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Search for "nitrile" in Full Text gives 261 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.

Synthesis of phenanthridines via a novel photochemically-mediated cyclization and application to the synthesis of triphaeridine

  • Songeziwe Ntsimango,
  • Kennedy J. Ngwira,
  • Moira L. Bode and
  • Charles B. de Koning

Beilstein J. Org. Chem. 2021, 17, 2340–2347, doi:10.3762/bjoc.17.152

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  • reported by Rodrıguez and Walton we envisaged that under these photochemcial conditions, intermediate 8 would be formed. Contrary to the expected results, in our labs exposure of oxime 7 to UV irradiation yielded phenanthridine 9 as the main product alongside the nitrile 10 in lower yields [13]. We
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Published 08 Sep 2021

Synthesis of O6-alkylated preQ1 derivatives

  • Laurin Flemmich,
  • Sarah Moreno and
  • Ronald Micura

Beilstein J. Org. Chem. 2021, 17, 2295–2301, doi:10.3762/bjoc.17.147

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  • -bis(trimethylsilyl)acetamide [34], simultaneous tritylation of N9 and the N2 atoms was achieved using 4,4'-dimethoxytrityl chloride in pyridine. The obtained derivative 4 was amenable to nitrile reduction using diisobutylaluminium hydride (DIBAL-H) in dichloromethane at −78 °C, followed by workup with
  • )), 154.8 (C(4)), 146.3 (C(2)), 142.15 & 138.4 & 134.3 (C(aromatic, DMTr)), 133.1 (C(8)), 131.4 & 130.4 & 130.3 & 130.2 & 129.80 & 129.1 & 127.8 & 127.5 & 127.4 & 126.4 (C(aromatic, DMTr)), 115.8 (C(5)/C(7)), 113.3 & 113.1 & 112.7 (C(aromatic, DMTr)), 99.2 (C(5)/C(7)), 83.1 (CN(nitrile)), 76.1 & 70.5 (CAr3
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Published 02 Sep 2021

Enantioenriched α-substituted glutamates/pyroglutamates via enantioselective cyclopropenimine-catalyzed Michael addition of amino ester imines

  • Zara M. Seibel,
  • Jeffrey S. Bandar and
  • Tristan H. Lambert

Beilstein J. Org. Chem. 2021, 17, 2077–2084, doi:10.3762/bjoc.17.134

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  • handles for derivatization and so represent important achievements for this method. In terms of additional functionality, we found that a thioether substrate could be engaged with reasonably good efficiency and enantioselectivity (Table 2, entry 11). On the other hand, while a nitrile was compatible with
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Published 17 Aug 2021

A study on selective transformation of norbornadiene into fluorinated cyclopentane-fused isoxazolines

  • Zsanett Benke,
  • Attila M. Remete and
  • Loránd Kiss

Beilstein J. Org. Chem. 2021, 17, 2051–2066, doi:10.3762/bjoc.17.132

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  • Abstract This work presents an examination of the selective functionalization of norbornadiene through nitrile oxide 1,3-dipolar cycloaddition/ring-opening metathesis (ROM)/cross-metathesis (CM) protocols. Functionalization of commercially available norbornadiene provided novel bicyclic scaffolds with
  • the CM transformations with the goal of exploring substrate and steric effects, catalyst influence and chemodifferentiation of the olefin bonds furnishing the corresponding functionalized, fluorine-containing isoxazoline derivatives. Keywords: functionalization; metathesis; nitrile oxide
  • selective functionalization of readily available norbornadiene across nitrile oxide cycloaddition/ROM/CM protocols in view of the access of various fluorine-containing molecular entities as well as to explore the chemical behavior of olefin bonds in the reaction with some fluorinated alkene derivatives in
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Published 13 Aug 2021

Regioselective N-alkylation of the 1H-indazole scaffold; ring substituent and N-alkylating reagent effects on regioisomeric distribution

  • Ryan M. Alam and
  • John J. Keating

Beilstein J. Org. Chem. 2021, 17, 1939–1951, doi:10.3762/bjoc.17.127

Graphical Abstract
  • , indazole ring-closure [10][11]. For example, several reports have highlighted the use of N-alkyl or N-arylhydrazines in the regioselective synthesis of 1H-indazoles, from the corresponding ortho-haloaryl carbonyl or nitrile, in good to excellent yield (Scheme 1) [12][13][14]. Alternative strategies to
  • presence of an electronegative nitrile group at the indazole C-3 position (20) provided only modest N-1 regioselectivity, under both conditions A and B (N-1 (41):N-2 (42) = 3.4:1 and 5.2:1, respectively) (Table 2, entry 9). Remarkably, unlike methyl ester 9 (vide supra), indazoles 12, 13, 15–18, and 20 all
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Published 02 Aug 2021

On the application of 3d metals for C–H activation toward bioactive compounds: The key step for the synthesis of silver bullets

  • Renato L. Carvalho,
  • Amanda S. de Miranda,
  • Mateus P. Nunes,
  • Roberto S. Gomes,
  • Guilherme A. M. Jardim and
  • Eufrânio N. da Silva Júnior

Beilstein J. Org. Chem. 2021, 17, 1849–1938, doi:10.3762/bjoc.17.126

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Published 30 Jul 2021

Chemical synthesis of C6-tetrazole ᴅ-mannose building blocks and access to a bioisostere of mannuronic acid 1-phosphate

  • Eleni Dimitriou and
  • Gavin J. Miller

Beilstein J. Org. Chem. 2021, 17, 1527–1532, doi:10.3762/bjoc.17.110

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  • mannuronic acid building blocks, appropriately modified at the carboxylate C6 position with a bioisosteric tetrazole. Thioglycosides containing a protected C6-tetrazole are accessed from a C6-nitrile, through dipolar cycloaddition using NaN3 with n-Bu2SnO. We also demonstrate access to orthogonally C4
  • repeated attempts [14]. TLC and NMR analysis consistently indicated no conversion of 4, even after stirring at 80 °C in MeCN for 48 hours. We therefore proposed an alternative route to 5, directly from reaction of a C6 nitrile with NaN3, obviating the need for intermediate cyanoacetamide formation (Scheme
  • at C4 with TBSOTf in excellent yield (87%). C6-nitrile 9 was then successfully converted into C6-tetrazole 5 in 51% yield using TMSN3 and a catalytic amount of Bu2SnO [15]. This method was recently utilised successfully by Bräse and colleagues for ᴅ-gluco-configured C6-tetrazoles in their synthesis
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Published 05 Jul 2021

A straightforward conversion of 1,4-quinones into polycyclic pyrazoles via [3 + 2]-cycloaddition with fluorinated nitrile imines

  • Greta Utecht-Jarzyńska,
  • Karolina Nagła,
  • Grzegorz Mlostoń,
  • Heinz Heimgartner,
  • Marcin Palusiak and
  • Marcin Jasiński

Beilstein J. Org. Chem. 2021, 17, 1509–1517, doi:10.3762/bjoc.17.108

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  • -8057 Zurich, Switzerland Department of Physical Chemistry, Faculty of Chemistry, University of Lodz, Pomorska 163/165, 90236 Łódź, Poland 10.3762/bjoc.17.108 Abstract In-situ-generated N-aryl nitrile imines derived from trifluoroacetonitrile efficiently react with polycyclic 1,4-quinones, yielding
  • naphthoquinone-derived products and low-intensity bands in the visible region (≈400 nm) for the anthraquinone series. Keywords: [3 + 2]-cycloadditions; fluorinated compounds; fused pyrazoles; N-heterocycles; nitrile imines; 1,4-quinones; Introduction The 1,4-quinone scaffold belongs to the most important
  • , [3 + 2]-cycloadditions leading to five-membered heterocycles are less often employed in spite of the high dipolarophilicity of the α,β-unsaturated diketone system [6][7][8][9]. Notably, in the already reported reactions of propargylic 1,3-dipoles, such as nitrile oxides or nitrile ylides, with 1,4
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Published 28 Jun 2021

One-step synthesis of imidazoles from Asmic (anisylsulfanylmethyl isocyanide)

  • Louis G. Mueller,
  • Allen Chao,
  • Embarek AlWedi and
  • Fraser F. Fleming

Beilstein J. Org. Chem. 2021, 17, 1499–1502, doi:10.3762/bjoc.17.106

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  • Substituted imidazoles are readily prepared by condensing the versatile isocyanide Asmic, anisylsulfanylmethylisocyanide, with nitrogenous π-electrophiles. Deprotonating Asmic with lithium hexamethyldisilazide effectively generates a potent nucleophile that efficiently intercepts nitrile and imine
  • to imidazoles [11][12], the condensation of metalated isocyanides with nitrogenous π-electrophiles is distinguished by excellent efficiency and modularity. Deprotonating an isocyanide 1 affords an isocyanide-stabilized anion 2 whose condensation with an imidate or nitrile generates a transient imine
  • fewer steps on at least 20 g scale [18], applicable for the synthesis of several heterocycles [19][20], and able to generate imidazoles from a broad array of nitrile and imidate electrophiles. Results and Discussion Exploratory deprotonation of Asmic (5) with BuLi followed by addition of butyronitrile
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Published 24 Jun 2021

Heterogeneous photocatalytic cyanomethylarylation of alkenes with acetonitrile: synthesis of diverse nitrogenous heterocyclic compounds

  • Guanglong Pan,
  • Qian Yang,
  • Wentao Wang,
  • Yurong Tang and
  • Yunfei Cai

Beilstein J. Org. Chem. 2021, 17, 1171–1180, doi:10.3762/bjoc.17.89

Graphical Abstract
  • loss of photocatalytic activity when applied in the cyanomethylarylation of N-arylallylamine 1a with acetonitrile. We also utilized this strategy to test n-butyl nitrile under the standard conditions. As shown in Scheme 6a, the corresponding oxindole 11 was obtained in 45% yield. The synthetic utility
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Published 17 May 2021

Synthetic accesses to biguanide compounds

  • Oleksandr Grytsai,
  • Cyril Ronco and
  • Rachid Benhida

Beilstein J. Org. Chem. 2021, 17, 1001–1040, doi:10.3762/bjoc.17.82

Graphical Abstract
  • nucleophilic amines, which led to undesired side reactions on the terminal amine of the cyanoguanidine. This issue was partly solved by using TMSCl to activate the nitrile function of the cyanoguanidine, along with shortening the reaction times to 10 min. Recently, this approach was used under classical
  • Štrukil et al. who reported the addition of aniline hydrochloride to N1-cyano-N2,N3-diisopropylguanidine in water at 125 °C within 30 min [48]. In this case, the desired N1,N4,N5-trisubstituted product was obtained in gratifying 89% yield (Scheme 17B). The activation of the nitrile group of
  • functions and products formed. Addition of amines to dicyanamide (pathway b) The second main route to synthesize biguanides relies on the use of sodium dicyanamide by double addition of amines on the two nitrile groups. The first synthesis following this pathway was described by Rose et al. in 1956 for the
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Published 05 May 2021

Microwave-assisted multicomponent reactions in heterocyclic chemistry and mechanistic aspects

  • Shivani Gulati,
  • Stephy Elza John and
  • Nagula Shankaraiah

Beilstein J. Org. Chem. 2021, 17, 819–865, doi:10.3762/bjoc.17.71

Graphical Abstract
  • adduct B. Adduct B then undergoes in situ cyclization through an intramolecular addition of nitrogen on amide which acts as a nucleophile to the nitrile and give intermediate C. The tautomerization of the imino to an amino group and subsequent auto-oxidation followed by aromatization affords the required
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Published 19 Apr 2021

Synthesis of N-perfluoroalkyl-3,4-disubstituted pyrroles by rhodium-catalyzed transannulation of N-fluoroalkyl-1,2,3-triazoles with terminal alkynes

  • Olga Bakhanovich,
  • Viktor Khutorianskyi,
  • Vladimir Motornov and
  • Petr Beier

Beilstein J. Org. Chem. 2021, 17, 504–510, doi:10.3762/bjoc.17.44

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  • general trend in the efficiency of the reaction or product selectivity was observed. Hex-5-ynenitrile was used in the transannulation with 1a with the aim to assess the relative propensity of nitrile and alkyne groups in the reaction. The triple bond reacted in the transannulation about two times faster
  • than the nitrile group and again the 3,4-disubstituted pyrrole 4 regioisomer dominated over the 2,4-disubstitued pyrrole 4’ (Scheme 4). To demonstrate the compatibility of the formed N-perfluoroalkylpyrroles with the conditions of pyrrole derivatization by metalation in position two and reaction with
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Published 18 Feb 2021

Coupling biocatalysis with high-energy flow reactions for the synthesis of carbamates and β-amino acid derivatives

  • Alexander Leslie,
  • Thomas S. Moody,
  • Megan Smyth,
  • Scott Wharry and
  • Marcus Baumann

Beilstein J. Org. Chem. 2021, 17, 379–384, doi:10.3762/bjoc.17.33

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  • furthermore allowed the ester/nitrile moieties to be unaffected. Indeed, it was established subsequently that alkaline hydrolysis of the ester group requires a prolonged reaction time at an elevated temperature (Scheme 6). Importantly this can be achieved selectively without a concomitant cleavage of the
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Published 04 Feb 2021

Synthesis of legonmycins A and B, C(7a)-hydroxylated bacterial pyrrolizidines

  • Wilfred J. M. Lewis,
  • David M. Shaw and
  • Jeremy Robertson

Beilstein J. Org. Chem. 2021, 17, 334–342, doi:10.3762/bjoc.17.31

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  • of further C(7a)-hydroxylated bacterial pyrrolizidines and related molecules. Pyrrolizidine 14 (Scheme 1), the key intermediate in Snider’s improved route to jenamidine A and Bode’s preparation of pyrrolizixenamides A (9) and D (12), is formed by N-cyclization onto the nitrile group in cyano-β
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Published 02 Feb 2021

The preparation and properties of 1,1-difluorocyclopropane derivatives

  • Kymbat S. Adekenova,
  • Peter B. Wyatt and
  • Sergazy M. Adekenov

Beilstein J. Org. Chem. 2021, 17, 245–272, doi:10.3762/bjoc.17.25

Graphical Abstract
  • nitrile 63 could be obtained by the reaction of phenylacetonitrile (61) with 1,2-dibromo-1,1-difluoroethane (62) using sodium amide as the base (Scheme 27) [69]. However, the yield of this reaction was only 10%. The gem-difluorocyclopropanes 65 were synthesized from the reaction of gem-difluoroolefins 64
  • nitrile hydratase–amidase-containing biocatalytic system and showed a high chemo-, regio-, and enantioselectivity in the hydrolysis of nitriles and dinitriles. The biocatalytic transformations of nitrile 81 (Scheme 33) supplied an effective route to optically active 2,2-difluorosubstituted 3
  • by the two attached fluorine atoms. The nucleophilic attack of the nitrile, followed by cyclization and aromatization could then give the pyrrole derivatives 142. Later, Xiao et al. performed another ring-opening reaction of gem-difluorocyclopropyl ketones 143, this time mediated by BX3 (X = F, Cl
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Published 26 Jan 2021

All-carbon [3 + 2] cycloaddition in natural product synthesis

  • Zhuo Wang and
  • Junyang Liu

Beilstein J. Org. Chem. 2020, 16, 3015–3031, doi:10.3762/bjoc.16.251

Graphical Abstract
  • underwent successive intramolecular Michael addition and hydrolytic nitrile reduction to give 79 in 46% yield in two steps. Extensive studies of the nitrile reduction eventually identified that Et3Al and DIBAL-H could effectively reduce the nitrile group to the corresponding aldehyde and treatment with
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Published 09 Dec 2020

Naphthalonitriles featuring efficient emission in solution and in the solid state

  • Sidharth Thulaseedharan Nair Sailaja,
  • Iván Maisuls,
  • Jutta Kösters,
  • Alexander Hepp,
  • Andreas Faust,
  • Jens Voskuhl and
  • Cristian A. Strassert

Beilstein J. Org. Chem. 2020, 16, 2960–2970, doi:10.3762/bjoc.16.246

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  • considerations: (1) the p-phenyl substituents act as electron-donor units and as AIE activators; (2) the nitrile groups provide a significant π-acceptor strength, and also promote hydrogen bonding in the aggregates [39][40][41][42]. By varying the substituents at the phenyl groups ranging from mild π-donors
  • some intermolecular CH…π interactions between the C–H units of the residual tolyl group and the central ring of the naphthalonitrile bearing two nitrile groups with a CH/π-ring distance of 2.780 Å (Figure 2A). Even though the naphthalonitrile planes of two adjacent head-to-tail-arranged molecules are
  • together by C–H…N intermolecular hydrogen bonds with distances of 3.006 Å for C–H(2e)/N(6) and 3.083 Å for C–H(2d)/N(6) while involving hydrogen atoms of the tolyl moieties and the nitrogen atoms of nitrile groups. Then, these dimeric substructures are linked by C–H…N intermolecular interactions to
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Published 02 Dec 2020

Ultrasound-assisted Strecker synthesis of novel 2-(hetero)aryl-2-(arylamino)acetonitrile derivatives

  • Emese Gal,
  • Luiza Gaina,
  • Hermina Petkes,
  • Alexandra Pop,
  • Castelia Cristea,
  • Gabriel Barta,
  • Dan Cristian Vodnar and
  • Luminiţa Silaghi-Dumitrescu

Beilstein J. Org. Chem. 2020, 16, 2929–2936, doi:10.3762/bjoc.16.242

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  • -nitrile pharmacophoric units. In this work we report the experimental procedure for the ultrasound-assisted addition of the TMSCN nucleophile to heterocyclic aldimines. The substrates tested were mostly represented by a series of phenothiazinyl aldimines, but the scope of the new synthetic procedure was
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Published 30 Nov 2020

Synthesis of 4-substituted azopyridine-functionalized Ni(II)-porphyrins as molecular spin switches

  • Jannis Ludwig,
  • Tobias Moje,
  • Fynn Röhricht and
  • Rainer Herges

Beilstein J. Org. Chem. 2020, 16, 2589–2597, doi:10.3762/bjoc.16.210

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  • shown that the spin switching efficiency is strongly dependent on the solvent and on the substituent at the 4-position of the pyridine unit. We now introduced thiol, disulfide, thioethers, nitrile and carboxylic acid groups and investigated their spin switching efficiency. Keywords: azopyridines; Ni(II
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Published 21 Oct 2020

Thermodynamic and electrochemical study of tailor-made crown ethers for redox-switchable (pseudo)rotaxanes

  • Henrik Hupatz,
  • Marius Gaedke,
  • Hendrik V. Schröder,
  • Julia Beerhues,
  • Arto Valkonen,
  • Fabian Klautzsch,
  • Sebastian Müller,
  • Felix Witte,
  • Kari Rissanen,
  • Biprajit Sarkar and
  • Christoph A. Schalley

Beilstein J. Org. Chem. 2020, 16, 2576–2588, doi:10.3762/bjoc.16.209

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  • the optoelectronic properties of the NDI unit. The binding properties suggest that the combination of the A1·BArF24 axle and NDIC8 is optimal for the synthesis of an NDI-containing [2]rotaxane. We applied Takata’s catalyst-free stoppering approach [58] using the nitrile oxide St for the preparation of
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Published 20 Oct 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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  • enolisable ketone 293 is used, enolate complex 294 can be formed in the presence of base (Scheme 49a) [116]. The complex in this example is then proposed to proceed via an oxidative quenching cycle with bromo nitrile 295 to form α-cyano radicals 295• that then add to another molecule of 294
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Published 29 Sep 2020

Recent synthesis of thietanes

  • Jiaxi Xu

Beilstein J. Org. Chem. 2020, 16, 1357–1410, doi:10.3762/bjoc.16.116

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Published 22 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

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  • corresponding to the free iminoxyl radical, which indicates the reversibility of dimerization [53]. During the oxidation of pivalic aldoxime 1e by Ag2O, the formation of nitrile oxide 6e was observed, which then slowly dimerized to the corresponding furoxan 7e. The kinetics of the decomposition of dialkyl
  • ruthenium catalyst. This possible reaction pathway was confirmed by a control experiment in which the hydroxyiminomethylisoxazoline was transformed to a nitrile in the presence of [RuCl2(p-cymene)]2. Aromatic oximes with various substituents, as well as heteroaromatic oximes, give cyano-substituted
  • oximes (products 147e,f) were successfully used. Oxidative cyclization of unsaturated oximes with the formation of isoxazolines or cyclic nitrones and the introduction of a nitrile group was achieved using the CuCN/N,N,N′,N′′,N′′-pentamethyldiethyltriamine (PMDETA)/TBHP system (Scheme 50) [139]. Other
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Published 05 Jun 2020

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

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  • 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
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