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Search for "NHC" in Full Text gives 196 result(s) in Beilstein Journal of Organic Chemistry.

Visible-light-induced nickel-catalyzed α-hydroxytrifluoroethylation of alkyl carboxylic acids: Access to trifluoromethyl alkyl acyloins

  • Feng Chen,
  • Xiu-Hua Xu,
  • Zeng-Hao Chen,
  • Yue Chen and
  • Feng-Ling Qing

Beilstein J. Org. Chem. 2023, 19, 1372–1378, doi:10.3762/bjoc.19.98

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  • acyloins (Scheme 1a). Anand’s group [25] demonstrated that a NHC-catalyzed selective acyloin condensation between aromatic aldehydes and trifluoroacetaldehyde ethyl hemiacetal afforded the analogous products (Scheme 1b). In comparison, the synthesis of trifluoromethyl aliphatic acyloins is still
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Published 11 Sep 2023

Photoredox catalysis harvesting multiple photon or electrochemical energies

  • Mattia Lepori,
  • Simon Schmid and
  • Joshua P. Barham

Beilstein J. Org. Chem. 2023, 19, 1055–1145, doi:10.3762/bjoc.19.81

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  • and Epred = −2.10 V vs SCE for CF3Br) [93]. As a further application of conPET to atom transfer processes, the Wärnmark group recently disclosed an alternative protocol for the ATRA reaction of perfluoroalkyl iodides using the iron-based NHC complex [FeIII(btz)3](PF6)3 (btz = (3,3’-dimethyl-1,1’-bis(p
  • of iron CT states (in the nanosecond domain) enabled by the relatively longer lifetimes of e.g. Fe–NHC complexes [97][98][99][100]. In particular, the Wärnmark group reported two sets of conditions with and without Et3N as a sacrificial electron donor, to achieve reductive and oxidative quenching
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Published 28 Jul 2023

Asymmetric tandem conjugate addition and reaction with carbocations on acylimidazole Michael acceptors

  • Brigita Mudráková,
  • Renata Marcia de Figueiredo,
  • Jean-Marc Campagne and
  • Radovan Šebesta

Beilstein J. Org. Chem. 2023, 19, 881–888, doi:10.3762/bjoc.19.65

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  • 10.3762/bjoc.19.65 Abstract We present here a stereoselective tandem reaction based on the asymmetric conjugate addition of dialkylzinc reagents to unsaturated acylimidazoles followed by trapping of the intermediate zinc enolate with carbocations. The use of a chiral NHC ligand provides chiral zinc
  • control of RNA [16]. Moreover, Campagne and co-workers showed that Cu–NHC-catalyzed conjugate additions of dialkylzinc reagents proceed with high enantioselectivities [17][18][19]. Furthermore, this methodology allows iterative access to 1,3-disubstituted motifs that are present in various natural
  • a tandem reaction comprising the Cu–NHC-catalyzed addition of dialkylzinc reagents to enoyl imidazoles followed by a trapping reaction with various onium compounds (Scheme 1). In this work we show the development of this methodology and its application to a range of acylimidazoles and carbocations
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Published 16 Jun 2023

Pyridine C(sp2)–H bond functionalization under transition-metal and rare earth metal catalysis

  • Haritha Sindhe,
  • Malladi Mounika Reddy,
  • Karthikeyan Rajkumar,
  • Akshay Kamble,
  • Amardeep Singh,
  • Anand Kumar and
  • Satyasheel Sharma

Beilstein J. Org. Chem. 2023, 19, 820–863, doi:10.3762/bjoc.19.62

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  • styrenes 64 using a Ni–Al bimetallic system and NHC ligand 65 through intermolecular hydroarylation with high levels of enantio- and regioselectivity in the alkylated products 66 (Scheme 13). Also, the authors performed DFT studies revealing the reaction mechanism and supported that the interaction of the
  • NHC aryl part with trans-styrene was highly important for the reaction to proceed and for the enantiocontrolled formation of the products. Alkenylation The C–H alkenylation is another important C–C bond-forming reaction. Olefinated organic molecules like vinylarenes play a significant role as key
  • . Also, metal–NHC complexes have wide application in catalysis and various organic transformations and a range of metal–NHCs served as catalysts. In 2010, using NHC ligands, Yap and co-workers [90] developed a method for the direct para and meta-C–H alkenylation of pyridines with 4-octyne (107) using a
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Published 12 Jun 2023

Enolates ambushed – asymmetric tandem conjugate addition and subsequent enolate trapping with conventional and less traditional electrophiles

  • Péter Kisszékelyi and
  • Radovan Šebesta

Beilstein J. Org. Chem. 2023, 19, 593–634, doi:10.3762/bjoc.19.44

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  • -mediated epimerization. Guénée et al. described the allylation, benzylation, and propargylation of magnesium enolates. These enolates were generated by a Cu-NHC-catalyzed conjugate addition of Grignard reagents to β-substituted cyclic enones (70) (Scheme 19) [51]. Fox and co-workers developed an intriguing
  • or even complementary to boronates (e.g., sensitivity to organometallic reagents). In 2010, the Hoveyda group accomplished the NHC–Cu-catalyzed enantioselective conjugate addition of PhMe2Si-Bpin to α,β-unsaturated enones [88]. Additionally, they have also presented the successful trapping of the Cu
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Published 04 May 2023

Transition-metal-catalyzed domino reactions of strained bicyclic alkenes

  • Austin Pounder,
  • Eric Neufeld,
  • Peter Myler and
  • William Tam

Beilstein J. Org. Chem. 2023, 19, 487–540, doi:10.3762/bjoc.19.38

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  • product 29 as well as regenerates the Ni(0) catalyst. In 2022, the Tobisu group explored a two-component carboacylation of norbornene derivatives. Exploiting a Ni/NHC system, the authors were able to develop an entirely atom-economic carboacylation process utilizing N-indoyl arylamides [38]. In 2019
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Published 24 Apr 2023

Mechanochemical solid state synthesis of copper(I)/NHC complexes with K3PO4

  • Ina Remy-Speckmann,
  • Birte M. Zimmermann,
  • Mahadeb Gorai,
  • Martin Lerch and
  • Johannes F. Teichert

Beilstein J. Org. Chem. 2023, 19, 440–447, doi:10.3762/bjoc.19.34

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  • , Germany 10.3762/bjoc.19.34 Abstract A protocol for the mechanochemical synthesis of copper(I)/N-heterocyclic carbene complexes using cheap and readily available K3PO4 as base has been developed. This method employing a ball mill is amenable to typical simple copper(I)/NHC complexes but also to a
  • focus has seldomly been on the preparative methods to access the required catalysts themselves. As case in point, we decided to re-investigate the synthesis of copper(I)/N-heterocyclic carbene (NHC) complexes, which are broadly applicable catalysts for a wide variety of transformations [4][5][6]. While
  • generally there are many different synthetic routes to transition metal/NHC complexes [7][8][9][10][11][12][13][14][15] not all of them are applicable to the preparation of copper(I)/NHC compounds (Scheme 1) [5][6][13][16][17][18][19]. Generally, the so-called direct routes via the appropriate imidazol(in
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Published 14 Apr 2023

Combining the best of both worlds: radical-based divergent total synthesis

  • Kyriaki Gennaiou,
  • Antonios Kelesidis,
  • Maria Kourgiantaki and
  • Alexandros L. Zografos

Beilstein J. Org. Chem. 2023, 19, 1–26, doi:10.3762/bjoc.19.1

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  • asymmetric conjugate reaction of commercially available 81 and 82 using Fletcher’s protocol (94% ee) [44]. A subsequent intramolecular arylation in the α-position of the ketone of 83, catalyzed by a Pd(II)–NHC [45], followed by methylation, provided cis-decalin 84 (Scheme 7). Appropriate redox modifications
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Published 02 Jan 2023

Redox-active molecules as organocatalysts for selective oxidative transformations – an unperceived organocatalysis field

  • Elena R. Lopat’eva,
  • Igor B. Krylov,
  • Dmitry A. Lapshin and
  • Alexander O. Terent’ev

Beilstein J. Org. Chem. 2022, 18, 1672–1695, doi:10.3762/bjoc.18.179

Graphical Abstract
  • addition to the electron-rich C=C bond [58] or proton loss followed by β-functionalization [59][60][61]. The iminium cation catalysis is used in the activation of electrophilic properties of enones for the nucleophilic epoxidation by hydroperoxides (Scheme 2B). N-Heterocyclic carbene (NHC) organocatalysis
  • coupling, or deprotonation followed by the functionalization of α- and β-positions of the starting aldehyde. NHC-catalyzed photochemical processes [64] and oxidative cyclizations with heterocycle formation [65] were reviewed previously. Acidic molecules or hydrogen-bond donors are used as organocatalysts
  • -organocatalysts. Organocatalysis classification used in the present perspective. Oxidative processes catalyzed by amines. N-Heterocyclic carbene (NHC) catalysis in oxidative functionalization of aldehydes. Examples of asymmetric oxidative processes catalyzed by chiral Brønsted acids. Asymmetric aerobic α
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Published 09 Dec 2022

First example of organocatalysis by cathodic N-heterocyclic carbene generation and accumulation using a divided electrochemical flow cell

  • Daniele Rocco,
  • Ana A. Folgueiras-Amador,
  • Richard C. D. Brown and
  • Marta Feroci

Beilstein J. Org. Chem. 2022, 18, 979–990, doi:10.3762/bjoc.18.98

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  • per l’Ingegneria, Sapienza University, via del Castro Laurenziano, 7, 00161, Rome, Italy 10.3762/bjoc.18.98 Abstract In this paper we present the first electrochemical generation of NHC carried out in a divided flow cell. The flow cell operated in the recycle mode. The need for a divided cell derived
  • from the anodic electroactivity of the electrogenerated carbene. In order to have NHC accumulation in the catholyte, the Nafion membrane (cell separator) was pretreated with an alkaline solution. The formation of NHC was quantified as its reaction product with elemental sulfur. The NHC was successfully
  • can be modified by the presence of a base or by a single electron cathodic reduction of the C–H between nitrogen atoms of the imidazolium ring (Scheme 1), inducing the formation of a N-heterocyclic carbene (NHC) [7][8]. In recent years, NHCs have achieved great success: they have been frequently used
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Published 05 Aug 2022

Recent developments and trends in the iron- and cobalt-catalyzed Sonogashira reactions

  • Surendran Amrutha,
  • Sankaran Radhika and
  • Gopinathan Anilkumar

Beilstein J. Org. Chem. 2022, 18, 262–285, doi:10.3762/bjoc.18.31

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  • decrease in its activity. For comparison, the Sonogashira reaction of phenylacetylene and iodobenzene was performed in the presence of the two catalytic systems Co-NHC@MWCNTs and Co-NPS (Scheme 23 and Scheme 24). The reaction proceeded with four equivalents of KOH in EtOH/H2O at 65 °C. Aryl iodides showed
  • higher reactivity and less active aryl chlorides were successfully coupled to give the desired products in acceptable yields. The reaction carried out by both catalysts gave excellent yields of up to 98% for Co-NHC@MWCNTs and a still good yield of up to 91% for reactions catalyzed by Co-NPs. It was
  • various arylhalides and phenylacetylene in the presence of Co@imine-POP catalyst. Sonogashira coupling of aryl halides and phenylacetylene using Co-DMM@MNPs/chitosan. Sonogashira cross-coupling of aryl halides with terminal acetylenes in the presence of Co-NHC@MWCNTs. Sonogashira cross-coupling of aryl
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Published 03 Mar 2022

Chemoselective N-acylation of indoles using thioesters as acyl source

  • Tianri Du,
  • Xiangmu Wei,
  • Honghong Xu,
  • Xin Zhang,
  • Ruiru Fang,
  • Zheng Yuan,
  • Zhi Liang and
  • Yahui Li

Beilstein J. Org. Chem. 2022, 18, 89–94, doi:10.3762/bjoc.18.9

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  • NHC catalysis [15] (Scheme 1, A1). In 2019, Jiang and co-workers reported a dicarbonylation of amine and aryl borates using α-ketothioester as a stable 1,2-dicarbonyl reagent [16] (Scheme 1, B). Recently, we applied S-methyl butanethioate in a Pd-catalyzed transthioetherification or
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Published 10 Jan 2022

Biological properties and conformational studies of amphiphilic Pd(II) and Ni(II) complexes bearing functionalized aroylaminocarbo-N-thioylpyrrolinate units

  • Samet Poyraz,
  • Samet Belveren,
  • Sabriye Aydınoğlu,
  • Mahmut Ulger,
  • Abel de Cózar,
  • Maria de Gracia Retamosa,
  • Jose M. Sansano and
  • H. Ali Döndaş

Beilstein J. Org. Chem. 2021, 17, 2812–2821, doi:10.3762/bjoc.17.192

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  • ligands that could coordinate several metal centers with the aid of sulfur, nitrogen or oxygen donor atoms that allow multiple bindings [13]. Moreover, compounds bearing a –C(O)NHC(S)– moiety and their metal complexes have assorted biological and pharmacological properties such as anti(myco)bacterial
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Published 02 Dec 2021

Recent advances in organocatalytic asymmetric aza-Michael reactions of amines and amides

  • Pratibha Sharma,
  • Raakhi Gupta and
  • Raj K. Bansal

Beilstein J. Org. Chem. 2021, 17, 2585–2610, doi:10.3762/bjoc.17.173

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  • carbenes (NHC) In recent years, NHCs have been used as organocatalysts for a wide variety of reactions [62]. Wang et al. investigated the use of several 1,2,4-triazolo-annelated chiral NHCs as organocatalysts to catalyze enantioselective aza-MR between primary amines (100) and β-trifluoromethyl-β
  • -arylnitroolefins 101 and the best results (yield 99%, ee 91%) were obtained in the reaction of benzylamine (R1 = Ph) on using the NHC precursor as shown below in the presence of hexafluoroisopropanol (HFIP) as additive along with molecular sieves (4 Å) (Table 23) [63]. The role of HFIP is to act as proton shuttle
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Published 18 Oct 2021

Asymmetric organocatalyzed synthesis of coumarin derivatives

  • Natália M. Moreira,
  • Lorena S. R. Martelli and
  • Arlene G. Corrêa

Beilstein J. Org. Chem. 2021, 17, 1952–1980, doi:10.3762/bjoc.17.128

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  • ]coumarins are formed with good to excellent yields and enantioselectivities (Scheme 14). N-heterocyclic carbenes (NHC) have also been successfully used as organocatalysts, in particular, to obtain coumarin derivatives [47]. In this context, Yetra et al. reported a NHC catalyzed reaction of 2-bromoenals 46
  • with various heterocyclic C–H acids, resulting in the synthesis of coumarin/quinolinone fused dihydropyranones and dihydropyridinones 47. The reaction optimization and the scope and limitations study were carried out using an achiral NHC, but the enantioselective version was also performed using 4
  • -hydroxycoumarin (1) with the chiral catalyst 48, as shown in Scheme 15 [48]. The enantioselective synthesis of dihydrocoumarins 51 from an inverse demand [4 + 2] cycloaddition of ketenes 50 with o-quinone methides 49 using carbene catalyst (NHC) 52 was described by Ye and co-workers [49].This transformation
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Published 03 Aug 2021

A comprehensive review of flow chemistry techniques tailored to the flavours and fragrances industries

  • Guido Gambacorta,
  • James S. Sharley and
  • Ian R. Baxendale

Beilstein J. Org. Chem. 2021, 17, 1181–1312, doi:10.3762/bjoc.17.90

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Published 18 May 2021

Recent advances in palladium-catalysed asymmetric 1,4–additions of arylboronic acids to conjugated enones and chromones

  • Jan Bartáček,
  • Jan Svoboda,
  • Martin Kocúrik,
  • Jaroslav Pochobradský,
  • Alexander Čegan,
  • Miloš Sedlák and
  • Jiří Váňa

Beilstein J. Org. Chem. 2021, 17, 1048–1085, doi:10.3762/bjoc.17.84

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  • (phosphines, NHC-carbenes, bisoxazolines, pyridine-oxazolines, and miscellaneous) is used. Review Catalytic systems based on phosphine ligands A pioneering work on the enantioselective addition of boron-derived carbon nucleophiles to cyclic enones was published by the group of Miyaura et al. in 2005 [32
  • oxidative Heck-type product. The authors stated that as a result of the coordination with PPh3, there is a steric hindrance disfavouring the β-hydride elimination [43]. Catalytic systems based on NHC ligands Historically, the second type of ligands used were N-heterocyclic carbenes (NHC). The first use was
  • reported in a work Shi and co-workers in 2008 who studied the addition of arylboronic acids to 2-cyclohexenone catalysed by Pd complexes of axially chiral NHC carbenes with two other weakly coordinating ligands [44][45]. The complexes with acetates (PdL7a), trifluoroacetates (PdL7b), and diaquo complex
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Published 10 May 2021

Using multiple self-sorting for switching functions in discrete multicomponent systems

  • Amit Ghosh and
  • Michael Schmittel

Beilstein J. Org. Chem. 2020, 16, 2831–2853, doi:10.3762/bjoc.16.233

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  • BPh4− at the cage [Co6(10')4]12+ (SelfSORT-I). Double self-sorting (only structural) Hahn et al. demonstrated for the first time that poly-NHC ligands furnish metallosupramolecular assemblies through narcissistic self-sorting [53]. The one-pot reaction of the tris-NHC ligands 13–15 with different
  • backbones in the presence of Ag2O provided exclusively the three homomeric cylinders [Ag3(13)2]3+, [Ag3(14)2]3+, and [Ag3(15)2]3+ (state: SelfSORT-I in Figure 7). Upon the addition of gold(I) ions, a one-pot transmetalation triggered an exchange of the Ag+ ions for Au+ in the tris-NHC ligand-based cylinders
  • (SelfSORT-II). Such type of transmetalation in metal–NHC complexes with a retention of the individual homomeric supramolecular assemblies has not been reported in literature. Recently, a quantitative and reversible structural interconversion of supramolecular structures was achieved by the inclusion and
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Published 20 Nov 2020

Recent developments in enantioselective photocatalysis

  • Callum Prentice,
  • James Morrisson,
  • Andrew D. Smith and
  • Eli Zysman-Colman

Beilstein J. Org. Chem. 2020, 16, 2363–2441, doi:10.3762/bjoc.16.197

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  • 100 in good yields and enantioselectivities (21 examples for THCs, up to 98:2 er and 10 examples for THIQs, up to 98:2 er). N-Heterocyclic carbene catalysis N-Heterocyclic carbene (NHC) catalysis was first used in combination with photoredox catalysis by Rovis in 2012. They showed that iminium ions
  • 101 could be generated in an oxidative quenching cycle from THIQs 102 using a ruthenium-based photocatalyst and 1,3-dinitrobenzene (DNB) as a sacrificial oxidant (Scheme 13) [51]. These iminium ions could then be intercepted by a Breslow intermediate 103, formed between aldehydes 104 and the NHC
  • catalyst 105, to generate intermediate 106, which can then turn over the NHC and release the desired acylated products 107 in good yields and enantioselectivities (13 examples, up to 96:4 er). There has been little development of enantioselective reactions using NHCs in photocatalysis since this work
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Published 29 Sep 2020

Efficient [(NHC)Au(NTf2)]-catalyzed hydrohydrazidation of terminal and internal alkynes

  • Maximillian Heidrich and
  • Herbert Plenio

Beilstein J. Org. Chem. 2020, 16, 2080–2086, doi:10.3762/bjoc.16.175

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  • Maximillian Heidrich Herbert Plenio Organometallic Chemistry, Technische Universität Darmstadt, Alarich-Weiss-Str. 12, 64287 Darmstadt, Germany 10.3762/bjoc.16.175 Abstract The efficient hydrohydrazidation of terminal (6a–r, 18 examples, 0.1–0.2 mol % [(NHC)Au(NTf2)], T = 60 °C) and internal
  • alkynes (7a–j, 10 examples, 0.2–0.5 mol % [(NHC)Au(NTf2)], T = 60–80 °C) utilizing a complex with a sterically demanding bispentiptycenyl-substituted NHC ligand and the benign reaction solvent anisole, is reported. Keywords: alkyne; gold; homogeneous catalysis; hydrohydrazidation; NHC ligand
  • activity of gold complexes in such reactions tends to be higher, when using sterically demanding ligands (NHC, phosphine) [41]. Recently, the hydrohydrazidation of substituted phenylacetylenes using [(Ph3P)Au(NTf2)] as the catalyst was reported by Rassadin, Kukushkin et al. [42]. Catalyst loadings of 6 mol
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Published 26 Aug 2020

Metal-free synthesis of phosphinoylchroman-4-ones via a radical phosphinoylation–cyclization cascade mediated by K2S2O8

  • Qiang Liu,
  • Weibang Lu,
  • Guanqun Xie and
  • Xiaoxia Wang

Beilstein J. Org. Chem. 2020, 16, 1974–1982, doi:10.3762/bjoc.16.164

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  • sciences over the last few years [1][4][5]. In general, chroman-4-one derivatives could be obtained via a polarity reversal strategy enabled by the N-heterocyclic carbene (NHC)-catalyzed intramolecular Stetter reaction [6][7][8]. Besides, chroman-4-one derivatives were also constructed via intramolecular
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Published 12 Aug 2020

Synergy between supported ionic liquid-like phases and immobilized palladium N-heterocyclic carbene–phosphine complexes for the Negishi reaction under flow conditions

  • Edgar Peris,
  • Raúl Porcar,
  • María Macia,
  • Jesús Alcázar,
  • Eduardo García-Verdugo and
  • Santiago V. Luis

Beilstein J. Org. Chem. 2020, 16, 1924–1935, doi:10.3762/bjoc.16.159

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  • , Janssen-Cilag, S.A., C/ Jarama 75A, Toledo, Spain 10.3762/bjoc.16.159 Abstract The combination of supported ionic liquids and immobilized NHC–Pd–RuPhos led to active and more stable systems for the Negishi reaction under continuous flow conditions than those solely based on NHC–Pd–RuPhos. The fine tuning
  • of the NHC–Pd catalyst and the SILLPs is a key factor for the optimization of the release and catch mechanism leading to a catalytic system easily recoverable and reusable for a large number of catalytic cycles enhancing the long-term catalytic performance. Keywords: immobilized catalyst; Negishi
  • cross-coupling; NHC complex; palladium; supported ionic liquid; Introduction N-heterocyclic carbenes (NHCs) are known as efficient coordination ligands for different types of metals. The main feature of NHC complexes is their structural tunability [1]. Thus, their catalytic efficiency can be easily
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Published 06 Aug 2020

When metal-catalyzed C–H functionalization meets visible-light photocatalysis

  • Lucas Guillemard and
  • Joanna Wencel-Delord

Beilstein J. Org. Chem. 2020, 16, 1754–1804, doi:10.3762/bjoc.16.147

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  • merging C–H activation and photocatalysis while using a single metal catalyst. In this case, an original Rh–NHC complex was used for the ortho-directed C–H borylation of phenylpyridine substrates (Figure 40) [102]. As previously, the irradiation with visible light allowed performing this challenging
  • -selective C–H alkylations by the nature of the metal-based photoactive species (Figure 41). Indeed, the NHC–Rh complex is believed to be photoactive after coordination of the phenylpyridine substrate. The generated coordination complex becomes excited after the absorption of visible light and thus undergoes
  • active NHC–Rh(I) complex. The potential of the above-mentioned reactions is particularly interesting as indeed, a unique, double reactivity might be attributed to a single precatalyst with the in situ formation of photoactive intermediates. Remarkably, the generated metallaphotoredox catalyst is able to
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Published 21 Jul 2020

NHC-catalyzed enantioselective synthesis of β-trifluoromethyl-β-hydroxyamides

  • Alyn T. Davies,
  • Mark D. Greenhalgh,
  • Alexandra M. Z. Slawin and
  • Andrew D. Smith

Beilstein J. Org. Chem. 2020, 16, 1572–1578, doi:10.3762/bjoc.16.129

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  • Alyn T. Davies Mark D. Greenhalgh Alexandra M. Z. Slawin Andrew D. Smith EaStCHEM, School of Chemistry, University of St Andrews, North Haugh, St Andrews, Fife KY16 9ST, United Kingdom 10.3762/bjoc.16.129 Abstract The N-heterocyclic carbene (NHC)-catalyzed formal [2 + 2] cycloaddition between α
  • ][44][45] in the presence of an oxidant. As representative examples of the use of azolium enolates in reactions with trifluoroacetophenone derivatives, Ye and co-workers have shown that using disubstituted ketenes as azolium enolate precursors and NHC precatalyst 1 allowed access to trifluoromethyl
  • -substituted β-lactone products in a high yield, diastereo-, and enantioselectivity (Figure 2A) [46]. Chi and co-workers have reported limited examples of oxidative [2 + 2] cycloadditions using hydrocinnamaldehyde as an azolium enolate precursor and the NHC precatalyst 2, giving β-lactone products in high
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Published 30 Jun 2020

Synthesis of esters of diaminotruxillic bis-amino acids by Pd-mediated photocycloaddition of analogs of the Kaede protein chromophore

  • Esteban P. Urriolabeitia,
  • Pablo Sánchez,
  • Alexandra Pop,
  • Cristian Silvestru,
  • Eduardo Laga,
  • Ana I. Jiménez and
  • Carlos Cativiela

Beilstein J. Org. Chem. 2020, 16, 1111–1123, doi:10.3762/bjoc.16.98

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  • (m, 1H, H5, C6H3F), 6.40 (d, J = 15.7 Hz, 1H, Hα), 6.01 (s, 1H, cyclobutane), 4.00 (s, broad, 3H, OMe, CO2Me cyclobutane), 3.88 (s, 3H, OMe, Ar–CO2Me); 13C{1H} NMR (75.47 MHz, CDCl3) δ 172.3 (s, CO2Me cyclobutane), 167.9 (s, Ar-CO2Me), 166.6 (s, NHC=O), 161.3 (d, 1JCF = 248.0 Hz, C–F, C6H3F), 142.8
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Published 25 May 2020
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