Tandem diazotization/cyclization approach for the synthesis of a fused 1,2,3-triazinone-furazan/furoxan heterocyclic system

• Yuri A. Sidunets,
• Valeriya G. Melekhina and
• Leonid L. Fershtat

Beilstein J. Org. Chem. 2024, 20, 2342–2348, doi:10.3762/bjoc.20.200

• extended this approach to amides 5 containing a furazan ring that were obtained via the reaction of readily available 4-amino-3-furazancarboxylic acid 6 with various amines using 2-(1H-benzotriazole-1-yl)-1,1,3,3-tetramethylaminium tetrafluoroborate (TBTU) as a coupling reagent (Scheme 3; see Supporting

The Groebke–Blackburn–Bienaymé reaction in its maturity: innovation and improvements since its 21st birthday (2019–2023)

• Cristina Martini,
• Muhammad Idham Darussalam Mardjan and
• Andrea Basso

Beilstein J. Org. Chem. 2024, 20, 1839–1879, doi:10.3762/bjoc.20.162

• combination of reactants was studied, but a major hurdle was found to be the imine formation step in aqueous media. Consequently, imines were first prepared as metastable adducts (with benzotriazole or p-TSA as stabilizers) and then tested with isocyanides in the presence of the template protein, involving

Three-component N-alkenylation of azoles with alkynes and iodine(III) electrophile: synthesis of multisubstituted N-vinylazoles

• Jun Kikuchi,
• Roi Nakajima and
• Naohiko Yoshikai

Beilstein J. Org. Chem. 2024, 20, 891–897, doi:10.3762/bjoc.20.79

• between various azoles and internal alkynes is mediated by benziodoxole triflate as the electrophile in a trans-fashion, affording azole-bearing vinylbenziodoxoles in moderate to good yields. The tolerable azole nuclei include pyrazole, indazole, 1,2,3-triazole, benzotriazole, and tetrazole. The iodanyl

• reaction of azoles with alkynes and iodine(III) electrophile, benziodoxole triflate (BXT, 1; Scheme 1c). Displaying exclusive trans-selectivity, the reaction tolerates a broad range of azoles, including pyrazole, 1,2,3-triazole, tetrazole, indazole, and benzotriazole, with internal alkynes as coupling

• yield in a ratio of 7:3. Indazole and its 4-bromo and 6-methoxycarbonyl analogues afforded the expected N1-alkenylated products 4ea–4ga in 43–68% yields. 1,2,3-Triazole and benzotriazole both smoothly participated in the reaction to give their respective products 4ha and 4ia in 60% and 81% yields

N-Boc-α-diazo glutarimide as efficient reagent for assembling N-heterocycle-glutarimide diads via Rh(II)-catalyzed N–H insertion reaction

• Grigory Kantin,
• Pavel Golubev,
• Alexander Sapegin,
• Alexander Bunev and
• Dmitry Dar’in

Beilstein J. Org. Chem. 2023, 19, 1841–1848, doi:10.3762/bjoc.19.136

• with a diazo reagent under neutral conditions may give rise to a separate regioisomer which is different from the product obtained by reaction with an alkyl halide under basic conditions. Recently, we designed a thalidomide analogue 1a in which the phthalimide moiety was replaced with benzotriazole

• also highly regioselective, proceeding via attack on the 2-N atom to give products 6m–o. In the instance of unsubstituted benzotriazole, a minor regioisomer 6m' was identified with a calculated yield of 6% using NMR data. Benzotriazoles featuring electron-withdrawing substituents showed incomplete

• , resulting in glutarimides with a heterocyclic fragment at the α-position 1a–e – structures in demand for the design of CRBN ligands and immunomodulatory drugs. In compound 6n, catalytic hydrogenation was used to reduce the nitro group, resulting in the production of a benzotriazole analog of pomalidomide

Quinoxaline derivatives as attractive electron-transporting materials

• Zeeshan Abid,
• Liaqat Ali,
• Sughra Gulzar,
• Faiza Wahad,
• Raja Shahid Ashraf and
• Christian B. Nielsen

Beilstein J. Org. Chem. 2023, 19, 1694–1712, doi:10.3762/bjoc.19.124

• was used to prove that employing the same acceptor unit for both donor and acceptor is an effective approach. This strategy has been shown to be successful in achieving high Voc for benzotriazole materials, and now it has been extended to quinoxaline materials [38]. Ji et al. introduced fluorine atoms

• study raises a concern regarding the performance of dyes with tert-butyl substituted DPQ acceptors, either containing benzene (Qx74) or thiophene (Qx75) as a π-conjugation linker and their benzotriazole analogue. While the incorporation of the Qx enhances the interaction between the donor and acceptor

Chemistry of polyhalogenated nitrobutadienes, 17: Efficient synthesis of persubstituted chloroquinolinyl-1H-pyrazoles and evaluation of their antimalarial, anti-SARS-CoV-2, antibacterial, and cytotoxic activities

• Viktor A. Zapol’skii,
• Isabell Berneburg,
• Ursula Bilitewski,
• Melissa Dillenberger,
• Katja Becker,
• Stefan Jungwirth,
• Aditya Shekhar,
• Bastian Krueger and
• Dieter E. Kaufmann

Beilstein J. Org. Chem. 2022, 18, 524–532, doi:10.3762/bjoc.18.54

• Plasmodium has been developed and is reported in the literature [24]. Results and Discussion The vinylic SN reaction of 2-nitroperchlorobutadiene (1) with four equivalents of the azoles such as 1H-pyrazole, 1H-1,2,4-triazole, or 1H-benzotriazole affords similarly to [25] the corresponding 1,1

Synthesis and physicochemical evaluation of fluorinated lipopeptide precursors of ligands for microbubble targeting

• Masayori Hagimori,
• Estefanía E. Mendoza-Ortega and
• Marie Pierre Krafft

Beilstein J. Org. Chem. 2021, 17, 511–518, doi:10.3762/bjoc.17.45

• fluorine–fluorine interactions. Experimental Materials. We purchased Fmoc-protected amino acids, N,N-dimethylformamide (DMF), dichloromethane (DCM), methanol, 1-hydroxybenzotriazole (HOBT), 2-(1H-benzotriazole-1-yl)-1,1,3,3-tetramethyluronium hexafluorophosphate (HBTU), N,N-diisopropylethylamine (DIPEA

p-Pyridinyl oxime carbamates: synthesis, DNA binding, DNA photocleaving activity and theoretical photodegradation studies

• Panagiotis S. Gritzapis,
• Panayiotis C. Varras,
• Nikolaos-Panagiotis Andreou,
• Katerina R. Katsani,
• Konstantinos Dafnopoulos,
• George Psomas,
• Zisis V. Peitsinis,
• Alexandros E. Koumbis and
• Konstantina C. Fylaktakidou

Beilstein J. Org. Chem. 2020, 16, 337–350, doi:10.3762/bjoc.16.33

• . Reports involve arylaminyl radicals (ArNH∙) formed from arylhydrazones through the photoinduced cleavage of N–N single bonds (along with an iminyl radical) [48] or from benzotriazole derivatives after also a N–N single bond cleavage and nitrogen elimination [36]. It has been reported that amine-centred

Recent advances in transition-metal-catalyzed incorporation of fluorine-containing groups

• Xiaowei Li,
• Xiaolin Shi,
• Xiangqian Li and
• Dayong Shi

Beilstein J. Org. Chem. 2019, 15, 2213–2270, doi:10.3762/bjoc.15.218

Synthesis of unnatural α-amino esters using ethyl nitroacetate and condensation or cycloaddition reactions

• Glwadys Gagnot,
• Vincent Hervin,
• Eloi P. Coutant,
• Sarah Desmons,
• Racha Baatallah,
• Victor Monnot and
• Yves L. Janin

Beilstein J. Org. Chem. 2018, 14, 2846–2852, doi:10.3762/bjoc.14.263

• function of 16, followed by its coupling with glycine or phenylalanine ethyl esters (respectively 20a and 20b) using 2-(1H-benzotriazole-1-yl)-1,1,3,3-tetramethylaminium tetrafluoroborate (TBTU) as a coupling agent to give the corresponding amides 21a,b. The isoxazole ring of these compounds was then

Anomeric modification of carbohydrates using the Mitsunobu reaction

• Julia Hain,
• Patrick Rollin,
• Werner Klaffke and
• Thisbe K. Lindhorst

Beilstein J. Org. Chem. 2018, 14, 1619–1636, doi:10.3762/bjoc.14.138

• glycosylation, Grochowski explored the synthesis of new nucleoside analogues. 1-Hydroxy-benzotriazole, 1-hydroxy-2-cyanobenzimidazole, 1-hydroxyuracil, and 1-hydroxythymine were used to prepare the respective NO-furanosides in the manno- and ribo-series [115][116][117]. Miscellaneous The Mitsunobu reaction was

Hypervalent organoiodine compounds: from reagents to valuable building blocks in synthesis

• Gwendal Grelier,
• Benjamin Darses and
• Philippe Dauban

Beilstein J. Org. Chem. 2018, 14, 1508–1528, doi:10.3762/bjoc.14.128

• high yielding N-arylation of 1H-1,2,3-benzotriazole (BTA), utilizing symmetrical diaryl-λ3-iodanes as two-fold aryl donors has been reported in the presence of Pd(OAc)2 and TPPTS as a water-soluble ligand, and copper(II) phenylcyclopropylcarboxylate (Scheme 35) [74]. Noteworthy, it is mentioned that Ar

• -dimethylpyrazole. The reaction has been extended to 1,2,3-triazoles, benzotriazole, and pyrazole. In the latter case, the use of (styryl)(aryl)-λ3-iodanes has also proved to be possible, with the styryl moiety being selectively transferred in the first step. The following step of C–H activation then gives access

• dibenzosulfides and dibenzoselenides from cyclic diaryl-λ3-iodanes. Synthesis of dibenzosulfones from cyclic diaryl-λ3-iodanes. Seminal study with linear diaryl-λ3-iodanes. N-Arylation of benzotriazole with symmetrical diaryl-λ3-iodanes. Tandem catalytic C–H/N–H arylation of indoles with diaryl-λ3-iodanes. Tandem

Recent applications of click chemistry for the functionalization of gold nanoparticles and their conversion to glyco-gold nanoparticles

• Vivek Poonthiyil,
• Thisbe K. Lindhorst,
• Vladimir B. Golovko and
• Antony J. Fairbanks

Beilstein J. Org. Chem. 2018, 14, 11–24, doi:10.3762/bjoc.14.2

• derivatives, DCM, 11000 atm, 25 °C, 15–24 h [48]. The synthesis of AuNPs functionalized with strained alkyne derivatives. HBTU = O-benzotriazole-N,N,N',N'-tetramethyluroniumhexafluorophosphate; DIPEA = N,N-diisopropylethylamine [57]. A schematic representation of the SPAAC between azide-functionalized

Mechanochemical synthesis of thioureas, ureas and guanidines

• Vjekoslav Štrukil

Beilstein J. Org. Chem. 2017, 13, 1828–1849, doi:10.3762/bjoc.13.178

• 27, it has been explicitly stated in the literature that these compounds are very reactive intermediates and immediately decompose to isothiocyanates and 1H-benzotriazole (HBt). With this in mind, we investigated the possibility to run the thiocarbamoylation reaction of para-substituted anilines as

• , confirmed that mechanochemistry afforded the elusive aromatic N-thiocarbamoyl benzotriazoles 27 in quantitative yields after only 10 minutes of LAG and a simple aqueous work-up. Furthermore, conducting the reaction in two steps, where the thiocarbamoyl benzotriazole was prepared in the first step followed

• by the addition of the second equivalent of aniline, led to non-symmetrical thioureas 28e–g in ≥97% yields (Scheme 9). Treating p-pda with two equivalents of 26 gave 99% of bis-thiocarbamoyl benzotriazole 29, a masked 1,4-phenylene diisothiocyanate equivalent. In contrast, the analogous reaction of o

Isoxazole derivatives as new nitric oxide elicitors in plants

• Anca Oancea,
• Emilian Georgescu,
• Florentina Georgescu,
• Alina Nicolescu,
• Elena Iulia Oprita,
• Catalina Tudora,
• Lucian Vladulescu,
• Marius-Constantin Vladulescu,
• Florin Oancea and
• Calin Deleanu

Beilstein J. Org. Chem. 2017, 13, 659–664, doi:10.3762/bjoc.13.65

• diacetate), a non-fluorescent compound, which reacts with NO to form a fluorescent benzotriazole and does not react with any ROS [64][65][66][67]. Fluorescence microscopy images of all 3,5-disubstituted isoxazoles-treated Arabidopsis leaves showed a pronounced presence of ROS at both concentrations of

A chemoselective and continuous synthesis of m-sulfamoylbenzamide analogues

• Arno Verlee,
• Thomas Heugebaert,
• Tom van der Meer,
• Pavel I. Kerchev,
• Frank Van Breusegem and
• Christian V. Stevens

Beilstein J. Org. Chem. 2017, 13, 303–312, doi:10.3762/bjoc.13.33

• dichloromethane was used as solvent. The coupling of carboxylic acids with amines in flow through a benzotriazole activation [19], or with immobilized reagents as for the synthesis of grossamide [20] is already known. However, we wanted to use m-(chlorosulfonyl)benzoyl chloride since this can be synthesized in

Inhibition of peptide aggregation by means of enzymatic phosphorylation

• Kristin Folmert,
• Malgorzata Broncel,
• Hans v. Berlepsch,
• Christopher H. Ullrich,
• Mary-Ann Siegert and
• Beate Koksch

Beilstein J. Org. Chem. 2016, 12, 2462–2470, doi:10.3762/bjoc.12.240

• according to standard Fmoc chemistry using preloaded Fmoc-Leu-NovaSyn®TGA resin (0.3 mmol g−1, Novabiochem). Standard couplings were performed in DMF with Fmoc-amino acids and TBTU (O-(benzotriazole-1-yl)-N,N,N’,N’-tetramethyluronium tetrafluoroborate)/HOBt (1-hydroxybenzotriazole)/DIC (N,N

Synthesis and characterization of benzodithiophene and benzotriazole-based polymers for photovoltaic applications

• Desta Gedefaw,
• Marta Tessarolo,
• Margherita Bolognesi,
• Mario Prosa,
• Renee Kroon,
• Wenliu Zhuang,
• Patrik Henriksson,
• Kim Bini,
• Ergang Wang,
• Michele Muccini,
• Mirko Seri and
• Mats R. Andersson

Beilstein J. Org. Chem. 2016, 12, 1629–1637, doi:10.3762/bjoc.12.160

• National Research Council (CNR) − Institute of Organic Synthesis and Photoreactivity (ISOF), Via P. Gobetti, 101, 40129 Bologna, Italy 10.3762/bjoc.12.160 Abstract Two high bandgap benzodithiophene–benzotriazole-based polymers were synthesized via palladium-catalysed Stille coupling reaction. In order to

• compare the effect of the side chains on the opto-electronic and photovoltaic properties of the resulting polymers, the benzodithiophene monomers were substituted with either octylthienyl (PTzBDT-1) or dihexylthienyl (PTzBDT-2) as side groups, while the benzotriazole unit was maintained unaltered. The

• ; fluorinated benzotriazole; Introduction Over the past decades the research on bulk heterojunction (BHJ) polymer solar cells (PSCs) has been intensified due to the attractive perspectives of producing lightweight and flexible devices via a scalable printing technology at low-cost. The active layer consists of

Conjugate addition–enantioselective protonation reactions

• James P. Phelan and
• Jonathan A. Ellman

Beilstein J. Org. Chem. 2016, 12, 1203–1228, doi:10.3762/bjoc.12.116

• reaction, Lou and Cheng explored the addition of various nitrogen [54], sulfur [55], and carbon nucleophiles [56][57] to α-branched vinyl ketones (Scheme 29). The nitrogen heterocycles benzotriazole (126a), triazole (126b), and 5-phenyltriazole (126c), all reacted smoothly with vinyl ketone 118. To achieve

Synthesis of highly functionalized 2,2'-bipyridines by cyclocondensation of β-ketoenamides – scope and limitations

• Paul Hommes and
• Hans-Ulrich Reissig

Beilstein J. Org. Chem. 2016, 12, 1170–1177, doi:10.3762/bjoc.12.112

• in 42% yield. The corresponding β-ketoenamides containing pyridine moieties at the acylated nitrogen were prepared by standard methods with the respective acid chlorides that furnished compounds 3c and 3d in good yields. For the synthesis of compound 3e it was advantageous to employ the benzotriazole

Copper-catalyzed aminooxygenation of styrenes with N-fluorobenzenesulfonimide and N-hydroxyphthalimide derivatives

• Yan Li,
• Xue Zhou,
• Guangfan Zheng and
• Qian Zhang

Beilstein J. Org. Chem. 2015, 11, 2721–2726, doi:10.3762/bjoc.11.293

• aminooxygenation reaction of alkenes with phthalimide and (diacetoxyiodo)benzene through cis-aminopalladation and SN2 C–O bond formation [34]. In 2013, Zhu and co-workers described an n-Bu4NI-catalyzed aminooxygenation of inactive alkenes with benzotriazole and water which underwent a nitrogen-centred radical

Probing multivalency in ligand–receptor-mediated adhesion of soft, biomimetic interfaces

• Stephan Schmidt,
• Hanqing Wang,
• Daniel Pussak,
• Simone Mosca and
• Laura Hartmann

Beilstein J. Org. Chem. 2015, 11, 720–729, doi:10.3762/bjoc.11.82

• maximize receptor adhesion and selectivity. Experimental Materials Benzophenone was purchased from Acros Organics, benzotriazole-1-yloxytripyrrolidinophosphonium hexafluorophosphate (PyBOP) and 1-hydroxybenzotriazole (HOBt) from IRIS. All other chemicals were purchased from Sigma-Aldrich. General procedure

Diastereoselective and enantioselective conjugate addition reactions utilizing α,β-unsaturated amides and lactams

• Katherine M. Byrd

Beilstein J. Org. Chem. 2015, 11, 530–562, doi:10.3762/bjoc.11.60

• studies as the basis for the development of the 1,4-addition of N-heterocycles to α,β-unsaturated imides. They applied both substituted and unsubstituted purines, benzotriazole, and 5-substituted tetrazoles as nucleophiles to this reaction, which resulted in moderate to excellent yields and excellent

Come-back of phenanthridine and phenanthridinium derivatives in the 21st century

• Lidija-Marija Tumir,
• Marijana Radić Stojković and
• Ivo Piantanida

Beilstein J. Org. Chem. 2014, 10, 2930–2954, doi:10.3762/bjoc.10.312

• (Scheme 1) [9], Bischler–Napieralski reactions [10], reduction of phenanthridones [11][12], free radical methodology, palladium/rhodium/iron-catalysed reactions, etc. One of the approaches to the large variety of 6-arylphenanthridine derivatives was the synthesis starting from benzotriazole derivatives of

• diarylmethanes, acridine, xanthene, thioxanthene, etc. It was based on the generation of a benzotriazole-stabilized carbanion followed by oxidation of this carbanion by copper iodide to form a radical. Subsequent elimination of nitrogen followed by ring closure yielded phenanthridine (Scheme 2) [13][14]. In the

• ][21][22][23][24] and the synthesis based on transition metal-catalysis [15][27][28][29][30][31][32][33][34][35][36][37]. The main advantage of the radical-based phenanthridine synthesis is easy available and generally cheap starting material (benzotriazole, aminobiphenyl, arylaldehyde, N-(ortho

Facile synthesis of 1-alkoxy-1H-benzo- and 7-azabenzotriazoles from peptide coupling agents, mechanistic studies, and synthetic applications

• Mahesh K. Lakshman,
• Manish K. Singh,
• Mukesh Kumar,
• Raghu Ram Chamala,
• Vijayender R. Yedulla,
• Domenick Wagner,
• Evan Leung,
• Lijia Yang,
• Asha Matin and
• Sadia Ahmad

Beilstein J. Org. Chem. 2014, 10, 1919–1932, doi:10.3762/bjoc.10.200

• ][1,2,3]triazole, via in situ formation of pyrrolidine enamines and Pd catalysis. Keywords: alkoxy; azabenzotriazole; benzotriazole; peptide-coupling; phosphonium; Introduction Benzotriazole derivatives are of importance in diverse contexts. As examples, in medicinal chemistry substituted benzotriazoles

• properties, particularly against the human pathogen Acanthamoeba that can infect a variety of organs such as brain, eyes, skin, and lungs [4]. Triazole and benzotriazole derivatives have been evaluated as antitumor agents, with several showing high activities [5], and a benzotriazole derivative was shown to

• inhibit proliferation of hepatocarcinoma [6]. Several N-alkylbenzotriazoles show potent antimicrobial action [7] and others have been evaluated as aromatase inhibitors [8]. Benzotriazole derivatives have also been reported to be inhibitors of MAP kinases [9]. Although esters of BtOH are generally