- Oxophosphonium-Alkyne Cycloaddition Reactions: Reversible Formation of 1,2-Oxaphosphetes and Six-membered Phosphorus Heterocycles
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While the metathesis reaction between alkynes and carbonyl compounds is an important tool in organic synthesis, the reactivity of alkynes with isoelectronic main-group R2E≠O compounds is unexplored. Herein, we show that oxophosphonium ions, which are the
- L?we, Pawel,Feldt, Milica,Wünsche, Marius A.,Wilm, Lukas F.B.,Dielmann, Fabian
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- Nickel-Catalyzed Annulation of Aliphatic Amides with Alkynyla silanes: An Expeditious Approach to Five-Membered Lactams
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An expeditious approach for the synthesis of diverse five-membered lactams through nickel-catalyzed annulation of the C(sp 3)-H bonds of aliphatic amides with alkynylsilanes assisted by an 8-Aminoquinolinyl directing group is reported, delivering the corresponding lactam derivatives in moderate to high yields. It is worth noting that alkynylsilanes are employed for the first time as coupling partners in the transition-metal-catalyzed functionalization of C(sp 3)-H bonds of aliphatic amides. Equimolar amounts of alkynylsilanes and aliphatic amides are utilized, which greatly increases the efficiency of this protocol.
- Gao, Fei,Lin, Cong,Lin, Jingyi,Shen, Liang,Teng, Qiuxun,Xu, Yiqing
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- Tributylstannyl radical-catalyzed reaction of 1,2,3-selenadiazoles with olefins or dienes
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It was found that the reaction of 1,2,3-selenadiazoles derived from cyclic ketones with olefins or dienes was markedly promoted by a catalytic amount of tributylstannyl radical, which was generated in situ from tributylstannyl hydride or allyltributylstannane and AIBN, to give the corresponding dihydroselenophenes in moderate to good yields. In contrast, when 1,2,3-selenadiazoles prepared from linear and aromatic ketones were used as substrates, the same reaction did not take place, and alkynes were formed as the sole product.
- Nishiyama, Yutaka,Hada, Yasunobu,Anjiki, Masahiro,Miyake, Kazuya,Hanita, Sakiko,Sonoda, Noboru
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- Alkynylic SRN1 Reaction: Feasible or Not?
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A comparison of the relative propensity of aryl-, vinyl-, and ethynyl-halides towards a SRN1 reaction is made possible by an investigation of some nucleophilic reactions with bromophenylethyne.
- Galli, Carlo,Gentili, Patrizia
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- Experimental and computational study of the ultraviolet photolysis of vinylacetylene. Part II
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The ultraviolet photochemistry of vinylacetylene (C4H 4) was studied under temperature and pressure conditions similar to Titan's atmosphere by exciting the molecule in a constrained expansion that opens into the ion source region of a time-of-flight mass spectrometer. The primary dissociation products detected by vacuum-ultraviolet ionization were found to be C4H3 and C4H2, in a ratio of 3-10: 1. Subsequent reaction of the C4H3 radicals with the parent C4H4 produced two major secondary products: C8H6 and C6H4. The former was spectroscopically identified as phenylacetylene, confirming that photochemical reactions of C4H4 can produce aromatic molecules. The primary dissociation reaction was also studied computationally. The results were consistent with the experimental findings for C 4H2 and C4H3. However, the major product is C2H2, which is undetected by 118 nm photoionization in the present experiment but should account for roughly two-thirds of the products. Simulations were also performed to confirm that the present experiment accurately represents the 220 nm photochemistry of vinylacetylene at the temperature and pressure of Titan's atmosphere, with a product yield of C2H2: C4H2: C 4H3 of 66: 7: 27. Accounting for the wavelength dependent solar flux on Titan, the estimated absorption cross section of vinylacetylene in the ultraviolet, and the slightly wavelength dependent product distribution, the overall product yield predicted by the simulations for ultraviolet photolysis of vinylacetylene on Titan is C2H2: C 4H2: C4H3 = 65: 8: 27. Finally, a simulation was performed under conditions of a shock tube experiment to examine the differences between thermal and photochemical dissociation. The product yield of this simulation was C2H2: C4H 2: C4H3 = 61: 1: 38. the Owner Societies 2006.
- Stearns, Jaime A.,Zwier, Timothy S.,Kraka, Elfriede,Cremer, Dieter
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- Formation of Metal Acetylides via Complexes of Molecular Hydrogen
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Terminal acetylenes react with to form metal acetylides and diacetylides; the crystal structure of trans-Fe(CCPh)2(dmpe)2 shows that the seven atoms of the C-CC-Fe-CC-C grouping are colinear and
- Field, Leslie D.,George, Adrian V.,Hambley, Trevor W.,Malouf, Elizabeth Y.,Young, David J.
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- Transition-metal-free chemo- and regioselective vinylation of azaallyls
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Direct C(sp 3)-C(sp 2) bond formation under transition-metal-free conditions offers an atom-economical, inexpensive and environmentally benign alternative to traditional transition-metal-catalysed cross-coupling reactions. A new chemo- and regioselective coupling protocol between 3-aryl-substituted-1,1-diphenyl-2-azaallyl derivatives and vinyl bromides has been developed. This is the first transition-metal-free cross-coupling of azaallyls with vinyl bromide electrophiles and delivers allylic amines in excellent yields (up to 99%). This relatively simple and mild protocol offers a direct and practical strategy for the synthesis of high-value allylic amine building blocks that does not require the use of transition metals, special initiators or photoredox catalysts. Radical clock experiments, electron paramagnetic resonance studies and density functional theory calculations point to an unprecedented substrate-dependent coupling mechanism. Furthermore, an electron paramagnetic resonance signal was observed when the N-benzyl benzophenone ketimine was subjected to silylamide base, supporting the formation of radical species upon deprotonation. The unique mechanisms outlined herein could pave the way for new approaches to transition-metal-free C-C bond formations.
- Li, Minyan,Gutierrez, Osvaldo,Berritt, Simon,Pascual-Escudero, Ana,Ye?l?imen, Ahmet,Yang, Xiaodong,Adrio, Javier,Huang, Georgia,Nakamaru-Ogiso, Eiko,Kozlowski, Marisa C.,Walsh, Patrick J.
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- In Situ Shell-Isolated Nanoparticle-Enhanced Raman Spectroscopy to Unravel Sequential Hydrogenation of Phenylacetylene over Platinum Nanoparticles
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Shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS) is quickly developing into a powerful characterization tool in heterogeneous catalysis. In this work, we employ Pt catalysts supported on Au@SiO2 shell-isolated nanoparticles to study hydrogenation reactions. First, we demonstrate the facile preparation of Pt/Au@SiO2 and its characterization by using adsorption of CO as probe molecule. Next, we use the adsorption and hydrogenation of phenylacetylene as a model reaction for the interaction of triple bonds and aromatic rings with catalytic Pt surfaces. We show that the applicability of SHINERS is not limited to inherently gaseous compounds, thereby expanding the applicability of the technique to more complex systems. Furthermore, by using nonparticipating side groups as labels, we observe the sequential hydrogenation of phenylacetylene into styrene and ultimately ethylbenzene upon reaction with H2. Upon the absence of H2, the reverse reaction takes place with those molecules still adsorbed onto the catalyst surface, which allowed a more detailed understanding of the reaction mechanism and the assignment of Raman peaks. This strengthens the position of SHINERS as an easily applicable surface sensitive technique that can be used to study a wide variety of chemical reactions in the field of heterogeneous catalysis.
- Wondergem, Caterina S.,Hartman, Thomas,Weckhuysen, Bert M.
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- 1-Methoxycarbonylpyrrolizin-3-one and related compounds
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Flash vacuum pyrolysis (FVP) of dimethyl E- or Z-pyrrol-2-ylbut-2-enedioate 5 at 700 °C gave 1-methoxycarbonylpyrrolizin-3-one 1. The sequence involves E- to Z-isomerisation (if necessary), elimination of methanol and cyclisation; the elimination step is
- Despinoy, Xavier L. M.,McNab, Hamish
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- Conversion of Allyl Alk-2-ynoates to Alk-2-ynoic Acids Using Morpholine and Palladium(0)-Bis(diphenylphosphino)alkane Catalyst; Synthesis of 2,2,3,3-Tetradehydro PGE1
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Allyl alk-2-ynoates can be readily converted into alk-2-ynoic acids by the reaction with morpholine in the presence of a palladium-diphenylphosphinopropane catalyst, thus providing the chemical deprotection method of allyl ester of 2,2,3,3-tetradehydro PGE1.
- Okamoto, Sentaro,Ono, Naoya,Tani, Kousuke,Yoshida, Yukio,Sato, Fumie
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- Ground-State Chemical Reactivity under Vibrational Coupling to the Vacuum Electromagnetic Field
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The ground-state deprotection of a simple alkynylsilane is studied under vibrational strong coupling to the zero-point fluctuations, or vacuum electromagnetic field, of a resonant IR microfluidic cavity. The reaction rate decreased by a factor of up to 5.5 when the Si?C vibrational stretching modes of the reactant were strongly coupled. The relative change in the reaction rate under strong coupling depends on the Rabi splitting energy. Product analysis by GC-MS confirmed the kinetic results. Temperature dependence shows that the activation enthalpy and entropy change significantly, suggesting that the transition state is modified from an associative to a dissociative type. These findings show that vibrational strong coupling provides a powerful approach for modifying and controlling chemical landscapes and for understanding reaction mechanisms.
- Thomas, Anoop,George, Jino,Shalabney, Atef,Dryzhakov, Marian,Varma, Sreejith J.,Moran, Joseph,Chervy, Thibault,Zhong, Xiaolan,Devaux, Elo?se,Genet, Cyriaque,Hutchison, James A.,Ebbesen, Thomas W.
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- THERMAL DECOMPOSITION OF (η-CYCLOPENTADIENYL)TRICARBONYL(?-PHENYLETHYNYL)MOLYBDENUM AND THE MOLECULAR STRUCTURE OF A MOLYBDENUM BINUCLEAR COMPLEX WITH A BRIDGING 1,4-DIPHENYLBUTADIYNE LIGAND 2(μ-1,2-η-C6H5CC-CCC6H5)
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Thermolysis of C5H5(CO)3MoCCC6H5 (I) in octane at 110-115 deg C results in the formation of 2(μ-1,2-η-C6H5CC-CCC6H5) (II).The structure of II was determined by X-ray analysis.The reaction scheme is discussed.
- Ustynyuk, N. A.,Vinogradova, V. N.,Korneva, V. N.,Kravtsov, D. N.,Andrianov, V. G.,Struchkov, Yu. T.
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- Ruthenium-Dihydrogen Complexes via C-H Cleavage in Alk-1-ynes. Crystal Structure of CPh)(dippe)2>
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The reaction of the monohydride complex + with alk-1-ynes yields the dihydrogen complexes CR)(dippe)2>+ CPh)(dippe)2> has been determined, a
- Tenorio, Manuel Jimenez,Puerta, M. Carmen,Valerga, Pedro
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- A New Insight into the SRN1 Vinylic Substitution
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Evidence is gathered on vinylic nucleophilic substitutions that suggests the occurrence of an ionic elimination-addition route along with the originally proposed SRN1 route.
- Galli, Carlo,Gentili, Patrizia
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- Activation of C-H bonds in acetylene and terminal alkynes by rhodium(I) species. Crystal structure of cis-(ethynyl)hydrie BPh4.1.5C4H8O (NP3 = N(CH2CH2PPh2)3)
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The 16-electron fragment (NP3)Rh+ inserts in a highly stereospecific manner across C-H bonds from acetylene and 1-alkynes to give the octahedral cis-(alkynyl)hydrides BPh4 (R = H, Ph, COOEt).The structure of the cis-(ethynyl)hydride BPh4.1.5 THF has been established by X-ray diffraction.The trigonal bipyramidal rhodium(I) complex , reacts with terminal alkynes to give H2 and the neutral ?-acetylides (R = Ph, COOEt).These undergo metathesis between terminal alkynes and the ?-acetylide ligand through a mechanism involving consecutive breaking and making of C-H bonds.
- Bianchini, Claudio,Mealli, Carlo,Peruzzini, Maurizio,Vizza, Francesco,Zanobini, Fabrizio
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- Method for synthesizing high-purity MDPES raw material phenyl acetylene in one step
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The invention relates to the technical field of biological medicines, in particular to a method for synthesizing high-purity MDPES raw material phenyl acetylene in one step. The method comprises the following steps: in a solvent, uniformly stirring and mixing 1,2-dibromoethyl benzene and alkali, heating to 40-160 DEG C, reacting completely, filtering to remove bromide, and carrying out filtrate distillation separation, wherein one group of isolate is a recyclable solvent, the other group of isolate is product phenyl acetylene, and the GC purity is greater than 98%; the solvent is mixed and stirred, the temperature is raised to 40-160 DEG C after stirring to react completely, bromide is removed through filtration, GC purity is greatly improved through filtrate distillation separation, the GC purity is higher than 98%, the phenyl acetylene synthesis step is shortened, the phenyl acetylene raw material utilization rate is high, the solvent can be recycled, and the product yield is high; moreover, the product is higher in purity and more environmentally friendly, so that the industrial mass production requirement is better met, and the method is more suitable for popularization and application.
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Paragraph 0037-0048
(2021/03/11)
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- Green method for solvent-free synthesis of MDPES raw material phenylacetylene
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The invention relates to a novel green method for solvent-free synthesis of MDPES raw material phenylacetylene, which comprises the following steps: uniformly mixing and stirring 1,2-dibromoethyl benzene, alkali and a catalyst EB-D, conducting heating to 40-160 DEG C, condcuting complete reacting, conducting filtering to remove bromide, conducting filtering to separate the mixture of solid and liquid, conducting filtering again when the filtrate is still turbid after filtration, and distilling the filtrate to obtain the product, namely, phenylacetylene. The product detection purity is larger than 98%. The method overcomes the defects of many steps, complex post-treatment, expensive raw materials, high safety risk, high environmental protection pressure, low product purity and the like caused by using bromine, carbon tetrachloride, methanol, metal sodium, sodium hydride, lithium amide, palladium chloride and other raw materials in the traditional process. The specific synthetic route is as follows: under the solvent-free condition, 1,2-dibromoethyl benzene is used as a starting raw material, alkali is used as a dehalogenating agent, a catalyst EB-D is added, a one-step dehalogenation reaction is carried out at 40-160 DEG C until complete dehalogenation reaction is realized, and filtering and distillation are carried out to obtain the MDPES raw material phenylacetylene.
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Paragraph 0034-0041
(2021/04/07)
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- Dimeric Indenofluorene-Extended Tetrathiafulvalene Motif for Enhanced Intramolecular Complexation
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Tetrathiafulvalene (TTF) is a redox-active compound, which reversibly undergoes two one-electron oxidations to give stable species. Several features of TTF, such as redox and optical properties as well as geometry and self-associating nature, can be tuned by extension of the conjugated system with an aromatic linker such as an indenofluorene (IF) moiety. In this work we present the synthesis of a novel dimeric scaffold of IF-extended TTF (IF-TTF) in which the units are linked by a rigid 1,4-bis(2-ethynylphenyl)buta-1,3-diyne moiety. 1H-NMR spectroscopic studies reveal that the scaffold is highly prone to form intramolecular IF-TTF dimer complexes even in the neutral form, and stable radical cation species were formed in solution upon chemical oxidation with tris(4-bromophenyl)ammoniumyl hexachloroantimonate (‘magic blue’). Electrocrystallization of the rigid scaffold yielded a semi-conducting material, which proved to be stable at ambient temperature and air.
- Brol?s, Line,Kilde, Martin Dr?hse,Brock-Nannestad, Theis,Nielsen, Mogens Br?ndsted
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p. 3537 - 3544
(2021/06/18)
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- Ru-catalyzed (E)-specific ortho-C-H alkenylation of arenecarboxylic acids by coupling with alkenyl bromides
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In the presence of [p-cymene)RuCl2]2, (E)-configured alkenyl bromides couple with aromatic carboxylates to form ortho-vinylbenzoic acids. This C-H vinylation proceeds in high yields without any activating phosphine ligands and has an excellent functional group tolerance. Starting from commonly available (E/Z)-mixtures of alkenyl bromides, (E)-configured vinyl arenes or dienes are formed exclusively. Mechanistic studies show that this selectivity is achieved because the (E)-configured alkenyl bromides undergo a smooth coupling, whereas the (Z)-isomers are rapidly eliminated with the formation of alkynes.
- Belitz, Florian,Goo?en, Lukas J.,Hu, Zhiyong,Papp, Florian,Zhang, Guodong
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supporting information
p. 3541 - 3545
(2021/05/31)
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- Synthesis of 1,3-Diynes Using Calcium Carbide as an Alkyne Source
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A simple method for the synthesis of 1,3-diynes from iodoarenes using calcium carbide as an alkyne source and air as an oxidant is described. A series of 1,4-diarylbuta-1,3-diynes were efficiently synthesized by this strategy. The salient features of this protocol are the use of inexpensive and easy-to-handle alkyne source, broad substrate scope, open-air condition, and simple operation procedure.
- Liu, Zhenrong,Li, Zheng
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p. 302 - 308
(2020/12/11)
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- A trinuclear chromium(iii) chlorocarbyne
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Reduction of CCl4 by CrCl2 in THF afforded a trinuclear chromium(iii) carbyne [CrCl(thf)2]3(μ3-CCl)(μ-Cl)3. The chlorocarbyne complex reacted with aldehydes to afford chloroallylic alcohols and terminal alkynes. The mechanistic study proposed two competitive pathways via an α-chlorovinyl intermediate.
- Kurogi, Takashi,Irifune, Keiichi,Enoki, Takahiro,Takai, Kazuhiko
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supporting information
p. 5199 - 5202
(2021/05/31)
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- Using Postsynthetic X-Type Ligand Exchange to Enhance CO2Adsorption in Metal-Organic Frameworks with Kuratowski-Type Building Units
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Postsynthetic modification methods have emerged as indispensable tools for tuning the properties and reactivity of metal-organic frameworks (MOFs). In particular, postsynthetic X-type ligand exchange (PXLE) at metal building units has gained increasing attention as a means of immobilizing guest species, modulating the reactivity of framework metal ions, and introducing new functional groups. The reaction of a Zn-OH functionalized analogue of CFA-1 (1-OH, Zn(ZnOH)4(bibta)3, where bibta2- = 5,5′-bibenzotriazolate) with organic substrates containing mildly acidic E-H groups (E = C, O, N) results in the formation of Zn-E species and water as a byproduct. This Br?nsted acid-base PXLE reaction is compatible with substrates with pKa(DMSO) values as high as 30 and offers a rapid and convenient means of introducing new functional groups at Kuratwoski-type metal nodes. Gas adsorption and diffuse reflectance infrared Fourier transform spectroscopy experiments reveal that the anilide-exchanged MOFs 1-NHPh0.9 and 1-NHPh2.5 exhibit enhanced low-pressure CO2 adsorption compared to 1-OH as a result of a Zn-NHPh + CO2 ? Zn-O2CNHPh chemisorption mechanism. The MFU-4l analogue 2-NHPh ([Zn5(OH)2.1(NHPh)1.9(btdd)3], where btdd2- = bis(1,2,3-triazolo)dibenzodioxin), shows a similar improvement in CO2 adsorption in comparison to the parent MOF containing only Zn-OH groups.
- Bien, Caitlin E.,Cai, Zhongzheng,Wade, Casey R.
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p. 11784 - 11794
(2021/07/26)
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- Direct Evidence on the Mechanism of Methane Conversion under Non-oxidative Conditions over Iron-modified Silica: The Role of Propargyl Radicals Unveiled
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Radical-mediated gas-phase reactions play an important role in the conversion of methane under non-oxidative conditions into olefins and aromatics over iron-modified silica catalysts. Herein, we use operando photoelectron photoion coincidence spectroscopy to disentangle the elusive C2+ radical intermediates participating in the complex gas-phase reaction network. Our experiments pinpoint different C2-C5 radical species that allow for a stepwise growth of the hydrocarbon chains. Propargyl radicals (H2C?C≡C?H) are identified as essential precursors for the formation of aromatics, which then contribute to the formation of heavier hydrocarbon products via hydrogen abstraction–acetylene addition routes (HACA mechanism). These results provide comprehensive mechanistic insights that are relevant for the development of methane valorization processes.
- ?ot, Petr,Hemberger, Patrick,Pan, Zeyou,Paunovi?, Vladimir,Puente-Urbina, Allen,van Bokhoven, Jeroen Anton
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supporting information
p. 24002 - 24007
(2021/10/01)
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- 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
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supporting information
p. 1223 - 1230
(2020/04/15)
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- Fe-Catalyzed Selective Cyclopropanation of Enynes under Photochemical or Thermal Conditions
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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
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supporting information
p. 340 - 344
(2020/01/11)
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- Transition-metal-free variant of Glaser- and Cadiot-Chodkiewicz-type Coupling: Benign access to diverse 1,3-diynes and related molecules
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Efficient and transition-metal-free transformations towards the synthesis of 1,3-diynes have been described from their corresponding terminal acetylenes or 1,1-dibromo-1-alkenes. The efficiency of molecular iodine as catalyst in aqueous medium, driven the transformation to afford 1,3-diynes in moderate to good yields. The developed reaction conditions revealed appreciable functional group tolerance in aqueous medium. Further, the scope of the transition-metal-free approach for the synthesis of 1,3-enynes has been investigated using terminal alkynes as easy available precursors.
- Kaldhi, Dhananjaya,Vodnala, Nagaraju,Gujjarappa, Raghuram,Kabi, Arup K.,Nayak, Subhashree,Malakar, Chandi C.
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- In Situ Generation of Alkynylzinc and Its Subsequent Negishi Reaction in a Flow Reactor
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A highly efficient and convenient Negishi cross-coupling reaction has been developed for the synthesis of unsymmetrical alkynes and enynes in a continuous-flow process. The reaction proceeds through an in situ generated alkynylzinc reagent by the reaction of lithium acetylide with zinc halide at room temperature followed by a cross-coupling reaction with aryl or vinyl iodides. The notable features of this work compared to the conventional benchtop method are mild reaction conditions, good to excellent yields, broad functional-group compatibility, short residence time (73 sec) and especially desilylation of TMS group with the residence time of only 10.5 sec.
- Kandasamy, Mohanraj,Huang, Yu- Hsuan,Ganesan, Balaji,Senadi, Gopal Chandru,Lin, Wei-Yu
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supporting information
p. 4349 - 4356
(2019/07/03)
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- Transition-Metal-Free α-Vinylation of Enolizable Ketones with β-Bromostyrenes
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An α-vinylation of enolizable ketones has been developed by using β-bromostyrenes and a KOtBu/NMP system. β,γ-Unsaturated ketones of E configuration were obtained in excellent yield and selectivity. Further synthetic possibilities are highlighted by one-pot functionalization via trapping of intermediate dienolates with alkyl, allyl, benzyl, and propargyl halides to generate quaternary centers. The reported transformation is believed to involve phenylacetylene and propargylic alcohol derivatives.
- Zaid, Yassir,Mboyi, Clève Dionel,Drapeau, Martin Pichette,Radal, Léa,Chahdi, Fouad Ouazzani,Rodi, Youssef Kandri,Ollevier, Thierry,Taillefer, Marc
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p. 1564 - 1568
(2019/03/11)
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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
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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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- Palladium-Catalyzed One-Pot Four-Component Synthesis of β-Cyano-α,β-unsaturated Ketones Using Calcium Carbide as an Acetylene Source and Potassium Hexacyanoferrate(II) as an Eco-Friendly Cyanide Source
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Palladium-catalyzed one-pot four-component synthesis of β-cyano-α,β-unsaturated ketones by the reactions of aryl halides, calcium carbide, potassium hexacyanoferrate(II) and aroyl chlorides is described. The salient features of this protocol are the direct use of easy-to-handle acetylene source and eco-friendly cyanide source, wide scope of substrates with good functional group tolerance, and simple work-up procedure. (Figure presented.).
- Lu, Hao,Li, Zheng
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p. 4474 - 4482
(2019/08/20)
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- The gold-catalyzed formal hydration, decarboxylation, and [4+2] cycloaddition of alkyne derivatives featuring L2/Z-type diphosphinoborane ligands
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The catalytic formal hydration of alkynes and decarbox-ylation of alkynoic acid were developed using a Au catalyst featuring a Z-ligand. Furthermore, the intramolecular [4+2] cycloaddition of the alkynoic acid-alkene derivative for the formation of the oxabicyclo[4.4.0] skeleton also proceeded.
- Matsumoto, Chiaki,Yamada, Masayuki,Dong, Xun,Mukai, Chisato,Inagaki, Fuyuhiko
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p. 1321 - 1323
(2018/10/15)
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- Controlled photorelease of alkynoic acids and their decarboxylative deprotection for copper-catalyzed azide/alkyne cycloaddition
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A controlled photorelease of alkynoic acids from the meso-methyl BODIPY photoremovable protecting group facilitates their subsequent efficient decarboxylation to give terminal alkynes for a CuI-catalyzed azide/alkyne cycloaddition. The quantum efficiencies of the photochemical step and the kinetics of the click reaction step are reported.
- Vohradská, Nikoleta,Sánchez-Carnerero, Esther M.,Pastierik, Tomá?,Mazal, Ctibor,Klán, Petr
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supporting information
p. 5558 - 5561
(2018/06/04)
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- Release of Terminal Alkynes via Tandem Photodeprotection and Decarboxylation of o -Nitrobenzyl Arylpropiolates in a Flow Microchannel Reactor
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Photocleavable protecting groups (PPGs) offer a complementary protection paradigm compared to traditional protection groups. Herein, an o-nitrobenzyl (NB) PPG was employed to protect a variety of arylpropiolic acids. Upon a cascade of light-triggered photodeprotection in a microchannel reactor (residence times of 100-500 s), followed by Cu-catalyzed decarboxylation at 60 °C, the NB-protected arylpropiolic acid afforded a terminal alkyne. This terminal alkyne was further reacted in situ with an azide via click chemistry to yield a 1,2,3-triazole in a one-pot reaction. Furthermore, the effect of different substituents (methyl, vinyl, allyl, and phenyl) at the benzylic position on the rate of photodeprotection was studied. The quantum yields of photolysis for the benzylic-substituted esters were determined to be as high as 0.45 compared to the unsubstituted ester with a 0.08 quantum yield of photolysis.
- Tebikachew, Behabitu Ergette,B?rjesson, Karl,Kann, Nina,Moth-Poulsen, Kasper
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p. 1178 - 1185
(2018/04/23)
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- Automatic regulation and control type photoelectric conversion molecule and preparation method thereof
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The invention provides an automatic regulation and control type photoelectric conversion molecule. The automatic regulation and control type photoelectric conversion molecule comprises an optical switch molecule, an electron donor which is connected to one end of the optical switch molecule through a covalent bond and an electron acceptor which is connected to the other end of the optical switch molecule through an acetylene group, wherein the optical switch molecule is a group comprising a photochromic compound; the electron donor is a group capable of providing electrons; the electron acceptor is a group which has an electron accepting capability and has electronegativity stronger than that of the electron donor and the optical switch molecule. The automatic regulation and control type photoelectric conversion molecule can be used for efficiently collecting solar energy and converting the solar energy into excitation-state electron energy. The automatic regulation and control type photoelectric conversion molecule is of an open structure at an initial state; electrons are transferred to the acceptor from the donor and an optical switch under light illumination; the optical switchis triggered to be automatically closed and charge flowing in the molecule is stopped; excited electrons cannot reflow and compound, so that efficient separation of charges in an organic molecule system is realized; the closed optical switch absorbs light and is converted back to an opening state after the excited electrons are consumed, so that automatic circulation is realized.
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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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- Palladium-metalated porous organic polymers as recyclable catalysts for chemoselective decarbonylation of aldehydes
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A novel palladium nanoparticle (NP)-metalated porous organic ligand (Pd NPs/POL-xantphos) has been prepared for the chemoselective decarbonylation of aldehydes. This heterogenous catalyst not only has excellent catalytic activity and chemoselectivity, but also holds high activity after 10 runs of reuse. The effective usage of this method is demonstrated through the synthesis of biofuels such as furfuryl alcohol (FFA) via the highly chemoselective decarbonylation of biomass-derived 5-hydroxy-methylfurfural (HMF) with a TON up to 1540. More importantly, 9-fluorenone could be obtained in one step through the decarbonylation of 2-bromobenzaldehyde by using this heterogeneous catalyst.
- Li, Wen-Hao,Li, Cun-Yao,Li, Yan,Tang, Hai-Tao,Wang, Heng-Shan,Pan, Ying-Ming,Ding, Yun-Jie
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supporting information
p. 8446 - 8449
(2018/08/28)
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- Copper-NHC-Mediated Semihydrogenation and Hydroboration of Alkynes: Enhanced Catalytic Activity Using Ring-Expanded Carbenes
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A series of two-coordinate copper tert-butoxide complexes bearing five-, six-, and seven-membered ring N-heterocyclic carbenes, prepared by protonolysis of (NHC)CuMes with tBuOH, have been used as catalytic precursors in the semihydrogenation of alkynes with silanes/tBuOH and the hydroboration of alkynes with HBPin. Both processes proceed with high regioselectivity and show enhancements with six- and seven-membered ring carbenes.
- Hall, Jonathan W.,Unson, Darcy M. L.,Brunel, Paul,Collins, Lee R.,Cybulski, Mateusz K.,Mahon, Mary F.,Whittlesey, Michael K.
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supporting information
p. 3102 - 3110
(2018/09/12)
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- SO2F2-Mediated Oxidative Dehydrogenation and Dehydration of Alcohols to Alkynes
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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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p. 17666 - 17673
(2019/01/04)
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- A Schiff base-modified silver catalyst for efficient fixation of CO2 as carboxylic acid at ambient pressure
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The fixation of CO2 as a carboxylic acid is a significant reaction for C-C bond formation in organic synthesis. So far, besides C-H carboxylations using stoichiometric amounts of metals or organometallic reagents, great efforts have been devoted to develop new heterogeneous catalyst, while the catalytic performance of supported metal catalysts is not satisfactory. Herein, a Schiff base-modified silver catalyst was developed for the direct carboxylation of terminal alkynes with CO2, enabling an efficient and green synthesis of valuable alkynyl carboxylic acids. The reaction can smoothly proceed under atmospheric pressure and low temperature (60 °C) conditions. Moreover, a silver-based catalyst, which was prepared by an in situ reduction route, can be easily prepared, recovered, and reused five times without significant loss of activity due to the stability promoted by the Schiff-base on the support surface. In addition, the markedly negative influence of H2O and solvent effect on this reaction system has also been discussed.
- Wu, Zhilian,Sun, Lei,Liu, Qinggang,Yang, Xiaofeng,Ye, Xue,Hu, Yancheng,Huang, Yanqiang
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p. 2080 - 2085
(2017/07/24)
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- Heterocyclic compound and organic light-emitting device including the same
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A heterocyclic compound represented by Formula 1 below, and an organic light-emitting device including the heterocyclic compound:
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Page/Page column 88
(2017/08/26)
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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 0048; 0049; 0050; 0051
(2018/04/01)
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- Heterocyclic compounds, comprising of organic light-emitting device and organic light emitting display
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Heterocyclic compounds, synthetic methods for preparing the same, and organic light-emitting display devices comprising the same are described. The subject heterocyclic compounds may comprise an aromatic ring or a heteroaromatic ring fused with a carbazole, dibenzothiophene, or dibenzofurane derivative, the compounds featuring rigid backbone structures with high glass transition temperatures and high melting points. The subject heterocyclic compounds may exhibit high electrical stability, improved charge transport ability, high heat resistance and improved light-emitting properties when used in organic light-emitting devices. Organic light-emitting display devices prepared according to the present invention exhibit lower driving voltages, increased luminescent efficiencies and longer lifetimes.
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Paragraph 0294; 0299; 0300
(2017/09/13)
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- Visible Light-Mediated Copper(I)-Catalysed Aerobic Oxidation of Ynamides/Ynamines at Room Temperature: A Sustainable Approach to the Synthesis of α-Ketoimides/α-Ketoamides
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A novel visible light-mediated, copper-catalysed aerobic oxidation of the C≡C bond in ynamides/ynamines at room temperature by using molecular oxygen as an oxidant is described. Overall, 23 examples were demonstrated with substrates having a wide range of functional groups. The current protocol can be readily scaled up to a preparative (1–2 g) scale with high yields (78–92%), high atom efficiency, and reaction mass efficiency. The mechanistic study shows that in-situ formation of a copper(I)-coordinated π-complex (λmax=460 nm) is most probably the key light absorbing species responsible for the visible light-induced oxidation of ynamides and ynamines. This sustainable oxidation approach allows the direct synthesis of potentially important novel α-ketoimide/α-ketoamide skeletons without the need of external oxidants (organic/inorganic oxidants) and generation of stoichiometric amounts of wastes. (Figure presented.).
- Ragupathi, Ayyakkannu,Charpe, Vaibhav Pramod,Sagadevan, Arunachalam,Hwang, Kuo Chu
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supporting information
p. 1138 - 1143
(2017/04/11)
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- Transition-metal-free one-pot synthesis of alkynyl selenides from terminal alkynes under aerobic and sustainable conditions
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Alkynyl selenides were synthesized by a straightforward one-pot and three-step methodology, without the need of diselenides as starting reagents, under an oxygen atmosphere and using PEG 200 as the solvent. This procedure involves the in situ generation of dialkyl diselenides through a K3PO4-assisted reaction of an alkyl selenocyanate obtained by a nucleophilic substitution reaction between KSeCN and alkyl halides. Successive reaction with terminal alkynes in the presence of t-BuOK affords the corresponding alkyl alkynyl selenide in moderate to good yields. Finally, this methodology allowed the synthesis of 2-alkylselanyl-substituted benzofuran and indole derivatives starting from convenient 2-substituted acetylenes.
- Heredia, Adrián A.,Pe?é?ory, Alicia B.
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p. 910 - 918
(2017/06/21)
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- Sequential Addition of Phosphine to Alkynes for the Selective Synthesis of 1,2-Diphosphinoethanes under Catalysis. Well-Defined NHC-Copper Phosphides vs in Situ CuCl2/NHC Catalyst
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The well-defined NHC-copper phosphides [(NHC)CuPPh2]3 (1, NHC = 1,3-diisopropyl-4,5-dimethylimidazol-2-ylidene (IiPr); 2, NHC = N,N-di-tert-butylimidazol-2-ylidene (ItBu)) have been prepared by the reaction of simple copper halides with HPPh2 in the presence of N-heterocyclic carbenes (NHCs). Complexes 1 and 2 enabled catalytic double hydrophosphination of alkyl and aryl terminal alkynes to yield 1,2-diphosphinoethanes selectively in good yields. On the basis of these results, the most efficient and pratical in situ CuCl2/NHC catalyst has been developed. It catalyzes the selective double hydrophosphination of the alkynes with high efficiency and a wide substrate scope and exhibits even better performance than the well-defined NHC-Cu phosphides. The mechanistic studies disclosed that the formation of a copper acetylide in the catalytic cycle played an important role in the acceleration of the catalytic process.
- Yuan, Jia,Zhu, Lizhao,Zhang, Jianying,Li, Jianfeng,Cui, Chunming
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supporting information
p. 455 - 459
(2017/04/26)
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- Dehalogenation of vicinal dihalo compounds by 1,1′-bis(trimethylsilyl)-1: H,1′ H-4,4′-bipyridinylidene for giving alkenes and alkynes in a salt-free manner
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We report a transition metal-free dehalogenation of vicinal dihalo compounds by 1,1′-bis(trimethylsilyl)-1H,1′H-4,4′-bipyridinylidene (1) under mild conditions, in which trimethylsilyl halide and 4,4′-bipyridine were generated as byproducts. The synthetic protocol for this dehalogenation reaction was effective for a wide scope of dibromo compounds as substrates while keeping the various functional groups intact. Furthermore, the reduction of vicinal dichloro alkanes and vicinal dibromo alkenes also proceeded in a salt-free manner to afford the corresponding alkenes and alkynes.
- Rej, Supriya,Pramanik, Suman,Tsurugi, Hayato,Mashima, Kazushi
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supporting information
p. 13157 - 13160
(2017/12/26)
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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
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supporting information
p. 9979 - 9982
(2017/12/26)
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- New cyclometalated iridium(III) dye chromophore complexes for n-type dye-sensitised solar cells
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The synthesis of seven iridium complexes where aryl-1,2,3-triazole (Ar-tz) moieties act as cyclometalating ligands with 2,2′-bipyridyl-4,4′-dicarboxylic acid (dcb) as a N^N ancillary/anchoring ligand, is described. The new dye complexes [Ir(Ar-tz)2(dcb)][PF6] (AS1-7) were prepared in a two stage procedure with iridium-chloride dimer isolation. DFT analysis together with photophysical investigations reveal how using different substituents on the phenyl ring, or a different aryl system, lead to the tuning of the absorption and emission properties of these complexes. Computational studies therefore demonstrate an ideal HOMO-LUMO directionality for the [Ir(Ar-tz)2(dcb)]+framework, promoting a favourable electron transfer into the TiO2conduction band upon photoexcitation. Preliminary unoptimized tests on TiO2DSSCs have been carried out which show similar photovoltaic performance to the [Ir(ppy)2(dcb)][PF6] (ppy = 2-phenylpyridine) benchmark.
- Sinopoli, Alessandro,Wood, Christopher J.,Gibson, Elizabeth A.,Elliott, Paul I.P.
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supporting information
p. 81 - 89
(2016/12/26)
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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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- A oligomeric phenylacetylene compound and its preparation method and application
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The invention provides oligomeric phenylene ethynylene (OPE) compounds in formulas (I) and (II) shown in the specification as well as a preparation method and application thereof as photosensitizers in the photo-induced antibacterial process. An OPE molecule with length of about 2.8nm is synthesized by adopting the preparation method and the water solubility of the OPE compounds is increased by a method of introducing amino to the terminal. The OPE compounds have the advantages of simple synthetic routes, mild conditions, universal reagents and high yield, are suitable for amplification production and have good photo-induced antibacterial effects. The antibacterial experiments show that the OPE compounds in the formulas (I) and (II) have good photoactive antibacterial effects, can give play to the antibacterial activities when ultraviolet light and white light are used as light sources for illumination and have weak antibacterial effects without illumination.
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Paragraph 0020; 0021
(2017/08/25)
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- Products of the Propargyl Self-Reaction at High Temperatures Investigated by IR/UV Ion Dip Spectroscopy
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The propargyl radical is considered to be of key importance in the formation of the first aromatic ring in combustion processes. Here we study the bimolecular (self-) reactions of propargyl in a high-temperature pyrolysis flow reactor. The aromatic reaction products are identified by IR/UV ion dip spectroscopy, using the free electron laser FELIX as mid-infrared source. This technique combines mass selectivity with structural sensitivity. We identified several aromatic reaction products based on their infrared spectra, among them benzene, naphthalene, phenanthrene, indene, biphenyl, and surprisingly a number of aromatic compounds with acetylenic (ethynyl) side chains. The observation of benzene confirms that propargyl is involved in the formation of the first aromatic ring. The observation of compounds with acetylenic side chains shows that, in addition to a propargyl- and phenyl-based mechanism, the HACA (hydrogen abstraction C2H2 addition) mechanism of polycyclic aromatic hydrocarbons formation is present, although no acetylene was used as a reactant. On the basis of the experimental results we suggest a mechanism that connects the two pathways.
- Constantinidis,Hirsch,Fischer,Dey,Rijs
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p. 181 - 191
(2017/06/07)
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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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- 2,4,6-Triaminopyrimidine as a Novel Hinge Binder in a Series of PI3Kδ Selective Inhibitors
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Inhibition of phosphoinositide 3-kinase δ (PI3Kδ) is an appealing target for several hematological malignancies and inflammatory diseases. Herein, we describe the discovery and optimization of a series of propeller shaped PI3Kδ inhibitors comprising a novel triaminopyrimidine hinge binder. Combinations of electronic and structural strategies were employed to mitigate aldehyde oxidase mediated metabolism. This medicinal chemistry effort culminated in the identification of 52, a potent and highly selective inhibitor of PI3Kδ that demonstrates efficacy in a rat model of arthritis.
- Patel, Leena,Chandrasekhar, Jayaraman,Evarts, Jerry,Haran, Aaron C.,Ip, Carmen,Kaplan, Joshua A.,Kim, Musong,Koditek, David,Lad, Latesh,Lepist, Eve-Irene,McGrath, Mary E.,Novikov, Nikolai,Perreault, Stephane,Puri, Kamal D.,Somoza, John R.,Steiner, Bart H.,Stevens, Kirk L.,Therrien, Joseph,Treiberg, Jennifer,Villase?or, Armando G.,Yeung, Arthur,Phillips, Gary
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p. 3532 - 3548
(2016/05/19)
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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
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supporting information
p. 3056 - 3059
(2016/07/12)
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- 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
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supporting information
p. 11485 - 11489
(2016/10/24)
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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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- Difluorocyclobutylacetylenes as positive allosteric modulators of mGluR5 with reduced bioactivation potential
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Schizophrenia is a serious illness that affects millions of patients and has been associated with N-methyl-D-aspartate receptor (NMDAR) hypofunction. It has been demonstrated that activation of metabotropic glutamate receptor 5 (mGluR5) enhances NMDA receptor function, suggesting the potential utility of mGluR5 positive allosteric modulators (PAMs) in the treatment of schizophrenia. Herein we describe the optimization of an mGluR5 PAM by replacement of a phenyl with aliphatic heterocycles and carbocycles as a strategy to reduce bioactivation in a biaryl acetylene chemotype. Replacement with a difluorocyclobutane followed by further optimization culminated in the identification of compound 32, a low fold shift PAM with reduced bioactivation potential. Compound 32 demonstrated favorable brain uptake and robust efficacy in mouse novel object recognition (NOR) at low doses.
- Degnan, Andrew P.,Maxwell, Darrell,Balakrishnan, Anand,Brown, Jeffrey M.,Easton, Amy,Gulianello, Michael,Hanumegowda, Umesh,Hill-Drzewi, Melissa,Miller, Regina,Santone, Kenneth S.,Senapati, Arun,Shields, Eric E.,Sivarao, Digavalli V.,Westphal, Ryan,Whiterock, Valerie J.,Zhuo, Xiaoliang,Bronson, Joanne J.,Macor, John E.
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supporting information
p. 5871 - 5876
(2016/12/06)
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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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- Aryl Nitriles from Alkynes Using tert -Butyl Nitrite: Metal-Free Approach to C≡C Bond Cleavage
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Alkyne C≡C bond breaking, outside of alkyne metathesis, remains an underdeveloped area in reaction discovery. Recently, nitrogenation has been reported to allow nitrile formation from alkynes. A new protocol for the metal-free C≡C bond cleavage of terminal alkynes to produce nitriles is reported. This method provides an opportunity to synthesize a vast range of nitriles containing aryl, heteroaryl, and natural product derivatives (38 examples). In addition, the potential of tBuONO to act as a powerful nitrogenating agent for terminal aryl alkynes is demonstrated. (Figure Presented).
- Dutta, Uttam,Lupton, David W.,Maiti, Debabrata
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supporting information
p. 860 - 863
(2016/03/01)
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