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Search for "ketones" in Full Text gives 610 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.

Photocatalytic trifluoromethoxylation of arenes and heteroarenes in continuous-flow

  • Alexander V. Nyuchev,
  • Ting Wan,
  • Borja Cendón,
  • Carlo Sambiagio,
  • Job J. C. Struijs,
  • Michelle Ho,
  • Moisés Gulías,
  • Ying Wang and
  • Timothy Noël

Beilstein J. Org. Chem. 2020, 16, 1305–1312, doi:10.3762/bjoc.16.111

Graphical Abstract
  • results were obtained with carbonyl-containing compounds. Different aromatic ketones, aldehydes, esters, and carboxylic acids were transformed to the corresponding trifluoromethoxylated compounds (12–23) with generally good to high yields, except for 13, 16, 19 and 22 which were obtained in moderate or
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Published 15 Jun 2020

Ferrocenyl-substituted tetrahydrothiophenes via formal [3 + 2]-cycloaddition reactions of ferrocenyl thioketones with donor–acceptor cyclopropanes

  • Grzegorz Mlostoń,
  • Mateusz Kowalczyk,
  • André U. Augustin,
  • Peter G. Jones and
  • Daniel B. Werz

Beilstein J. Org. Chem. 2020, 16, 1288–1295, doi:10.3762/bjoc.16.109

Graphical Abstract
  • capillaries with a Melt Temp II apparatus. Starting materials: D–A cyclopropanes 5a–g were obtained following the reported procedure [28]. Ferrocenyl thioketones 8a–g were obtained by thionation of corresponding ferrocenyl ketones [29] by treatment with Lawesson’s reagent [30]. Ferrocenyl β-naphthyl
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Published 10 Jun 2020

Oxime radicals: generation, properties and application in organic synthesis

  • Igor B. Krylov,
  • Stanislav A. Paveliev,
  • Alexander S. Budnikov and
  • Alexander O. Terent’ev

Beilstein J. Org. Chem. 2020, 16, 1234–1276, doi:10.3762/bjoc.16.107

Graphical Abstract
  • iminoxyl radicals: generation, structure, stability, and spectral data Iminoxyl radicals were first discovered in 1964 by EPR spectroscopy as short-living intermediates formed from the oximes of both aromatic and aliphatic ketones and aldehydes, as well as from the oximes of quinones under the action of a
  • the corresponding C–O coupling products 51 (Scheme 20). The yields were close to that obtained with in situ generated of iminoxyl radicals (Scheme 19). Recently, the oxidative C–O coupling of oximes with acetonitrile, esters 52, and ketones 53 was realized [95] (Scheme 21). The authors suggested a
  • oximes reacted with esters and ketones to give oxidative coupling products in moderate to good yields (products 55a–e and 56a–e, respectively). In the case of asymmetric ketones, the C–H bond at the more substituted carbon was cleaved (products 56d,e). Recently, the copper-catalyzed addition of oximes to
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Published 05 Jun 2020

Activated carbon as catalyst support: precursors, preparation, modification and characterization

  • Melanie Iwanow,
  • Tobias Gärtner,
  • Volker Sieber and
  • Burkhard König

Beilstein J. Org. Chem. 2020, 16, 1188–1202, doi:10.3762/bjoc.16.104

Graphical Abstract
  • of carboxyl groups, ketones or aldehydes, C=C double bonds, aromatic rings and ether C–O stretching bonds, respectively [65][82][115]. Changes of the surface properties due to the modification of the activated carbon samples can also be detected by FTIR measurements. Shafeeyan et al. investigated new
  • the surface of the treated carbons in form of carboxyl groups, ketones, ether groups and carboxyl-carbonate structures is higher using nitric acid compared to hydrogen peroxide [116]. Nitrogen adsorption–desorption isotherms: The surface area and pore size distribution of solid catalyst materials can
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Published 02 Jun 2020

Photocatalysis with organic dyes: facile access to reactive intermediates for synthesis

  • Stephanie G. E. Amos,
  • Marion Garreau,
  • Luca Buzzetti and
  • Jerome Waser

Beilstein J. Org. Chem. 2020, 16, 1163–1187, doi:10.3762/bjoc.16.103

Graphical Abstract
  • , such as acridiniums (OD1–4), cyanoarenes (OD5–8), diaryl ketones (OD9/10), flavins (OD11/12), xanthenes (OD13–15), thiazines (OD16/17) and various other dyes, such as OD18–21, have been exploited (Figure 1), and the field of organic photocatalysis has been extensively covered by various reviews [16][19
  • , Fagnoni and co-workers developed an organophotocatalytic method to access nonsymmetrical ketones through the oxidation of the alkyl acylsilanes 18.1 (Eox ≈ +1.3 V) by an acridinium photocatalyst OD2 (E(PC+*/PC) ≈ 2.1 V, Scheme 18) [90]. After the fragmentation, the acyl radical can add to various Michael
  • intermediate of important reactions, such as the pinacol [101] or the McMurry coupling [102]. Recently, photocatalysis has been used to access ketyl radicals through the reduction of ketones with a suitable transition metal-based photocatalyst [103] or organic dye [104]. The protonation of this type of
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Published 29 May 2020

Copper-based fluorinated reagents for the synthesis of CF2R-containing molecules (R ≠ F)

  • Louise Ruyet and
  • Tatiana Besset

Beilstein J. Org. Chem. 2020, 16, 1051–1065, doi:10.3762/bjoc.16.92

Graphical Abstract
  • the SCF2PO(OEt)2 derivatives [53]. In the same vein, the reaction of the CuCF2PO(OEt)2 species, generated from CuSCN, with α-bromoketones provided the α-SCF2PO(OEt)2-containing ketones [54] (Scheme 10). In 2019, the group of Goossen developed an approach to access SCF2PO(OEt)2-containing arenes based
  • -designed complex [70]. In 2015, Grushin reported the generation of four well-defined CuC2F5 complexes, namely (Ph3P)2CuCF2CF3, (bpy)CuCF2CF3, (IPr*)CuCF2CF3 and (Ph3P)Cu(Phen)CF2CF3. The reactivity of the latter was studied for the synthesis of pentafluoroethyl ketones from acyl chlorides [71]. Indeed, the
  • )CuCF2CF3 complex. 19F NMR yields were determined using 4-trifluoromethoxyanisole as the internal standard. aIsolated yields. Synthesis of pentafluoroethyl ketones using the (Ph3P)Cu(phen)CF2CF3 reagent. 19F NMR yields were given using 1,3-bis(trifluoromethyl)benzene as the internal standard. Synthesis of
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Published 18 May 2020

Recent applications of porphyrins as photocatalysts in organic synthesis: batch and continuous flow approaches

  • Rodrigo Costa e Silva,
  • Luely Oliveira da Silva,
  • Aloisio de Andrade Bartolomeu,
  • Timothy John Brocksom and
  • Kleber Thiago de Oliveira

Beilstein J. Org. Chem. 2020, 16, 917–955, doi:10.3762/bjoc.16.83

Graphical Abstract
  • the diazonium salts, as well as the enol acetates are reported giving versatile α-aryl ketones/aldehydes in both batch and continuous-flow conditions (20 examples in 26–88% yields) [9]. A comparison between batch and flow conditions was performed showing that similar yields are obtained (batch 82% vs
  • and HEH act respectively as electron and hydrogen donors. The protocol was efficient for dehalogenations with bromine- and iodine-containing acetophenone derivatives (75–98% yields). However, it was much less efficient with chloro ketones (12–40% yields) and not effective with α-bromo esters and α
  • hydration of terminal alkynes to ketones can be photocatalyzed by rhodium(III) tetrakis(p-sulfonylphenyl)porphyrin (RhIIITSPP) [37]. The coupling between RhIII(TSPP) and terminal alkynes produced the β-carbonylalkylrhodium porphyrin as a photoactive intermediate, whose irradiation produced the PhCOCH2
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Published 06 May 2020

Copper catalysis with redox-active ligands

  • Agnideep Das,
  • Yufeng Ren,
  • Cheriehan Hessin and
  • Marine Desage-El Murr

Beilstein J. Org. Chem. 2020, 16, 858–870, doi:10.3762/bjoc.16.77

Graphical Abstract
  • phenols, ketones and 1,3-dienes (Scheme 6) [27]. C–C bond formation Complexes of radical and redox-active ligands with transition metals are known to be able to promote radical reactions through single-electron transfer (SET) processes [28]. Expanding on the research area pioneered by Wieghardt and
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Published 24 Apr 2020

Aldehydes as powerful initiators for photochemical transformations

  • Maria A. Theodoropoulou,
  • Nikolaos F. Nikitas and
  • Christoforos G. Kokotos

Beilstein J. Org. Chem. 2020, 16, 833–857, doi:10.3762/bjoc.16.76

Graphical Abstract
  • capable to induce other types of reactions, such as hydrogen atom abstraction (HAT) processes or triplet state energy transfer processes (EnT). Carbonyl compounds, especially diaryl ketones, have shown great potential as far as their catalytic scope is concerned. Benzophenone or acetophenone (64) and
  • similar derivatives have already been used in a plethora of chemical transformations, and their photochemical properties have been studied extensively [11]. In an attempt to mimic the potential of ketones, various aldehydes have been employed as photocatalysts or photoinitiators. Even if aromatic ketones
  • aliphatic ketones and aldehydes to olefins upon excitation of the carbonyl compound [12]. More specifically, aliphatic ketones and aldehydes can absorb irradiation in the long-wavelength region (240–340 nm), which is then transformed into electronic excitation through the S1 (n,π*) transition, excitation of
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Published 23 Apr 2020

Reaction of indoles with aromatic fluoromethyl ketones: an efficient synthesis of trifluoromethyl(indolyl)phenylmethanols using K2CO3/n-Bu4PBr in water

  • Thanigaimalai Pillaiyar,
  • Masoud Sedaghati and
  • Gregor Schnakenburg

Beilstein J. Org. Chem. 2020, 16, 778–790, doi:10.3762/bjoc.16.71

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  • , D-53121 Bonn, Germany 10.3762/bjoc.16.71 Abstract A new, mild and efficient protocol for the synthesis of trifluoromethyl(indolyl)phenylmethanols by the reaction of indoles with a variety of aromatic fluoromethyl ketones in the presence of K2CO3 (15 mol %) and n-Bu4PBr (15 mol %) in water. The
  • be synthesized by Friedel–Crafts hydroxyalkylation reactions of indoles with trifluoromethyl ketones in the presence of either Lewis/Bronsted acid catalysts. Bandini et al. reported the trifluoromethyl hydroxyalkylation of indoles catalyzed by an organic base 2-tert-butyl-1,1,3,3-tetramethylguanidine
  • ketones were investigated, and the results are summarized in Table 2. Trifluoroacetophenones having a halogen substituent at the para-position of the phenyl ring such as p-F (2b), p-Cl (2c), and p-Br (2d) provided the corresponding trifluoro-1-(1H-indol-3-yl)ethan-1-ols 3b, 3c, and 3d in 97, 92 and 89
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Published 20 Apr 2020

Recent advances in Cu-catalyzed C(sp3)–Si and C(sp3)–B bond formation

  • Balaram S. Takale,
  • Ruchita R. Thakore,
  • Elham Etemadi-Davan and
  • Bruce H. Lipshutz

Beilstein J. Org. Chem. 2020, 16, 691–737, doi:10.3762/bjoc.16.67

Graphical Abstract
  • silyl ethers 89–92 (Scheme 18), thus showcasing the synergistic relationship between Pd and Cu catalysis [43]. Driven by the success of earlier results, the authors utilized 78 for reductive couplings between ketones 93 and imines 97 as electrophiles to form unsymmetrical 1,2-diols 94–96 and 1,2-amino
  • alcohols 98–100, respectively. Palladium was no longer needed for these transformations. The scope of the reaction with ketones was not limited to diaryl species and aryl ketones participated in the reaction, including those with more hindered alkyl groups (Scheme 19) [44]. This discovery was followed by a
  • -additions of cuprates derived from a silyllithium [47] to α,β-unsaturated ketones [48]. There was no effort made at that time to convert these reactions to the corresponding catalytic processes, rather, the accent was more towards using the silyl group introduced as a hydroxy group equivalent [49][50][51
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Published 15 Apr 2020

Asymmetric synthesis of CF2-functionalized aziridines by combined strong Brønsted acid catalysis

  • Xing-Fa Tan,
  • Fa-Guang Zhang and
  • Jun-An Ma

Beilstein J. Org. Chem. 2020, 16, 638–644, doi:10.3762/bjoc.16.60

Graphical Abstract
  • dr values, including alkyl or halogen-substituted phenyl and 2-naphthyl ketones (Scheme 2). Unfortunately, phenylglyoxal monohydrates bearing strong electron-withdrawing groups were not compatible with the current conditions. X-ray analysis of aziridine 4a confirmed the absolute configuration of the
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Published 07 Apr 2020

Efficient synthesis of 3,6,13,16-tetrasubstituted-tetrabenzo[a,d,j,m]coronenes by selective C–H/C–O arylations of anthraquinone derivatives

  • Seiya Terai,
  • Yuki Sato,
  • Takuya Kochi and
  • Fumitoshi Kakiuchi

Beilstein J. Org. Chem. 2020, 16, 544–550, doi:10.3762/bjoc.16.51

Graphical Abstract
  • ][21][22][23][24][25][26][27][28][29][30][31][32][33]. In the presence of ruthenium carbonyl phosphine complexes, the reaction of aromatic ketones possessing C–H bonds or C–OR (R = alkyl) bonds with arylboronates provided C–H or C–O arylation products [21][22][23][24][25][26][27][28][29][30][31][32][33
  • introduction of two different aryl groups at the ortho-positions can be achieved by chemoselective C–O arylation of aromatic ketones possessing both C–H and C–O bonds and subsequent C–H arylation. We envisioned that the application of this strategy to the anthraquinone template would provide its derivatives
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Published 31 Mar 2020

Regio- and stereoselective synthesis of new ensembles of diversely functionalized 1,3-thiaselenol-2-ylmethyl selenides by a double rearrangement reaction

  • Svetlana V. Amosova,
  • Andrey A. Filippov,
  • Nataliya A. Makhaeva,
  • Alexander I. Albanov and
  • Vladimir A. Potapov

Beilstein J. Org. Chem. 2020, 16, 515–523, doi:10.3762/bjoc.16.47

Graphical Abstract
  • was developed during the last ten years based on new directions for nucleophilic substitution reactions proceeding via intermediate seleniranium cations 2 generated from thiaselenole 1. We have carried out new regioselective reactions of thiaselenole 1 with dithiocarbamates [31], ketones [37], thiols
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Published 27 Mar 2020

Recent advances in photocatalyzed reactions using well-defined copper(I) complexes

  • Mingbing Zhong,
  • Xavier Pannecoucke,
  • Philippe Jubault and
  • Thomas Poisson

Beilstein J. Org. Chem. 2020, 16, 451–481, doi:10.3762/bjoc.16.42

Graphical Abstract
  • ketones and furanyl ketones, for instance, with good yield. To explain the reaction outcome, the authors suggested that the [Cu(I)(dap)2]Cl catalyst acted as an electron shuttle between the halide derivative and the allylmetal reagent, precluding a direct electron transfer between the allylstannane and
  • chlorides [20]. This ATRA reaction was carried out with various fluoroalkylsulfonyl chlorides, such as CFH2SO2Cl, CF2HSO2Cl, CF3SO2Cl, CF3CH2SO2Cl, and C4F9SO2Cl, electron-deficient alkenes, including α,β-unsaturated ketones, amides, esters, carboxylic acids, sulfones, and phosphonates (Scheme 4). In
  • addition of a trifluoromethyl radical to silyl enol ethers derived from ketones using the same reaction conditions (Scheme 12) [28]. 1.3 Oxidation reactions In 2015, Bissember and co-workers used the Sauvage catalyst to generate an α-amino radical, which was used to perform the synthesis of annulated
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Published 23 Mar 2020

Copper-promoted/copper-catalyzed trifluoromethylselenolation reactions

  • Clément Ghiazza and
  • Anis Tlili

Beilstein J. Org. Chem. 2020, 16, 305–316, doi:10.3762/bjoc.16.30

Graphical Abstract
  • trifluoromethylselenolated alkyne product could be isolated. After that, the same group studied the α-trifluoromethylselenolation of ketones and esters starting from the corresponding halides or diazoacetates (Scheme 4) [19][20]. Both methods led to the desired products with moderate to very good yields, and the reactions
  • carbonyl compounds with [(bpy)CuSeCF3]2 by the group of Weng. Trifluoromethylselenolation of α,β-unsaturated ketones with [(bpy)CuSeCF3]2 by the group of Weng. Trifluoromethylselenolation of acid chlorides with [(bpy)CuSeCF3]2 by the group of Weng. Synthesis of 2-trifluoromethylselenylated benzofused
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Published 03 Mar 2020

Ultrasonic-assisted unusual four-component synthesis of 7-azolylamino-4,5,6,7-tetrahydroazolo[1,5-a]pyrimidines

  • Yana I. Sakhno,
  • Maryna V. Murlykina,
  • Oleksandr I. Zbruyev,
  • Anton V. Kozyryev,
  • Svetlana V. Shishkina,
  • Dmytro Sysoiev,
  • Vladimir I. Musatov,
  • Sergey M. Desenko and
  • Valentyn A. Chebanov

Beilstein J. Org. Chem. 2020, 16, 281–289, doi:10.3762/bjoc.16.27

Graphical Abstract
  • α,β-unsaturated ketones [8][9][10][11] or via their multicomponent analogues. On the other hand, multicomponent reactions (MCRs) directly leading to tetrahydroazolopyrimidine heterocyclic systems have also been published [4][5][16][17][18][19][20][21][22][23][24]. In particular, multicomponent
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Published 27 Feb 2020

Copper-catalyzed enantioselective conjugate addition of organometallic reagents to challenging Michael acceptors

  • Delphine Pichon,
  • Jennifer Morvan,
  • Christophe Crévisy and
  • Marc Mauduit

Beilstein J. Org. Chem. 2020, 16, 212–232, doi:10.3762/bjoc.16.24

Graphical Abstract
  • , and Grignard reagents to Michael acceptors. In that respect, since the pioneering example reported by Alexakis and co-workers in 1993 [5], a wide range of cyclic and acyclic electron-deficient alkenes, such as α,β-unsaturated ketones, esters, nitriles, sulfones, or nitroolefines, was intensively
  • . However, as depicted in Scheme 1, due to their stronger reactivity than that of usual esters or ketones, a competitive 1,2-addition to the carbonyl function of enals could occur, leading to the corresponding alcohol as a byproduct. Moreover, even if the 1,4-addition is favored, thanks to the copper/ligand
  • , the acylimidazole moiety constituted a privileged surrogate of esters, amides, ketones, and aldehydes. Indeed, this peculiar function, which was readily accessible from the corresponding aldehydes or Weinreb amides, could be efficiently converted into a wide range of carbonyl derivatives, as depicted
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Published 17 Feb 2020

Combination of multicomponent KA2 and Pauson–Khand reactions: short synthesis of spirocyclic pyrrolocyclopentenones

  • Riccardo Innocenti,
  • Elena Lenci,
  • Gloria Menchi and
  • Andrea Trabocchi

Beilstein J. Org. Chem. 2020, 16, 200–211, doi:10.3762/bjoc.16.23

Graphical Abstract
  • reaction to achieve spirocyclic pyrrolocyclopentenone derivatives. Specifically, the KA2 reaction was envisaged taking into account cyclic ketones, to install a quaternary carbon atom carrying the required 1,6-enyne moiety for the subsequent Pauson–Khand reaction, thus achieving the corresponding tricylic
  • spirocyclopentenone derivative, although in slightly lower yield as compared for the homologous ketone (Table 1, entry 5). No conversion to the KA2 adduct was achieved by using unsaturated or aromatic ketones (Table 1, entries 7 and 8, respectively), confirming an important role of the electronic content of the
  • molecular platforms for the generation of high-quality small molecule collections, taking advantage of their three-dimensional shape and structural bias to develop lead compounds. The combination of multicomponent KA2 and Pauson–Khand reactions using representative cyclic ketones, allylamine and
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Published 12 Feb 2020

The reaction of arylmethyl isocyanides and arylmethylamines with xanthate esters: a facile and unexpected synthesis of carbamothioates

  • Narasimhamurthy Rajeev,
  • Toreshettahally R. Swaroop,
  • Ahmad I. Alrawashdeh,
  • Shofiur Rahman,
  • Abdullah Alodhayb,
  • Seegehalli M. Anil,
  • Kuppalli R. Kiran,
  • Chandra,
  • Paris E. Georghiou,
  • Kanchugarakoppal S. Rangappa and
  • Maralinganadoddi P. Sadashiva

Beilstein J. Org. Chem. 2020, 16, 159–167, doi:10.3762/bjoc.16.18

Graphical Abstract
  • ], iron nanoparticle-catalyzed reactions of 2-naphthol with benzaldehyde and some of its derivatives with thiourea [22], isothiocyanato oxindoles with ketones [23], ammonium isothiocyanates with chalcones [24], and α-isothiocyanato esters with α-keto amides [25]. Among the synthetic methods available for
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Published 03 Feb 2020

[1,3]/[1,4]-Sulfur atom migration in β-hydroxyalkylphosphine sulfides

  • Katarzyna Włodarczyk,
  • Piotr Borowski and
  • Marek Stankevič

Beilstein J. Org. Chem. 2020, 16, 88–105, doi:10.3762/bjoc.16.11

Graphical Abstract
  • set of substrates 6–25 was prepared from dimethylphenylphosphine sulfide 4 (Table 1). All compounds were obtained in good yields, both from aldehydes and ketones. For aldehydes and unsymmetrically substituted ketones, the formation of the products as diastereomeric mixtures could be observed
  • -hydroxyalkylphosphine sulfides (Table 2). As it turned out, the sulfides derived from aldehydes 7–9 and 11 failed to undergo a rearrangement (Table 2, entries 1–4). On the other hand, compounds derived from ketones 12, 14–17, and 20–25 underwent a ‘clean’ reaction under the conditions. However, instead of cyclization
  • 1–5). On the other hand, most of the substrates derived from ketones 12–16 and 18–25 underwent intramolecular sulfur migration with the formation of mainly β-mercaptoalkylphosphine oxides in very good yields (Table 3, entries 6, 8–10, and 12–18). Only in the case of compounds 16 and 21, the
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Published 21 Jan 2020

Construction of trisubstituted chromone skeletons carrying electron-withdrawing groups via PhIO-mediated dehydrogenation and its application to the synthesis of frutinone A

  • Qiao Li,
  • Chen Zhuang,
  • Donghua Wang,
  • Wei Zhang,
  • Rongxuan Jia,
  • Fengxia Sun,
  • Yilin Zhang and
  • Yunfei Du

Beilstein J. Org. Chem. 2019, 15, 2958–2965, doi:10.3762/bjoc.15.291

Graphical Abstract
  • ][76][77], converting alkynes and alkenes to ketones [78], oxidizing alcohols to aldehydes [79][80], as well as in the direct α-hydroxylation of ketones [81]. Furthermore, it could also be used to realize oxidative C–C [82], C–N [83], and C–O [84] bond formations. However, to the best of our knowledge
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Published 12 Dec 2019

Iodine-mediated hydration of alkynes on keto-functionalized scaffolds: mechanistic insight and the regiospecific hydration of internal alkynes

  • Zachary Lee,
  • Brandon R. Jones,
  • Nyochembeng Nkengbeza,
  • Michael Phillips,
  • Kayla Valentine,
  • Alexis Stewart,
  • Brandon Sellers,
  • Nicholas Shuber and
  • Karelle S. Aiken

Beilstein J. Org. Chem. 2019, 15, 2747–2752, doi:10.3762/bjoc.15.265

Graphical Abstract
  • of two equivalents of ICl, signals at 2.85–2.93 ppm, 3.96 ppm, and 4.36 ppm, in addition to the phenyl protons, were observed, without any evidence of 10 being present. Based on literature reports for α-iodo ketones [21][22], it was clear that the signal at 3.96 ppm corresponded to H-1 in 9. This was
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Published 14 Nov 2019

A review of asymmetric synthetic organic electrochemistry and electrocatalysis: concepts, applications, recent developments and future directions

  • Munmun Ghosh,
  • Valmik S. Shinde and
  • Magnus Rueping

Beilstein J. Org. Chem. 2019, 15, 2710–2746, doi:10.3762/bjoc.15.264

Graphical Abstract
  • asymmetric hydrogenation of ketones [22]. They showed that upon reduction with Raney nickel powder electrodes modified with (R,R)-(+)-tartaric acid, 2-hexanone 3 was converted to (S)-(+)-2-hexanol 4 with an average optical purity of 4%, whereas Raney nickel powder electrodes modified with (S,S)-(−)-tartaric
  • catalyze the enantioselective hydrogenation of prochiral ketones 18. The prochiral ketones such as acetophenone, 1-tetralone and 1-indanone were reduced to their corresponding alcohols 20a, 20b and 20c, respectively, with moderate optical yields, with formation of (S) as major enantiomer (Scheme 5). After
  • installation of an oxygen atom on one face, promoting the addition of CO2 from the other face, resulting in enantioenriched carboxylated product 29 after acidification (Scheme 10). The authors described similar results involving the asymmetric electrocarboxylation of other prochiral aromatic ketones in a
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Published 13 Nov 2019

Synthesis of aryl-substituted thieno[3,2-b]thiophene derivatives and their use for N,S-heterotetracene construction

  • Nadezhda S. Demina,
  • Nikita A. Kazin,
  • Nikolay A. Rasputin,
  • Roman A. Irgashev and
  • Gennady L. Rusinov

Beilstein J. Org. Chem. 2019, 15, 2678–2683, doi:10.3762/bjoc.15.261

Graphical Abstract
  • ketones were used to synthesize new N,S-heterotetracenes, namely 9H-thieno[2',3':4,5]thieno[3,2-b]indoles by their treatment with arylhydrazines in accordance with the Fischer indolization reaction. Keywords: Fiesselmann thiophene synthesis; Fischer indole synthesis; N,S-heteroacene; thieno[3,2-b
  • ]thiophen-3(2H)-ones 4a–k after neutralization of the reaction mixture with a mineral acid. It should be noted that the obtained ketones 4 were more sensitive to the presence of acids than their benzo-annelated counterparts [17][18]: when an excess of a mineral acid was used, we observed a decrease in
  • arylhydrazines 5b–d containing electron–acceptor substituents or electron–donor ones. There was no obvious change in the yields of compounds 6l–o (78–84%, Scheme 3), which may indicate that the starting ketones had a rather high reactivity. To confirm the structure of TTI derivatives 6, we attempted to grow
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Published 12 Nov 2019
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