupling reaction represents a direct and atom economic methodology for the construction of novel allyl pyrones in moderate to good yields.
- Qiu, Sheng-Qi,Ahmad, Tanveer,Xu, Yun-He,Loh, Teck-Peng
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p. 6729 - 6736
(2019/06/14)
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- DBU-Mediated Synthesis of Aryl Acetylenes or 1-Bromoethynylarenes from Aldehydes
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Two well known synthetic organic reactions Ramirez olefination and Corey-fuchs reactions are integrated in one-pot sequential manner for the synthesis of arylacetylenes and 1,3-enynes starting directly from commercially available aldehydes. The bicyclic amidine 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) along with additive NaOH not only exclusively afforded the terminal alkynes directly from the aldehydes, but also enhanced the reaction rate. The dynamic nature of DBU also facilitated the isolation of 1-bromoalkynes intermediate products. Selection of additive from NaOH and H2O served as a switch for the synthesis of terminal alkyne and 1-bromoalkynes, respectively. (Figure presented.).
- Thummala, Yadagiri,Karunakar, Galla V.,Doddi, Venkata Ramana
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supporting information
p. 611 - 616
(2019/01/04)
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- An Additive-Free, Base-Catalyzed Protodesilylation of Organosilanes
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We report an additive-free, base-catalyzed C-, N-, O-, and S-Si bond cleavage of various organosilanes in mild conditions. The novel catalyst system exhibits high efficiency and good functional group compatibility, providing the corresponding products in good to excellent yields with low catalyst loadings. Overall, this transition-metal-free process may offer a convenient and general alternative to current employing excess bases, strong acids, or metal-catalyzed systems for the protodesilylation of organosilanes.
- Yao, Wubing,Li, Rongrong,Jiang, Huajiang,Han, Deman
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p. 2250 - 2255
(2018/02/23)
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- Gold-catalyzed N,O-functionalization of 1,4-diyn-3-ols with: N -hydroxyanilines to form highly functionalized pyrrole derivatives
-
This work describes new N,O-functionalization of 1,4-diyn-3-ols with N-hydroxyanilines to yield highly functionalized pyrrole derivatives. In a postulated mechanism, N-hydroxyaniline attacks the more electron-rich alkynes via regioselective N-attack to form unstable ketone-derived nitrones that react with their tethered alkynes via an intramolecular oxygen-transfer to form α-oxo gold carbenes. This new method is applicable to a short synthesis of a bioactive molecule, a PDE4 inhibitor.
- Hsu, Yu-Chen,Hsieh, Shu-An,Li, Po-Hsuan,Liu, Rai-Shung
-
supporting information
p. 2114 - 2117
(2018/03/06)
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- Au-Catalyzed Intermolecular [2+2] Cycloadditions between Chloroalkynes and Unactivated Alkenes
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The [2+2] cycloaddition is a versatile strategy for the synthesis of strained cyclobutenes of high synthetic value. In this study, two efficient intermolecular [2+2] cycloadditions between two different types of chloroalkynes and unactivated alkene are realized with gold catalysis. Of significance is that the reaction works with challenging monosubstituted unactivated alkenes, which is unprecedented in gold catalysis and scarcely documented in other metal-catalyzed/promoted reactions; moreover, the reaction exhibits excellent regioselectivities, which are much better than those reported in literature. With 1,2-disubstituted unactivated alkenes, the reaction is largely stereospecific. The cyclobutene products can be prepared in nearly gram scale and readily undergo further reactions including various cross-coupling reactions using the C(sp2)-Cl and/or C(sp2)-SPh bond, which in turn substantially broaden the scope of accessible cyclobutenes and enhance the synthetic utility of this bimolecular reaction.
- Bai, Yu-Bin,Luo, Zaigang,Wang, Yuguang,Gao, Jin-Ming,Zhang, Liming
-
supporting information
p. 5860 - 5865
(2018/05/14)
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- α-Hydroxy-Tetrazoles as Latent Ethynyl Moieties: A Mechanistic Investigation
-
This article focuses on the dehydration of α-hydroxy-tetrazoles, leading to tetraazafulvenes and then to vinylic carbenes that rearrange into ethynyl moieties through the Fritsch-Buttenberg-Wiechell rearrangement. Each step of this sequence was scrutinized, either by examination of the substrate and/or dehydrating agent scope, or through AM1 calculations, in order to understand the limiting step of this process. This underrated transformation appears to be a viable alternative to existing methods used for transforming aldehydes into alkynes.
- Quinodoz, Pierre,Wright, Karen,Drouillat, Bruno,Kletskii, Mikhail E.,Burov, Oleg N.,Lisovin, Anton. V.,Couty, Fran?ois
-
-
- SO2F2-Mediated Oxidative Dehydrogenation and Dehydration of Alcohols to Alkynes
-
Direct synthesis of alkynes from inexpensive, abundant alcohols was achieved in high yields (greater than 40 examples, up to 95% yield) through a SO2F2-promoted dehydration and dehydrogenation process. This straightforward transformation of sp3-sp3 (C-C) bonds to sp-sp (C=C) bonds requires only inexpensive and readily available reagents (no transition metals) under mild conditions. The crude alkynes are sufficiently free of impurities to permit direct use in further transformations, as illustrated by regioselective Huisgen alkyne-azide cycloaddition reactions with PhN3 to give 1,4-substituted 1,2,3-traiazoles (16 examples, up to 92% yield) and Sonogashira couplings (10 examples, up to 77% yield).
- Zha, Gao-Feng,Fang, Wan-Yin,Li, You-Gui,Leng, Jing,Chen, Xing,Qin, Hua-Li
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supporting information
p. 17666 - 17673
(2019/01/04)
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- Na2S-mediated synthesis of terminal alkynes from: Gem -dibromoalkenes
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The Na2S-mediated facile synthesis of terminal alkynes from gem-dibromoalkenes, at 20/40 °C under open flask conditions has been developed. Various precursors derived from heteroaromatic/aromatic/aliphatic aldehydes were found compatible. The reaction is proposed to proceed through the Fritsch-Buttenberg-Wiechell (FBW) rearrangement involving the corresponding vinyl carbene. Using mild reaction conditions with inexpensive Na2S·9H2O under air atmosphere has significant advantages over earlier routes.
- Singh, Radhey M.,Nandini, Durgesh,Bharadwaj, Kishor Chandra,Gupta, Tanu,Singh, Raj Pal
-
supporting information
p. 9979 - 9982
(2017/12/26)
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- A practical non-metal catalytic silicon of the amino protection of the new method (by machine translation)
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The invention relates to a high efficiency, mild organic silicon reagent carbon silicon key fracture of the new method. The method of this reaction to the alkali is cheap and easy to obtain metal catalyst, in order to common commercial solvent as a reaction solvent and a hydrogen source, in the air and in the under mild conditions can be successfully catalytic trimethyl aryl silicon reagent or aryl alkyne base silicon reagent selectively generating carbon silicon key cracking hydrogenation reaction, the substrate universality is wide, functional group compatibility outstanding. The first innovative to realize the non-transition metal catalyzed carbon silicon key breaking reaction, also overcome the traditional method requires the use of greatly excessive inorganic alkali or an expensive metal catalyst to the limitation of the silicon of the amino protection, for the laboratory preparation and industry in the production of the organosilicon group deprotection provides a completely new strategy. (by machine translation)
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-
Paragraph 0052; 0053
(2018/04/01)
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- Enantioselective synthesis of β-fluoro-β-aryl-α-aminopentenamides by organocatalytic [2,3]-sigmatropic rearrangement
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The tetramisole-promoted catalytic enantioselective [2,3]-sigmatropic rearrangement of quaternary ammonium salts bearing a (Z)-3-fluoro-3-arylprop-2-ene group generates, after addition of benzylamine, a range of β-fluoro-β-aryl-α-aminopentenamides containing a stereogenic tertiary fluorine substituent. Cyclic and acyclic nitrogen substituents as well as various aromatic substituents are tolerated, giving the β-fluoro-β-aryl-α-aminopentenamide products in up to 76% yield, 96:4 dr, and 98:2 er.
- Kasten, Kevin,Slawin, Alexandra M. Z.,Smith, Andrew D.
-
supporting information
p. 5182 - 5185
(2017/11/06)
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- NH2-directed C-H alkenylation of 2-vinylanilines with vinylbenziodoxolones
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The first directing-group-mediated C-H alkenylation with alkenyl-λ3-iodanes as electrophilic alkene-transfer reagents has been developed. The application of free aromatic amines as challenging but synthetically valuable directing groups in combination with an IrIII catalyst enabled the synthesis of highly desirable 1, 3- dienes in excellent yields of up to 98% with high to perfect (Z, E) stereoselectivity. A broad substrate scope and further synthetic modifications are demonstrated.
- Boelke, Andreas,Caspers, Lucien D.,Nachtsheim, Boris J.
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supporting information
p. 5344 - 5347
(2017/11/07)
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- Palladium-catalyzed tandem C-H functionalization/cyclization strategy for the synthesis of 5-hydroxybenzofuran derivatives
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A palladium-catalyzed benzoquinone C-H functionalization/ cyclization strategy with terminal alkynes was employed for the synthesis of some biologically relevant 2, 3-disubstituted 5-hydroxybenzofuran derivatives. The benzoquinone acts as a reactant as well as an oxidant. During the process, an additional alkyne functionality can be introduced at the C3 position of the benzofuran. Base, ligand, and external oxidant are not required in this protocol.
- Ichake, Sachin S.,Konala, Ashok,Kavala, Veerababurao,Kuo, Chun-Wei,Yao, Ching-Fa
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supporting information
p. 54 - 57
(2017/11/28)
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- Copper-Catalyzed Hydrogen/Iodine Exchange in Terminal and 1-Iodoalkynes
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Detailed kinetic profiles of the copper-catalyzed exchange between the acetylenic proton and iodide of terminal and 1-iodophenylacetylenes are reported. The electronic nature of the alkynes does not influence the equilibrium of the exchange (Keq/sub
- Chung, Ryan,Vo, Anh,Hein, Jason E.
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p. 2505 - 2510
(2017/06/01)
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- Reaction discovery using acetylene gas as the chemical feedstock accelerated by the stop-flow micro-tubing reactor system
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Acetylene gas has been applied as a feedstock under transition-metal catalysis and photo-redox conditions to produce important chemicals including terminal alkynes, fulvenes, and fluorinated styrene compounds. The reaction discovery process was accelerated through the use of stop-flow micro-tubing reactors. This reactor prototype was developed by joining elements from both continuous micro-flow and conventional batch reactors, which was convenient and effective for gas/liquid reaction screening. Notably, the developed transformations were either inefficient or unsuccessful in conventional batch reactors. Its success relies on the unique advantages provided by this stop-flow micro-tubing reactor system.
- Xue, Fei,Deng, Hongping,Xue, Chengwen,Mohamed, Dara Khairunnisa Binte,Tang, Karen Yuanting,Wu, Jie
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p. 3623 - 3627
(2017/07/11)
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- Calcium carbide catalytically activated with tetra-: N -butyl ammonium fluoride for Sonogashira cross coupling reactions
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We report a novel method for the direct synthesis of mono- and bis-arylated alkynes utilizing catalytically activated CaC2 as the alkyne component. This fluoride-activated cross coupling reaction provides advantages over existing methods regarding operational simplicity, use of readily available starting materials, and low cost.
- Hosseini, Abolfazl,Pilevar, Afsaneh,Hogan, Eimear,Mogwitz, Boris,Schulze, Anne S.,Schreiner, Peter R.
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p. 6800 - 6807
(2017/08/22)
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- Synthesis of 1-arylsulfonyl-1,2,3-triazoles from (Z)-arylvinyl bromides by sequential elimination–cycloaddition reaction
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[Figure not available: see fulltext.]Efficient synthesis of 1-arylsulfonyl-1,2,3-triazoles from easily available (Z)-arylvinyl bromides is described. The sequential reaction involves elimination of HBr from (Z)-arylvinyl bromides promoted by KOH and copper-catalyzed (3+2) cycloaddition reaction between the alkyne intermediates and sulfonyl azides.
- Zhang, Wensheng,Xu, Wenjing
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p. 192 - 195
(2016/07/28)
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- Efficient synthesis of N-arylsulfonyl-1,2,3-triazoles from 1,1-dibromo-2-arylethylenes
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N-arylsulfonyl-1,2,3-triazoles were synthesized from 1,1-dibromo-2-arylethylenes via a one-pot reaction involving the Cs2CO3-mediated dehydrobromination process of the dibromoalkenes to produce alkynes followed by the Cu(I)-catalyzed Huisgen cycloaddition of the alkyne intermediates with tosyl azide.
- Xu, Wenjing,Zhang, Wensheng,Zhang, Fei
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p. 165 - 167
(2016/07/06)
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- Cleavage of the Carbon–Carbon Triple Bonds of Arylacetylenes for the Synthesis of Arylnitriles without a Metal Catalyst
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Cleavage of the carbon–carbon triple bonds of alkynes was achieved, which led to the synthesis of arylnitriles under transition-metal-free conditions. A vast range of terminal alkyne substrates underwent this reaction to provide the corresponding nitriles in moderate to good yields with good functional group tolerance.
- Lin, Yuanguang,Song, Qiuling
-
supporting information
p. 3056 - 3059
(2016/07/12)
-
- Lanthanide-Catalyzed Reversible Alkynyl Exchange by Carbon–Carbon Single-Bond Cleavage Assisted by a Secondary Amino Group
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Lanthanide-catalyzed alkynyl exchange through C?C single-bond cleavage assisted by a secondary amino group is reported. A lanthanide amido complex is proposed as a key intermediate, which undergoes unprecedented reversible β-alkynyl elimination followed by alkynyl exchange and imine reinsertion. The in situ homo- and cross-dimerization of the liberated alkyne can serve as an additional driving force to shift the metathesis equilibrium to completion. This reaction is formally complementary to conventional alkyne metathesis and allows the selective transformation of internal propargylamines into those bearing different substituents on the alkyne terminus in moderate to excellent yields under operationally simple reaction conditions.
- Shao, Yinlin,Zhang, Fangjun,Zhang, Jie,Zhou, Xigeng
-
supporting information
p. 11485 - 11489
(2016/10/24)
-
- METAL COMPLEX, AND METHOD FOR SYNTHESIS OF NITROGEN-CONTAINING ORGANIC COMPOUND USING METAL COMPLEX
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PROBLEM TO BE SOLVED: To provide a method that synthesizes a nitrogen-containing organic compound under a relatively mild condition and in a relatively simple process. SOLUTION: A method that synthesizes a nitrile compound includes a step for the reaction between an acid chloride and a complex represented by formula (1A) or formula (1B) (M1-M7 independently represent Ti, Zr, Hf, V, or the like; L1-L7 independently represent a ligand comprising a substituted/unsubstituted cyclopentadienyl derivative, a diphenylamine ligand or the like). SELECTED DRAWING: None COPYRIGHT: (C)2016,JPOandINPIT
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-
Paragraph 0094-0095
(2017/04/29)
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- Rh(III)-catalyzed cyclization reaction of azoles with alkynes: Efficient synthesis of azole-fused-pyridines
-
A Rh(III)-catalyzed cyclization of azoles with alkynes has been developed. A variety of azole-fused-pyridines were obtained in good to excellent yields and regioselectivity. Both the C5 and the C4 position of azoles were suitable for the reaction.
- Chen, Xuebing,Wu, Youzhi,Xu, Jinyi,Yao, Hequan,Lin, Aijun,Huang, Yue
-
supporting information
p. 9186 - 9189
(2015/09/07)
-
- Facile Gold-Catalyzed Heterocyclization of Terminal Alkynes and Cyanamides Leading to Substituted 2-Amino-1,3-Oxazoles
-
Facile gold-catalyzed heterocyclization based upon intermolecular trapping of the generated α-oxo gold carbenes with various cyanamides R2R3NCN (R2/R3 = Alk/Alk, -(CH2)2O(CH2)2-, Ar/Ar, Ar/H) has been developed. In most cases, 2-amino-1,3-oxazoles functionalized at the nitrogen atom as well as at the fifth position of the heterocyclic ring (12 examples) were isolated in good to moderate yields.
- Rassadin, Valentin A.,Boyarskiy, Vadim P.,Kukushkin
-
supporting information
p. 3502 - 3505
(2015/07/28)
-
- Copper-assisted nickel catalyzed ligand-free C(sp2)-O cross-coupling of vinyl halides and phenols
-
A convenient and efficient protocol has been achieved for the cross-coupling of phenols and vinyl halides by a unique Ni/Cu catalytic system for the first time, where the reaction is catalyzed by Ni and Cu is involved in the transmetalation process. This
- Kundu, Debasish,Maity, Pintu,Ranu, Brindaban C.
-
p. 1040 - 1043
(2016/10/17)
-
- Investigation of quantitative structure-reactivity relationships in the aliphatic Claisen rearrangement of bis-vinyl ethers reveals a dipolar, dissociative mechanism
-
Kinetic investigations of substituent effects in the thermal rearrangement of bis-vinyl ether substrates are reported. Findings indicate that the influence of the various substituent patterns on the rate of rearrangement in these compounds differs from that documented in the literature for the analogous [3,3]-sigmatropic rearrangement of allyl vinyl ethers. In addition, the thermochemical data collected suggests the existence of a dissociative transition state with significant dipolar character. These findings provide a unique contribution to the already extensive body of literature dedicated to mechanistic investigation of the Claisen rearrangement of aliphatic allyl vinyl ethers.
- O'Rourke, Natasha F.,Wulff, Jeremy E.
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p. 1292 - 1308
(2014/03/21)
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- Regio- and stereoselective dimerization of arylacetylenes and optical and electrochemical studies of (E)-1,3-enynes
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The N-heterocyclic carbene palladium complex (SIPr)Pd(cinnamyl)Cl [SIPr=N,N'-bis(2,4,6-trimethylphenyl)-4,5-dihydroimidazol-2-ylidene) promotes regio- and stereospecific dimerization of a variety of arylalkynes to give (E)-1,3-enynes in good to excellent yields. An efficient and practical procedure for their synthesis was developed using a biphasic aqueous alkali/heptane system. Optical and electronic properties of (E)-1,3-enynes are highly tunable. Depending on the nature of the substituents, HOMO energies vary in the range 5.3-6.0eV. (E)-1,3-Enynes can exhibit intense photoluminescence in the spectral region 350-500nm.
- Morozov, Oleg S.,Asachenko, Andrey F.,Antonov, Denis V.,Kochurov, Vitaly S.,Paraschuk, Dmitry Yu.,Nechaev, Mikhail S.
-
supporting information
p. 2671 - 2678
(2014/09/29)
-
- Pseudo five-component synthesis of 3-(hetero)arylmethyl-2,5-di(hetero)-aryl-substituted thiophenes via sonogashira-glaser cyclization sequence
-
The Sonogashira-Glaser sequence combined with a microwave-assisted cyclization is a powerful tool to synthesize unsymmetrically substituted conjugated thiophenes. A variety of 3-(hetero)arylmethyl-2,5-di(hetero)aryl-substituted thiophenes could be synthesized in moderate to excellent yields using a single Pd/Cu catalyst system. The presented method is strikingly simple to perform using commercially available starting materials. The obtained trisubstituted oligothiophene derivatives are interesting molecules for materials science.
- Klukas, Fabian,Perkampus, J?rg,Urselmann, Dominik,Müller, Thomas J. J.
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p. 3415 - 3422
(2015/02/02)
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- Aerobic oxynitration of alkynes with tBuONO and TEMPO
-
An efficient method for stereoselective nitroaminoxylation of alkyne has been reported. The reaction enjoys a broad substrate scope, good functional group tolerance, and high yields. Synthetically useful α-nitroketones can be accessed through these products in a single step.
- Dutta, Uttam,Maity, Soham,Kancherla, Rajesh,Maiti, Debabrata
-
supporting information
p. 6302 - 6305
(2015/02/19)
-
- Ti(OiPr)4/nBuLi: An attractive reagent system for [2+2+2] cyclotrimerisation reactions
-
A convenient method for the [2+2+2] cyclotrimerisation of alkynes using Ti(OiPr)4/nBuLi is presented. Homotrimerisation of arylacetylenes proceeds within minutes with excellent regioselectivity. Moreover, the intermolecular construction of ABB heterotrimers can be achieved selectively from two different alkynes with similar electronic properties. The method is also suitable for the synthesis of pyridines.
- Rassadin,Nicolas,Six
-
supporting information
p. 7666 - 7669
(2014/07/08)
-
- Synthesis of 1,2,3-triazoles from azide-derivatised aminocyclitols by catalytic diazo transfer and CuAAC click chemistry
-
CuII-catalysed diazo transfer and CuI-catalysed azide-alkyne 1,3-dipolar cycloaddition (CuAAC) "click chemistry" were used to synthesis C7N aminocyclitol-derivatised 1,2,3-triazoles. In the course of this work, the -N=N- moiety was transferred onto C7N aminocyclitols such as validamine, valienamine and valiolamine by employing imidazole-1-sulfonyl azide as the diazo transfer reagent with catalysis by CuII, ZnII and NiII, in moderate to good yields. The obtained azidocyclitols were coupled with various terminal alkynes under modified Meldal's conditions with good to excellent yields. The stereo- and regiochemistry of the products were confirmed by 2D-NMR (NOESY and HMBC). One-pot syntheses of the corresponding 1,2,3-triazoles, as safer and more efficient procedures, were also investigated and gave moderate to good yields. Copyright
- Ji, Li,Zhou, Guo-Quan,Qian, Chao,Chen, Xin-Zhi
-
supporting information
p. 3622 - 3636
(2014/06/23)
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- "quick and click" assembly of functionalised indole rings via metal-promoted cyclative tandem reactions
-
An efficient and convenient synthesis of a variety of decorated indoles using a three-component tandem metal-catalysed process is described. We propose here a new "synthetic kit" that allows for the "quick and click" assembly of indole rings using readily available, and inexpensive starting materials under environmentally friendly reaction conditions. This journal is
- Capitta, Francesca,De Luca, Lidia,Porcheddu, Andrea
-
p. 59297 - 59301
(2015/02/19)
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- Palladium nanoparticles catalyzed Sonogashira reactions for the one-pot synthesis of symmetrical and unsymmetrical diarylacetylenes
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A variety of symmetrical and unsymmetrical diarylacetylenes are synthesized by ligand-free palladium nanoparticles catalyzed copper-free and amine-free Sonogashira cross-coupling reactions between aryl iodides and trimethylsilylacetylene (TMSA) under mild reaction conditions.
- Mandali, Pavan Kumar,Chand, Dillip Kumar
-
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- Microwave-accelerated Ru-catalyzed hydrovinylation of alkynes and enynes: A straightforward approach toward 1,3-dienes and 1,3,5-trienes
-
Quick, but not dirty! Microwave heating was found to have a significant effect on the Ru-catalyzed hydrovinylations of alkynes. A broad range of different terminal alkynes were coupled to methyl acrylate within just 30min in good to excellent yields (see scheme). This new protocol was transferred to the hydrovinylation of enynes as novel coupling partners in C-H-activation chemistry giving different 1,3,5-trienes as the sole products. Copyright
- Schabel, Tobias,Plietker, Bernd
-
supporting information
p. 6938 - 6941
(2013/06/27)
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- Formal anti-markovnikov hydroamination of terminal aryl alkynes with pinacolborane and hydroxylamines via Zr/Cu sequential catalysis
-
We have explored a novel dry plasma process for the fabrication of electrodes on Nafion surfaces. Nanosized pillar structures were prepared through argon ion (Ar+) plasma treatment. The shear strengths of Au electrodes on plasma-treated Nafion surfaces were investigated. We found that the maximum shear strength (1.08 MPa) of Au-Nafion was observed under the optimal conditions (8 min, 100 W, 5 Pa, Ar+). Finally, we successfully prepared strongly bonded Au electrodes on Nafion through plasma surface treatment without using a wet plating process.
- Sakae, Ryosuke,Hirano, Koji,Satoh, Tetsuya,Miura, Masahiro
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supporting information
p. 1128 - 1130
(2013/10/22)
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- Efficient approach to 1,2-diazepines via formal diazomethylene insertion into the C-C bond of cyclobutenones
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Efficient monocyclic 1,2-diazepine formation via a tandem electrocyclization reaction of cyclobutenones with lithiodiazoacetate is demonstrated. The reaction proceeds through an oxy anion-accelerated 4π-ring opening of cyclobutene followed by an 8π-ring closure of the resultant oxy anion-substituted diazo-diene under mild conditions to furnish a 1,2-diazepine via formal diazomethylene insertion into the C-C bond of cyclobutenone.
- Sugimoto, Kenji,Hayashi, Rie,Nemoto, Hideo,Toyooka, Naoki,Matsuya, Yuji
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supporting information; experimental part
p. 3510 - 3513
(2012/07/31)
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- One-pot, two-step conversion of aldehydes to phosphonyl- and sulfonylpyrazoles using Bestmann-Ohira reagent
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A one-pot, two-step, three-component method for the conversion of commercially available aldehydes to phosphonylpyrazoles has been developed, demonstrating, for the first time, the dual reactivity of the Bestmann-Ohira reagent (BOR) in a single-pot transformation. This method, extended to the synthesis of sulfonylpyrazoles by employing BOR in the first step and a diazomethyl sulfone in the second step, is complementary, with regard to regioselectivity, to the previous methods for the synthesis of such functionalized pyrazoles.
- Kumar, Rahul,Verma, Deepti,Mobin, Shaikh M.,Namboothiri, Irishi N. N.
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supporting information; experimental part
p. 4070 - 4073
(2012/09/21)
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- Synthesis of aryl alkynyl carboxylic acids and aryl alkynes from propiolic acid and aryl halides by site selective coupling and decarboxylation
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The coupling of propiolic acid with aryl iodides afforded the aryl alkynyl carboxylic acids and aryl alkynes in generally good yields. Aryl alkynyl carboxylic acids were obtained when the reaction was performed in the presence of Pd(PPh3)2Cl2 (2.5 mol %), dppb (5.0 mol %) and DBU (5 equiv) at 50°C. For the synthesis of the terminal aryl alkynes, the reaction was conducted in the presence of Pd(PPh3) 2Cl2 (2.5 mol %), dppb (5.0 mol %), DBU (5.0 equiv), and Cu(acac)2 (10 mol %) at 25°C for 5 h, and further reacted at 60°C for 6 h.
- Park, Kyungho,Palani, Thiruvengadam,Pyo, Ayoung,Lee, Sunwoo
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experimental part
p. 733 - 737
(2012/03/08)
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- Simple and practical one-step synthesis of new 1,3-dienic δ-sultones from terminal alkynes and some synthetic applications of these compounds
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1,3-Dienic δ-sultones 4,6-diaryl-[1,2]oxathiine 2,2-dioxides were synthesized via a one-step reaction of arylalkynes with dioxane sulfotrioxide. The reactivity of various alkynes in this reaction was investigated. The resulting sultones were brominated with Br2 or N-bromosuccinimide regioselectively to sulfur and subsequently coupled with phenylacetylene using Sonogashira conditions.
- Gaitzsch, Jens,Rogachev, Victor,Metz, Peter,Filimonov, Victor D.,Zahel, Martin,Kataeva, Olga
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experimental part
p. 3 - 16
(2011/12/05)
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- Cs2CO3-mediated synthesis of terminal alkynes from 1,1-dibromo-1-alkenes
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An unprecedented route to prepare terminal alkynes from 1,1-dibromo-1-alkenes mediated by Cs2CO3 was proven. 1,1-Dibromo-1-alkenes bearing various functional groups were efficiently converted to corresponding terminal alkynes in moderate to excellent yields.
- Zhao, Ming,Kuang, Chunxiang,Yang, Qing,Cheng, Xuezhi
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scheme or table
p. 992 - 994
(2011/03/22)
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- Convenient synthesis of terminal alkynes from anti-3-aryl-2,3- dibromopropanoic acids using a K2CO3/DMSO system
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A convenient, efficient, and generally applicable method was developed for the synthesis of terminal alkynes from anti-3-aryl-2,3-dibromopropanoic acids in the presence of DMSO and K2CO3.
- Cheng, Xuezhi,Jia, Jun,Kuang, Chunxiang
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experimental part
p. 2350 - 2354
(2012/02/03)
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- BF3×OEt2-catalyzed reaction of donor-acceptor cyclobutanes with terminal alkynes: Single-step access to 2,3-dihydrooxepines
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In the presence of BF3OEt2 cyclobutane-1,1-diesters undergo a reaction with terminal alkynes to quickly access dihydro-oxepines. Georg Thieme Verlag Stuttgart · New York.
- MacHin, Ben P.,Pagenkopf, Brian L.
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supporting information; experimental part
p. 2799 - 2802
(2012/01/11)
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- Synthesis and antiplasmodial activity of new indolone N-Oxide derivatives
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A series of 66 new indolone-N-oxide derivatives was synthesized with three different methods. Compounds were evaluated for in vitro activity against CQ-sensitive (3D7), CQ-resistant (FcB1), and CQ and pyrimethamine cross-resistant (K1) strains of Plasmodium falciparum (P.f.), aswell as for cytotoxic concentration (CC50) on MCF7 and KB human tumor cell lines. Compound 26 (5-methoxy-indolone-N-oxide analogue) had the most potent antiplasmodial activity in vitro (50 MCF7/IC50 FcB1: 14623; CC50 KB/IC50 3D7: 198823). In in vivo experiments, compound 1 (dioxymethylene derivatives of the indolone-N-oxide) showed the best antiplasmodial activity against Plasmodium berghei, 62% inhibition of the parasitaemia at 30 mg/kg/day. 2009 American Chemical Society.
- Nepveu, Fran?oise,Kim, Sothea,Boyer, Jeremie,Chatriant, Olivier,Ibrahim, Hany,Reybier, Karine,Monje, Marie-Carmen,Chevalley, Severine,Perio, Pierre,Lajoie, Barbora H.,Bouajila, Jalloul,Deharo, Eric,Sauvain, Michel,Tahar, Rachida,Basco, Leonardo,Pantaleo, Antonella,Turini, Francesco,Arese, Paolo,Valentin, Alexis,Thompson, Eloise,Vivas, Livia,Petit, Serge,Nallet, Jean-Pierre
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scheme or table
p. 699 - 714
(2010/07/09)
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- Gold-catalyzed oxidative ring expansions and ring cleavages of alkynylcyclopropanes by intermolecular reactions oxidized by diphenylsulfoxide
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A golden opportunity: A novel gold-catalyzed oxidative ring-expansion of unactivated cyclopropylalkynes using Ph2SO has been developed (see scheme). For substrates bearing a donor group at the cyclopropane ring, preliminary results reveal a distinct cleavage of the cyclopropane unit; such a ring cleavage is further applicable to the synthesis of 2H-pyrans. L=P(tBu) 2(o-biphenyl), Tf=triflate. Copyright
- Li, Chia-Wen,Pati, Kamalkishore,Lin, Guan-You,Sohel, Shariar Md. Abu,Hung, Hsiao-Hua,Liu, Rai-Shung
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supporting information; experimental part
p. 9891 - 9894
(2011/02/24)
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- The application of (Z)-3-aryl-3-haloenoic acids to the synthesis of (Z)-5-benzylidene-4-arylpyrrol-2(5H)-ones
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Studies directed at the synthesis of (Z)-5-benzylidene-4-arylpyrrol-2(5H)- ones from (Z)-3-aryl-3-haloenoic acids are described. The successful strategy relies on the preparation of (Z)-3-aryl-3-haloenoic acids from acetophenones through the corresponding
- Gupton, John T.,Telang, Nakul,Banner, Edith J.,Kluball, Emily J.,Hall, Kayleigh E.,Finzel, Kara L.,Jia, Xin,Bates, Spencer R.,Welden, R. Scott,Giglio, Benjamin C.,Eaton, James E.,Barelli, Peter J.,Firich, Lauren T.,Stafford, John A.,Coppock, Matthew B.,Worrall, Eric F.,Kanters, Rene P.F.,Keertikar, Kerry,Osterman, Rebecca
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experimental part
p. 9113 - 9122
(2011/01/12)
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- One-pot procedure for the synthesis of unsymmetrical diarylalkynes
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Unsymmetrical diarylalkynes are accessible by a one-pot procedure from two different aryl halides and (trimethylsilyl)acetylene. The three-component coupling is initialized by a Pd/Cu-catalyzed Sonogashira coupling of an aryl halide with (trimethylsilyl)a
- Severin, Rene,Reimer, Jessica,Doye, Sven
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supporting information; experimental part
p. 3518 - 3521
(2010/07/17)
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