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Search for "nitrile" in Full Text gives 262 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.

Fluorinated phenylalanines: synthesis and pharmaceutical applications

  • Laila F. Awad and
  • Mohammed Salah Ayoup

Beilstein J. Org. Chem. 2020, 16, 1022–1050, doi:10.3762/bjoc.16.91

Graphical Abstract
  • nitrile 48a with 30% HCl aq/acetic acid, gave the 4-fluorophenylalanine·HCl 49a in a good overall yield (67%) [47] (Scheme 11). 1.4. Hydrolysis of Erlenmeyer’s azalactone A multistep Erlenmeyer azalactone synthesis was reported as an important method for the synthesis of fluorinated α-amino acids 53a–h
  • (126). Then, reaction of 127 (1.0 mmol) with 1.5/1.0 equiv of diethylaluminum cyanide (Et2AlCN)/iPrOH at −78 °C in THF gave nitrile 128. Deprotection of the latter, followed by hydrolysis of the nitrile group afforded syn-(2S,3S)-(+)-3-fluorophenylalanine (129) [65] (Scheme 28) . 2.3. Multistep
  • ] (Scheme 41). An alternative approach to the difluorinated compound 168a was achieved by the condensation of 164a with (S)-1-phenylethylamine (169), to give the imine 170. Heating of imine 170 with TMSCN in the presence of zinc iodide [82] generated the nitrile 171 as a 1:1 mixture of diastereoisomers
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Published 15 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

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  • using 4 mol % of tetra-n-butylammonium fluoride (TBAF) as an activator of TMSCN (conditions B). Following this second protocol, the primary α-aminonitriles were rapidly prepared in relevant yields (up to 87%) and converted to the corresponding α-amino acids by hydrolysis of the nitrile (Scheme 57
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Published 06 May 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
  • attached to the triflate bearing carbon. In this way, different classes of substrates bearing either a nitrile (17) or ethyl ester (21) easily underwent conversion to the corresponding silylated products 18–20 in moderate to good yields (Scheme 5). This method was extended to the use of enantiomerically
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Published 15 Apr 2020

Synthesis of organic liquid crystals containing selectively fluorinated cyclopropanes

  • Zeguo Fang,
  • Nawaf Al-Maharik,
  • Peer Kirsch,
  • Matthias Bremer,
  • Alexandra M. Z. Slawin and
  • David O’Hagan

Beilstein J. Org. Chem. 2020, 16, 674–680, doi:10.3762/bjoc.16.65

Graphical Abstract
  • relative to other polar substituents such as nitrile and ester groups, and this reduces intermolecular interactions leading to lower viscosities and thus increased life time reliability [4][5]. A significant effort has been devoted to the development of liquid crystals with either positive or negative
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Published 14 Apr 2020

Cascade trifluoromethylthiolation and cyclization of N-[(3-aryl)propioloyl]indoles

  • Ming-Xi Bi,
  • Shuai Liu,
  • Yangen Huang,
  • Xiu-Hua Xu and
  • Feng-Ling Qing

Beilstein J. Org. Chem. 2020, 16, 657–662, doi:10.3762/bjoc.16.62

Graphical Abstract
  • effect of the substitution on the indole ring. Both electron-donating and withdrawing groups at different positions of the indole ring produced the bis(trifluoromethylthiolated) products 2a–o in moderate to good yields. A wide range of functionalities such as alkyl, alkoxy, nitro, nitrile, ester
  • were subjected to the standard conditions, the cascade trifluoromethylthiolation and cyclization occurred to yield trifluoromethylthiolated pyrrolo[1,2-a]indol-3-ones (4a–d) in moderate yields (Scheme 3). The functionalities including alkyl, aryl, nitrile, and acyl were also well tolerated in this
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Published 08 Apr 2020

Architecture and synthesis of P,N-heterocyclic phosphine ligands

  • Wisdom A. Munzeiwa,
  • Bernard Omondi and
  • Vincent O. Nyamori

Beilstein J. Org. Chem. 2020, 16, 362–383, doi:10.3762/bjoc.16.35

Graphical Abstract
  • the quinazoline ring (Scheme 17) and the phosphine was introduced via metal-catalyzed phosphorylation. The ligands were synthesized in eight steps with relatively good yield. The reaction between substituted nitrile derivatives 87 and anthranilic acid (88) catalyzed by sodium methoxide formed
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Published 12 Mar 2020

The use of isoxazoline and isoxazole scaffolding in the design of novel thiourea and amide liquid-crystalline compounds

  • Itamar L. Gonçalves,
  • Rafaela R. da Rosa,
  • Vera L. Eifler-Lima and
  • Aloir A. Merlo

Beilstein J. Org. Chem. 2020, 16, 175–184, doi:10.3762/bjoc.16.20

Graphical Abstract
  • , 8, 9, 12 and 13 were then prepared by [3 + 2]-1,3-dipolar cycloaddition of nitrile oxide (ArCNO) formed in situ from oximes and a number of alkenes as dipolarophiles, to yield the precursors of the cycloadducts isoxazolines 2, 7 and 11 regioselectively. The cycloadducts were subjected to SnCl2
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Published 06 Feb 2020

Efficient method for propargylation of aldehydes promoted by allenylboron compounds under microwave irradiation

  • Jucleiton J. R. Freitas,
  • Queila P. S. B. Freitas,
  • Silvia R. C. P. Andrade,
  • Juliano C. R. Freitas,
  • Roberta A. Oliveira and
  • Paulo H. Menezes

Beilstein J. Org. Chem. 2020, 16, 168–174, doi:10.3762/bjoc.16.19

Graphical Abstract
  • or nitrile group were used, the corresponding products 2q and 2r were obtained in good yields. The use of a heteroaromatic or an aliphatic aldehyde as substrates under the optimized conditions gave the corresponding homopropargylic alcohols 2s,t in moderate yields. The development of a solvent-free
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Published 04 Feb 2020

Synthesis of 3-alkenylindoles through regioselective C–H alkenylation of indoles by a ruthenium nanocatalyst

  • Abhijit Paul,
  • Debnath Chatterjee,
  • Srirupa Banerjee and
  • Somnath Yadav

Beilstein J. Org. Chem. 2020, 16, 140–148, doi:10.3762/bjoc.16.16

Graphical Abstract
  • tolerated several functional groups, including bromine and nitrile units, which provide ample scope for further manipulation of the products from the perspective of medicinal chemistry. The catalyst can be easily recovered and recycled in a colloidal solid form, enabling catalytic recycling and reusability
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Published 29 Jan 2020

A green, economical synthesis of β-ketonitriles and trifunctionalized building blocks from esters and lactones

  • Daniel P. Pienaar,
  • Kamogelo R. Butsi,
  • Amanda L. Rousseau and
  • Dean Brady

Beilstein J. Org. Chem. 2019, 15, 2930–2935, doi:10.3762/bjoc.15.287

Graphical Abstract
  • environmentally unfriendly transition-metal-based reactions. Acylations of in situ-generated nitrile anions with esters to produce β-ketonitriles were first reported long ago, for example by using sodium methoxide [2], sodium ethoxide [3] or sodium amide [4][5]. The reaction was found to proceed more efficiently
  • when using sodium amide as the base [5], although the inherent risks of employing explosive sodium amide in synthesis are well known [6] and amidine side-product formation was observed at times through reaction of the nucleophilic amide base with nitrile. Furthermore, clearly two equivalents of base
  • (and nitrile) were necessary to drive the reactions to completion as the acylated product is more acidic than the nitrile starting material. More recently, ester or Weinreb amide reactions with acetonitrile using lithium bases at low temperature [7], or similarly NaH at high temperatures [8], have been
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Published 06 Dec 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

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  • involved the synthesis of precursor (+)-198 from phenylacetic acid and (−)-α-PEA via sequential amidation, reduction and Pictet–Spengler cyclization reactions. The key anodic oxidation in the presence of NaCN converted (+)-198 to α-amino nitrile (+)-199 with excellent diastereoselectivity. Upon further
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Published 13 Nov 2019

Functionalization of 4-bromobenzo[c][2,7]naphthyridine via regioselective direct ring metalation. A novel approach to analogues of pyridoacridine alkaloids

  • Benedikt C. Melzer,
  • Alois Plodek and
  • Franz Bracher

Beilstein J. Org. Chem. 2019, 15, 2304–2310, doi:10.3762/bjoc.15.222

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  • bromo substituent of the appropriate substrates 20a or 20b should converted into the respective organomagnesium product by bromine–magnesium exchange. In an expected subsequent Parham-type ring-closing reaction [33] the nucleophilic carbon at position 4 should trap the ester (or nitrile) group to lead
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Published 26 Sep 2019

Regioselective Pd-catalyzed direct C1- and C2-arylations of lilolidine for the access to 5,6-dihydropyrrolo[3,2,1-ij]quinoline derivatives

  • Hai-Yun Huang,
  • Haoran Li,
  • Thierry Roisnel,
  • Jean-François Soulé and
  • Henri Doucet

Beilstein J. Org. Chem. 2019, 15, 2069–2075, doi:10.3762/bjoc.15.204

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  • -arylated lilolidines were generally obtained in high regioselectivities and in good yields using aryl bromides as easily available aryl sources, acetates as inexpensive bases and PdCl(C3H5)(dppb) as air-stable catalyst. The reaction tolerated a wide variety of useful functional groups such as nitrile
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Published 29 Aug 2019

Recent advances on the transition-metal-catalyzed synthesis of imidazopyridines: an updated coverage

  • Gagandeep Kour Reen,
  • Ashok Kumar and
  • Pratibha Sharma

Beilstein J. Org. Chem. 2019, 15, 1612–1704, doi:10.3762/bjoc.15.165

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Published 19 Jul 2019

A novel three-component reaction between isocyanides, alcohols or thiols and elemental sulfur: a mild, catalyst-free approach towards O-thiocarbamates and dithiocarbamates

  • András György Németh,
  • György Miklós Keserű and
  • Péter Ábrányi-Balogh

Beilstein J. Org. Chem. 2019, 15, 1523–1533, doi:10.3762/bjoc.15.155

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  • -diimidazole or di-2-pyridyl thionocarbonate [57][58]. Decomposition of dithiocarbamate salts or thiocarbamates with various reagents offers a good alternative [59][60][61][62] as well, however, this approach first requires the synthesis of the appropriate precursor. Nitrile oxides react with thiourea to
  • afford isothiocyanate and harmless urea [63][64][65], but one should note that the instability of the nitrile oxides leads to many byproducts, turning this approach less attractive. The synthesis of isothiocyanates starting from isonitriles involves sulfur-containing reagents such as thallium
  • , we have turned our attention to different benzylic alcohols that could be utilized to further examine the functional group tolerance of the reaction. Notably, chlorine, bromine and iodine substituents were compatible with the transformation, providing 3m, 3n, 3r and 3s in 81–89% yield. The nitrile
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Published 10 Jul 2019

Introduction of an isoxazoline unit to the β-position of porphyrin via regioselective 1,3-dipolar cycloaddition reaction

  • Xiujun Liu,
  • Xiang Ma and
  • Yaqing Feng

Beilstein J. Org. Chem. 2019, 15, 1434–1440, doi:10.3762/bjoc.15.143

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  • Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072, China 10.3762/bjoc.15.143 Abstract Isoxazoline-linked porphyrins have been synthesized by a regioselective 1,3-dipolar cycloaddition reaction between vinylporphyrin 2 and nitrile oxides. The steric interaction directed the
  • ; isoxazoline; macrocycles; nitrile oxide; porphyrin; Introduction In nature, porphyrin-type compounds play a prominent role in life [1]. It is well known that certain vital functions, like O2 transport, photosynthesis etc. depend on the action of porphyrin–metal complexes [2][3][4][5]. Inspired by the natural
  • -generated nitrile oxide, which showed inferior selectivity and afforded regio-/stereoisomers [43]. NMR analysis assisted the identification of various isomeric isoxazoline-linked chlorin products. Here, we would like to report an artificial vinylporphyrin 2, which has been designed to control the
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Published 28 Jun 2019

Multicomponent reactions (MCRs): a useful access to the synthesis of benzo-fused γ-lactams

  • Edorta Martínez de Marigorta,
  • Jesús M. de Los Santos,
  • Ana M. Ochoa de Retana,
  • Javier Vicario and
  • Francisco Palacios

Beilstein J. Org. Chem. 2019, 15, 1065–1085, doi:10.3762/bjoc.15.104

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  • -component reaction, to afford isoindolinones 53 substituted with nitrile or carboxamide groups (Scheme 15, method A) [93]. Trimethylsilylcyanide (52), and benzyl-, alkyl- and allylamines 2 were reacted with 2-formylbenzoic acid (33) in the presence of OSU-6, a mesoporous silica performing as a green Lewis
  • acid catalyst for this transformation. At room temperature, the product of this environmentally friendly Strecker reaction is nitrile derivative 53 (R2 = CN, Scheme 15, method A), while at reflux carboxamide 53 (R2 = CONH2, Scheme 15, method A) is obtained. Notoriously, aromatic amines 2 did not work
  • oxidation of this radical would give rise to the corresponding cation 74, which would add to the nucleophilic nitrile 70. Intramolecular nucleophilic attack of the carboxy group in 75 followed by rearrangement of intermediate 76 delivered isoindolinone derivatives 71. Ortho-functionalized benzoic acids have
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Published 08 May 2019

Novel (2-amino-4-arylimidazolyl)propanoic acids and pyrrolo[1,2-c]imidazoles via the domino reactions of 2-amino-4-arylimidazoles with carbonyl and methylene active compounds

  • Victoria V. Lipson,
  • Tetiana L. Pavlovska,
  • Nataliya V. Svetlichnaya,
  • Anna A. Poryvai,
  • Nikolay Yu. Gorobets,
  • Erik V. Van der Eycken,
  • Irina S. Konovalova,
  • Svetlana V. Shiskina,
  • Alexander V. Borisov,
  • Vladimir I. Musatov and
  • Alexander V. Mazepa

Beilstein J. Org. Chem. 2019, 15, 1032–1045, doi:10.3762/bjoc.15.101

Graphical Abstract
  • CN at 2250 cm−1. In addition, there are characteristic bands at 1664–1668 cm−1, which may include both C=C bond and the exocyclic C=N bond. Fluctuations of endocyclic C=N fragments are observed at 1584 cm−1. Thus, at least one nitrile and one NH2 group are present in the obtained compounds. The 1H
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Published 06 May 2019

Heck- and Suzuki-coupling approaches to novel hydroquinone inhibitors of calcium ATPase

  • Robert J. Kempton,
  • Taylor A. Kidd-Kautz,
  • Soizic Laurenceau and
  • Stefan Paula

Beilstein J. Org. Chem. 2019, 15, 971–975, doi:10.3762/bjoc.15.94

Graphical Abstract
  • -step sequence of oxidation employing ammonium cerium(IV) nitrate (CAN) [20] to afford the corresponding quinone (not shown), followed by reduction with sodium hydrosulfite [21]. With the nitrile in hand, we next attempted to reduce that functional group to an amine to which a leucine moiety could be
  • , followed by addition of bromide 5a, potassium phosphate and PdCl2(dppf)2 in DMF at 85 °C for 3.5 h gave the coupled product 10 in 47–63% yields (Scheme 3). In contrast to the case of the Heck coupling products (6 and 8, Scheme 2), nitrile 10 underwent facile reduction with lithium aluminium hydride. The
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Published 24 Apr 2019

Efficient synthesis of pyrazolopyridines containing a chromane backbone through domino reaction

  • Razieh Navari,
  • Saeed Balalaie,
  • Saber Mehrparvar,
  • Fatemeh Darvish,
  • Frank Rominger,
  • Fatima Hamdan and
  • Sattar Mirzaie

Beilstein J. Org. Chem. 2019, 15, 874–880, doi:10.3762/bjoc.15.85

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  • hydrogen in intermediate B, it is possible to form chromonyl-malononitrile conjugated system C and to eliminate the phenylhydrazine. Intermediate C is a highly potent Michael acceptor that may allow the addition of hydrazine to the nitrile group resulting in intermediate D that after elimination of water
  • products 5a–d were not formed. The reaction mechanism is shown in Scheme 2. The chemical structures of the products 5a–d are shown in Figure 4. Usually, to activate the nitrile group for cyclization reaction, the existence of Lewis acid, the addition of organolithium reagents or metal
  • hexamethylenedisalazane is necessary. However, in this approach, the nucleophilic addition on the nitrile group and the cyclization was achieved without the addition of a catalyst [44]. This reaction possesses a highly atom economical character and requires only triethylamine (40 mol %) as a base in EtOH and provides
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Published 11 Apr 2019

The LANCA three-component reaction to highly substituted β-ketoenamides – versatile intermediates for the synthesis of functionalized pyridine, pyrimidine, oxazole and quinoxaline derivatives

  • Tilman Lechel,
  • Roopender Kumar,
  • Mrinal K. Bera,
  • Reinhold Zimmer and
  • Hans-Ulrich Reissig

Beilstein J. Org. Chem. 2019, 15, 655–678, doi:10.3762/bjoc.15.61

Graphical Abstract
  • to β-ketoenamides that are uniquely functionalized alkenes and suitable for a variety of subsequent reactions, in particular in heterocyclic synthesis. This LANCA three-component reaction (LA = lithiated alkoxyallene, N = nitrile, CA = carboxylic acid) was observed for the first time by Oliver Flögel
  • in the three-component reaction. The products KE36–39 are derived from the O-protected nitrile obtained from (S)-lactic acid [35][36]. This chiral acid itself was incorporated as third component resulting in β-ketoenamides KE39–41. There is no indication of an erosion of the enantiopurity and the
  • reasonable overall yields (Scheme 20) [30]. This pathway via the pyrimidine N-oxides represents a good alternative to the direct oxidation of the 4-methyl group by selenium dioxide (see Scheme 11). The subsequent transformation of the aldehyde PM71 to the oxime followed by dehydration afforded nitrile PM72
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Published 13 Mar 2019

Cross metathesis-mediated synthesis of hydroxamic acid derivatives

  • Shital Kumar Chattopadhyay,
  • Subhankar Ghosh and
  • Suman Sil

Beilstein J. Org. Chem. 2018, 14, 3070–3075, doi:10.3762/bjoc.14.285

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  • nitrile functionalities [19][20] have been shown to yield shorter routes to compounds of interest as well as for green chemical applications [21][22]. Hydroxamates belong to a class of valuable biologically relevant compounds of proven record of utility. For example, the hydroxamate SAHA (1, Figure 1) [23
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Published 17 Dec 2018

Nucleofugal behavior of a β-shielded α-cyanovinyl carbanion

  • Rudolf Knorr and
  • Barbara Schmidt

Beilstein J. Org. Chem. 2018, 14, 3018–3024, doi:10.3762/bjoc.14.281

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  • –30 °C under argon gas cover during the addition of n-BuLi (1.05 mmol) in hexane (0.47 mL). The created LDA (up to 1.05 mmol) solution was treated with the solid nitrile 1 (200 mg, 0.95 mmol) and stirred further at rt till 1 was completely dissolved, whereupon the carbonyl compound (1.24 mmol, neat or
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Published 11 Dec 2018

Reactions of 3-(p-substituted-phenyl)-5-chloromethyl-1,2,4-oxadiazoles with KCN leading to acetonitriles and alkanes via a non-reductive decyanation pathway

  • Akın Sağırlı and
  • Yaşar Dürüst

Beilstein J. Org. Chem. 2018, 14, 3011–3017, doi:10.3762/bjoc.14.280

Graphical Abstract
  • that are generally obtained by the reaction of benzyl halides with appropriate cyanating agents such as KCN [14], TMSCN [15], K4(Fe(CN)6 [16]. Deprotonation of the α-carbon (adjacent to nitrile) by strong bases, especially lithiated ones, resulted in an anionic species that easily undergoes a
  • products 4f and 4g, respectively, in a shorter reaction time (Table 2, entries 6 and 7). However, due to the replacement of the nitrile group with hydrogen after decyanation in product 4, the methylenic protons and the methinic proton resonates at around 4–5 ppm as doublets and 5 ppm as pentet
  • . Then, the acidic hydrogen adjacent to the nitrile group in the intermediate product is sequentially abstracted by a CN− anion with the extrusion of an HCN molecule and a carbanion alpha to the nitrile group bearing a 1,2,4-oxadiazole ring is formed. The resulted carbanion undergoes a substitution
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Published 10 Dec 2018

1,8-Bis(dimethylamino)naphthyl-2-ketimines: Inside vs outside protonation

  • A. S. Antonov,
  • A. F. Pozharskii,
  • P. M. Tolstoy,
  • A. Filarowski and
  • O. V. Khoroshilova

Beilstein J. Org. Chem. 2018, 14, 2940–2948, doi:10.3762/bjoc.14.273

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  • Synthesis of DMAN-ortho-ketimines and their cations Target compounds 4a–7a were synthesised by techniques previously developed in our laboratory (Scheme 4) [7][8]. Compounds 4a–6a were obtained by the treatment of the ortho-lithium derivative 8 with the corresponding nitrile (path a). Unfortunately, the
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Published 28 Nov 2018
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