Attempted synthesis of a meta-metalated calix[4]arene

• Christopher D. Jurisch and
• Gareth E. Arnott

Beilstein J. Org. Chem. 2019, 15, 1996–2002, doi:10.3762/bjoc.15.195

• yielding transformations to azide and 1,2,3-triazole derivatives which may have application in other areas of research. Keywords: calixarene; inherent chirality; mesoionic carbene; mononitration; ruthenacycle; Introduction Calix[4]arenes are a class of diverse macrocyclic compounds which have been the

• Ullmann-type coupling to give aryl azide 2, which readily reacted with phenylacetylene in a copper-catalyzed Huisgen 1,3-dipolar cycloaddition to give 1,2,3-triazole 3 (Scheme 1). The formation of the ruthenacycle was then achieved using Albrecht’s method involving regioselective methylation of triazole 3

Polyaminoazide mixtures for the synthesis of pH-responsive calixarene nanosponges

• Antonella Di Vincenzo,
• Antonio Palumbo Piccionello,
• Alberto Spinella,
• Delia Chillura Martino,
• Marco Russo and
• Paolo Lo Meo

Beilstein J. Org. Chem. 2019, 15, 633–641, doi:10.3762/bjoc.15.59

• azide stretching of the reticulating agent, respectively. On the other hand, a tiny signal at 3140 cm−1 appears, which can be attributed to the Csp2–H stretching typical of the newly formed 1,2,3-triazole ring. The occurrence of the triazole ring is also accounted for by tiny signals at 1244, 1204, 1050

Copper(I)-catalyzed tandem reaction: synthesis of 1,4-disubstituted 1,2,3-triazoles from alkyl diacyl peroxides, azidotrimethylsilane, and alkynes

• Muhammad Israr,
• Changqing Ye,
• Munira Taj Muhammad,
• Yajun Li and
• Hongli Bao

Beilstein J. Org. Chem. 2018, 14, 2916–2922, doi:10.3762/bjoc.14.270

• available lauroyl peroxide (2a), and TMSN3 (Table 1). In a preliminary experiment, the reaction of 1a with 2a in the presence of 10 mol % of CuCl in THF at 50 °C afforded 1,4-disubstituted 1,2,3-triazole 3a in 65% isolated yield (Table 1, entry 1). Surprisingly, under these conditions no CuAAC product

Assembly of fully substituted triazolochromenes via a novel multicomponent reaction or mechanochemical synthesis

• Robby Vroemans,
• Yenthel Verhaegen,
• My Tran Thi Dieu and
• Wim Dehaen

Beilstein J. Org. Chem. 2018, 14, 2689–2697, doi:10.3762/bjoc.14.246

• , which enables them to undergo a high variety of reactions and functionalizations [15]. Combining the chromene core with the 1,2,3-triazole structural motif has led to some interesting new molecules [16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31]. Very recently, spiro-fused

• ], via intramolecular cyclization of a diazomethane group and a nitrile [23], or via our recently reported NH-triazole synthesis starting from 6-methoxyflavanone [24]. Furthermore, 1,4,5-trisubstituted 1,2,3-triazole annulated chromenes have been reported via an intramolecular arylation reaction of 1,2,3

• substituents on the chromene core and 1,2,3-triazole offer a lot of possibilities for further derivatization and optimization towards biologically relevant structures such as flavonoid structures. Our group developed a Knoevenagel-assisted three-component reaction of (protected) salicylaldehyde, ethyl

Catalyst-free synthesis of 4-acyl-NH-1,2,3-triazoles by water-mediated cycloaddition reactions of enaminones and tosyl azide

• Lu Yang,
• Yuwei Wu,
• Yiming Yang,
• Chengping Wen and
• Jie-Ping Wan

Beilstein J. Org. Chem. 2018, 14, 2348–2353, doi:10.3762/bjoc.14.210

• , authentically mild conditions (40 °C stirring) as well as practical scalability. Keywords: additive-free; catalyst-free; cycloaddition; enaminones; on water; 1,2,3-triazole; Introduction Discovering sustainable chemical syntheses constitutes one central issue of modern organic chemistry. A large number of

• , including those reactions involving valuable C–C [7][8][9][10][11], C–heteroatom [12][13][14][15][16], heteroatom–heteroatom [17][18] bond formation as well as divergent cascade reactions [19][20][21][22][23], are presently taking place to guide the progress of sustainable organic synthesis. 1,2,3-Triazole

• development of these metal-catalyzed cycloaddition strategies [33][34][35]. Alongside the vast progress happened in MAAC-based 1,2,3-triazole synthesis, the past decade has witnessed the emergence of another powerful cycloaddition tool for the 1,2,3-triazole synthesis: the metal-free cycloaddition of azides

Revisiting ring-degenerate rearrangements of 1-substituted-4-imino-1,2,3-triazoles

• James T. Fletcher,
• Matthew D. Hanson,
• Joseph A. Christensen and
• Eric M. Villa

Beilstein J. Org. Chem. 2018, 14, 2098–2105, doi:10.3762/bjoc.14.184

• James T. Fletcher Matthew D. Hanson Joseph A. Christensen Eric M. Villa Department of Chemistry, Creighton University, 2500 California Plaza, Omaha, NE 68178, U.S.A. 10.3762/bjoc.14.184 Abstract The 1-substituted-4-imino-1,2,3-triazole motif is an established component of coordination compounds

• four imine products via a dynamic equilibrium of condensation, rearrangement and hydrolysis steps. Kinetic studies utilizing 1-(4-nitrophenyl)-1H-1,2,3-triazole-4-carbaldehyde with varying amines showed rearrangement rates sensitive to both steric and electronic factors. Such measurements were

• facilitated by a high throughput colorimetric assay to directly monitor the generation of a 4-nitroaniline byproduct. Keywords: colorimetric assay; condensation; imine exchange; rearrangement; 1,2,3-triazole; Introduction Examples of multidentate chelators comprised of 1,2,3-triazole units have surged in

Synthesis and supramolecular self-assembly of glutamic acid-based squaramides

• Juan V. Alegre-Requena,
• Marleen Häring,
• Isaac G. Sonsona,
• Alex Abramov,
• Eugenia Marqués-López,
• Raquel P. Herrera and
• David Díaz Díaz

Beilstein J. Org. Chem. 2018, 14, 2065–2073, doi:10.3762/bjoc.14.180

• properties of supramolecular gels [33]. Specifically, we exchanged the amide group of N-stearoyl-L-glutamic acid (1, Figure 1), a known LMW gelator [34], by its non-classical isostere [35][36] 1,4-disubstituted 1,2,3-triazole 2 (Figure 1). This approach enabled us to fine-tuning the gelation capacity and the

Hyper-reticulated calixarene polymers: a new example of entirely synthetic nanosponge materials

• Alberto Spinella,
• Marco Russo,
• Antonella Di Vincenzo,
• Delia Chillura Martino and
• Paolo Lo Meo

Beilstein J. Org. Chem. 2018, 14, 1498–1507, doi:10.3762/bjoc.14.127

• ]) between a heptakis(6-azido-6-deoxy)-β-cyclodextrin and a tetrakis(propargyloxy)calix[4]arene [11][31][32]. In this way, a random disposition of the co-monomer units linked by 1,2,3-triazole units is achieved. The obtained CyCaNSs benefit from several advantages. First, the properties of the material can

• ), in which the host monomers are joined by means of bis(1,2,3-triazole) subunits having different features. More in detail, four different nanosponges CaNS1-CaNS4 were obtained by reacting the 5,11,17,23-tetra-tert-butyl-25,26,27,28-tetrakis(propargyloxy)calix[4]arene (Ca-OP, Scheme 1a) with four

• , indeed, possible dependence on pH might arise from the presence of the weakly basic 1,2,3-triazole rings of the linker units, which can supply an overall positive charge density to the polymer lattice upon protonation. A first set of experiments was devoted to p-nitroaniline derivatives 1–5. These

Carbohydrate inhibitors of cholera toxin

• Vajinder Kumar and
• W. Bruce Turnbull

Beilstein J. Org. Chem. 2018, 14, 484–498, doi:10.3762/bjoc.14.34

• chelating mechanism. Hughes and co-workers synthesised and evaluated bivalent 1,2,3 triazole-linked galactopyranosides 14 and 15 as shown in Figure 7 [48]. They used a piperazine core as central divalent core on to which the galactose units were attached via flexible linkers. They found that these compounds

Recent progress in the racemic and enantioselective synthesis of monofluoroalkene-based dipeptide isosteres

• Myriam Drouin and
• Jean-François Paquin

Beilstein J. Org. Chem. 2017, 13, 2637–2658, doi:10.3762/bjoc.13.262

• reacted easily in a SN2 reaction to give a more functionalized molecule. For example, treatment of the chlorinated monofluoroalkene with NaN3 provided the corresponding N3-containing monofluoroalkene. The azide group underwent a 1,3-dipolar cycloaddition to give a 1,2,3-triazole, which is also a peptide

¹⁵N-Labelling and structure determination of adamantylated azolo-azines in solution

• Sergey L. Deev,
• Alexander S. Paramonov,
• Tatyana S. Shestakova,
• Igor A. Khalymbadzha,
• Oleg N. Chupakhin,
• Julia O. Subbotina,
• Oleg S. Eltsov,
• Pavel A. Slepukhin,
• Vladimir L. Rusinov,
• Alexander S. Arseniev and
• Zakhar O. Shenkarev

Beilstein J. Org. Chem. 2017, 13, 2535–2548, doi:10.3762/bjoc.13.250

• product structure were also found for N-arylation or N-alkylation with tert-butyl fragments in the series of 1,2,3-triazole [15][16], tetrazole [17][18][19][20], and purine [21] derivatives. Meanwhile, knowledge of the accurate chemical structures of N-substituted heterocycles is essential for biomedical

Synthesis, effect of substituents on the regiochemistry and equilibrium studies of tetrazolo[1,5-a]pyrimidine/2-azidopyrimidines

• Elisandra Scapin,
• Paulo R. S. Salbego,
• Caroline R. Bender,
• Alexandre R. Meyer,
• Anderson B. Pagliari,
• Tainára Orlando,
• Geórgia C. Zimmer,
• Clarissa P. Frizzo,
• Helio G. Bonacorso,
• Nilo Zanatta and
• Marcos A. P. Martins

Beilstein J. Org. Chem. 2017, 13, 2396–2407, doi:10.3762/bjoc.13.237

• reactions were planned between phenylacetylene and compounds 6a–c. The 1,2,3-triazole synthesis from the 1,3-dipolar cycloaddition reaction between 6a–c and terminal alkynes catalyzed by copper salts (CuAAC) [41][42][43] confirms that the reaction passes through an azide intermediate. In addition to mild

Solvent-free copper-catalyzed click chemistry for the synthesis of N-heterocyclic hybrids based on quinoline and 1,2,3-triazole

• Martina Tireli,
• Silvija Maračić,
• Stipe Lukin,
• Marina Juribašić Kulcsár,
• Dijana Žilić,
• Mario Cetina,
• Ivan Halasz,
• Silvana Raić-Malić and
• Krunoslav Užarević

Beilstein J. Org. Chem. 2017, 13, 2352–2363, doi:10.3762/bjoc.13.232

• reactions using Cu(II), Cu(I) and Cu(0) catalysts have been successfully implemented to provide novel 6-phenyl-2-(trifluoromethyl)quinolines with a phenyl-1,2,3-triazole moiety at O-4 of the quinoline core. Milling procedures proved to be significantly more efficient than the corresponding solution

• synthesis of 5–8 Based on the recently obtained 1,2,3-triazole-appended N-heterocycles, as promising lead compounds with efficient and selective cytostatic activities [8][9], our research groups share an interest in derivatization of target compounds by a triazole bridge [33]. Quinoline is an important

• containing a trifluoromethyl group at C-2 and a p-halogen-substituted and non-substituted phenyl-1,2,3-triazole moieties. The synthesis of 2-(trifluoromethyl)-6-phenylquinolone was achieved by Conrad–Limpach reaction of a primary aromatic amine with a β-ketoester [37][38]. Namely, thermal condensation of 4

The chemistry and biology of mycolactones

• Matthias Gehringer and
• Karl-Heinz Altmann

Beilstein J. Org. Chem. 2017, 13, 1596–1660, doi:10.3762/bjoc.13.159

An eco-compatible strategy for the diversity-oriented synthesis of macrocycles exploiting carbohydrate-derived building blocks

• Sushil K. Maurya and
• Rohit Rana

Beilstein J. Org. Chem. 2017, 13, 1106–1118, doi:10.3762/bjoc.13.110

• , Himachal Pradesh, 176 061, India 10.3762/bjoc.13.110 Abstract An efficient, eco-compatible diversity-oriented synthesis (DOS) approach for the generation of library of sugar embedded macrocyclic compounds with various ring size containing 1,2,3-triazole has been developed. This concise strategy involves

• attached through Cu-catalyzed azide–alkyne cycloaddition (CuAAC) reaction (couple phase). Noteworthy, herein we utilized the CuAAC reaction as a medium for coupling different building blocks assembled iteratively to generate a 1,2,3-triazole moiety. This 1,2,3-triazole moiety linked as a spacer due to its

Synthesis of ribavirin 2’-Me-C-nucleoside analogues

• Fanny Cosson,
• Aline Faroux,
• Jean-Pierre Baltaze,
• Jonathan Farjon,
• Régis Guillot,
• Jacques Uziel and
• Nadège Lubin-Germain

Beilstein J. Org. Chem. 2017, 13, 755–761, doi:10.3762/bjoc.13.74

• catalytic hydrogenolysis. The latter reaction simultaneously cleaves the benzyl and isopropylidene groups affording compound 2 as a single isomer [22]. In the case of 5-(2’-deoxy-2’-methyl-2’-fluoro-β-D-ribosyl)-1,2,3-triazole-4-carboxamide (3) the synthesis was more delicate as it is necessary to

• procedures for compounds 2, 5–7, and 10–18 are covered by the Ph.D. thesis of Fanny Cosson [22]. 5-(2’-C-Methyl-β-D-ribofuranosyl)-1,2,3-triazole-4-carboxamide (2) [22]: Through the solution of compound 7 (mixture of 7a and 7b, 0.49 g, 1.1 mmol) in anhydrous methanol (14 mL) was bubbled ammonia gas for 2 h

• at 0 °C. Then the mixture was stirred for 12 h at rt and concentrated in vacuum. The residue was purified by flash chromatography (EtOAc/cyclohexane, 3:7 to 1:0) affording the mixture of the corresponding 1-benzyl-4-(2’,3’-O-isopropylidene-2’-C-methyl-β-D-ribofuranosyl)-1,2,3-triazole-5-carboxamide

Ultrasound-promoted organocatalytic enamine–azide [3 + 2] cycloaddition reactions for the synthesis of ((arylselanyl)phenyl-1H-1,2,3-triazol-4-yl)ketones

• Gabriel P. Costa,
• Natália Seus,
• Juliano A. Roehrs,
• Raquel G. Jacob,
• Ricardo F. Schumacher,
• Thiago Barcellos,
• Rafael Luque and
• Diego Alves

Beilstein J. Org. Chem. 2017, 13, 694–702, doi:10.3762/bjoc.13.68

• have been used for this cycloaddition reaction [20][21][22][23][24][25][26][27][28][29]. Organocatalytic approaches based on β-enamine–azide or enolate–azide cycloadditions have been employed to synthesize 1,2,3-triazole scaffolds [30][31][32]. Depending on the organocatalyst employed, different

• -(phenylselanylmethyl)-1,2,3-triazole A (Se-TZ) demonstrated an antidepressant-like effect (Figure 1) [60]. In another example, 5-phenyl-1-(2-(phenylselanyl)phenyl)-1H-1,2,3-triazole-4-carbonitrile B (Se-TZCN) was reported to exhibit antioxidant activities in different in vitro assays (Figure 1) [36]. Selenanyl-quinone

• found to be amenable to a range of 1,3-diketones or aryl azidophenyl selenides, providing an efficient access to novel selenium-containing 1,2,3-triazole compounds in good to excellent yields, in a few minutes of reaction at room temperature. The protocol was extended to activated ketones and

Versatile synthesis of end-reactive polyrotaxanes applicable to fabrication of supramolecular biomaterials

• Atsushi Tamura,
• Asato Tonegawa,
• Yoshinori Arisaka and
• Nobuhiko Yui

Beilstein J. Org. Chem. 2016, 12, 2883–2892, doi:10.3762/bjoc.12.287

• (Scheme 2). After 60 min of reaction, 1H NMR spectra of the obtained products (5a–c) were measured (Figure 3A). In the 1H NMR spectra of 5a and 5b, the protons assignable to 1,2,3-triazole linkages are observed at 8.5 and 9.4 ppm, respectively, which were consistent with the previous report [28]. These

New approaches to organocatalysis based on C–H and C–X bonding for electrophilic substrate activation

• Pavel Nagorny and
• Zhankui Sun

Beilstein J. Org. Chem. 2016, 12, 2834–2848, doi:10.3762/bjoc.12.283

• with halides (Ka ≈ 103–104 M−1 in acetone-d6). Not surprisingly, a higher number of hydrogen bonds with an anion correlated with the higher stability of the receptor/anion complex. 1,2,3-Triazole-based catalysts for the dearomatization of N-heteroarenes The Mancheno group recently explored triazole

• 1,2,3-triazole, ammonium and pyridinium based catalysts. While the asymmetric transformations catalyzed by chiral 1,2,3-triazoles are now well precedented, the feasibility of asymmetric transformations promoted by other types of chiral C–H hydrogen bond donors is yet to be demonstrated. Similarly

• the near future. Electrophile Activation by Hydrogen Bond Donors [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16]. Early examples of C–H hydrogen bonds and their recent use in supramolecular chemistry [18][19][32][33][34]. Design of 1,2,3-triazole-based catalysts for trityl group transfer

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

• -difluoro-2H-benzo[d][1,2,3]triazole (Tz) have attracted much attention and effectively employed in BHJ PSCs due to their intrinsic advantages, potentials and versatility [14][15]. Thanks to the desirable properties such as structural rigidity, planarity, extended π-conjugation length and favorable

• , 0.23 mmol) and 4,7-bis(5-bromothiophen-2-yl)-2-(2-butyloctyl)-5,6-difluoro-2H-benzo[d][1,2,3]triazole (3, 0.15 g, 0.23 mmol) were dissolved in toluene (10 mL) and degassed with N2 gas for 10 minutes. Pd2(dba)3 (4.2 mg, 2 mol %) and P(o-tolyl)3 (6.3 mg, 9 mol %) were added and purged with nitrogen gas

• black solid (149 mg). Synthesis of PTzBDT-2 (4,8-Bis(4,5-dihexylthiophen-2-yl)benzo[1,2-b:4,5-b']dithiophene-2,6-diyl)bis(trimethylstannane) (2, 0.095 g, 0.147 mmol) and 4,7-bis(5-bromothiophen-2-yl)-2-(4-((2-butyloctyl)oxy)butyl)-5,6-difluoro-2H-benzo[d][1,2,3]triazole (3, 0.15 g, 0.147 mmol) were

Beta-hydroxyphosphonate ribonucleoside analogues derived from 4-substituted-1,2,3-triazoles as IMP/GMP mimics: synthesis and biological evaluation

• Tai Nguyen Van,
• Audrey Hospital,
• Corinne Lionne,
• Lars P. Jordheim,
• Charles Dumontet,
• Christian Périgaud,
• Laurent Chaloin and
• Suzanne Peyrottes

Beilstein J. Org. Chem. 2016, 12, 1476–1486, doi:10.3762/bjoc.12.144

• ) [7], we were interested in studying the effect of replacing the nucleobase by a 1,2,3-triazole moiety, linked to various substituents, with the aim to retain or modulate essential elements for enzyme recognition. Indeed, the assembly of the triazole ring with various substituents confers to the final

Copper-catalyzed [3 + 2] cycloaddition of (phenylethynyl)di-p-tolylstibane with organic azides

• Mizuki Yamada,
• Mio Matsumura,
• Yuki Uchida,
• Masatoshi Kawahata,
• Yuki Murata,
• Naoki Kakusawa,
• Kentaro Yamaguchi and
• Shuji Yasuike

Beilstein J. Org. Chem. 2016, 12, 1309–1313, doi:10.3762/bjoc.12.123

• : cycloaddition; copper catalyst; ethynylstibane; organic azide; 1,2,3-triazole; Introduction The 1,3-dipolar azide–alkyne cycloaddition (AAC) has been effective for the synthesis of a wide variety of 1,2,3-triazoles [1]. However, this reaction has some limitations such as the requirement of high temperature and

• ) using 5 mol % of various Cu catalysts under aerobic conditions in THF at 60 °C (Table 1, entries 1–9). The results showed that CuBr was the best catalyst and gave the highest yield of the expected 5-stibano-1,2,3-triazole 3a (Table 1, entry 2). The reaction without the Cu catalyst did not afford 3a

• product (Table 1, entry 7). Heating of 5-stibano-1,2,3-triazole 3a in the presence of Cu(OAc)2 (5 mol %) under aerobic conditions in THF at 60 °C for 3 h afforded 4 in 91% yield. Furthermore, heating of 1 without 2a under the same conditions did not give the phenylacetylene and the starting compound was

Bi- and trinuclear copper(I) complexes of 1,2,3-triazole-tethered NHC ligands: synthesis, structure, and catalytic properties

• Shaojin Gu,
• Jiehao Du,
• Jingjing Huang,
• Huan Xia,
• Ling Yang,
• Weilin Xu and
• Chunxin Lu

Beilstein J. Org. Chem. 2016, 12, 863–873, doi:10.3762/bjoc.12.85

• Republic of China 10.3762/bjoc.12.85 Abstract A series of copper complexes (3–6) stabilized by 1,2,3-triazole-tethered N-heterocyclic carbene ligands have been prepared via simple reaction of imidazolium salts with copper powder in good yields. The structures of bi- and trinuclear copper complexes were

• atmosphere at room temperature. Keywords: copper; CuAAC reaction; : N-heterocylic carbene; 1,2,3-triazole; Introduction N-Heterocyclic carbene (NHC) have interesting electronic and structural properties. This resulted in their use as versatile ligands in organometallic chemistry and homogeneous catalysis

• , the easy synthesis and versatile coordination ability of 1,2,3-triazoles have led to an explosion of interest in coordination chemistry [21] and homogeneous catalysis [22][23][24][25][26]. Although a number of metal complexes containing 1,4-disubstituted-1,2,3-triazole ligands were well studied

Synthesis of bi- and bis-1,2,3-triazoles by copper-catalyzed Huisgen cycloaddition: A family of valuable products by click chemistry

• Zhan-Jiang Zheng,
• Ding Wang,
• Zheng Xu and
• Li-Wen Xu

Beilstein J. Org. Chem. 2015, 11, 2557–2576, doi:10.3762/bjoc.11.276

• different azides, followed by the sequential Swern oxidation and Ohira–Bestmann homologation provided the ethynyltriazole intermediate 9, finally another CuAAC resulted in the formation of unsymmetrical 4,4'-bi(1,2,3-triazole)s 10 (Scheme 4). The synthesis of 5,5'-bitriazoles Originally, in the research of

Supramolecular chemistry: from aromatic foldamers to solution-phase supramolecular organic frameworks

• Zhan-Ting Li

Beilstein J. Org. Chem. 2015, 11, 2057–2071, doi:10.3762/bjoc.11.222

• -triazole foldamers. In 2008, several groups independently described that the intermolecular C–H····Cl− hydrogen bonding could induce benzene-linked 1,2,3-triazole oligomers to form folded or helical conformations [61][62][63]. Currently, this family of foldamers have found wide applications in anion

• binding and design of photo-active molecular devices [64][65][66]. We were interested in developing inherently folded structural patterns for aromatic oligotriazole backbones. In 2009, Yuanyuan Zhu established that 1,5-diphenyl-1,2,3-triazole formed an intramolecular six-membered C–H····OMe hydrogen bonds

• confine the rotation of one single bond, while for the latter, it would confine two single bonds. Jiang and Huc and co-workers successfully utilized the five-membered N–H···Cl hydrogen bond to construct quinoline amide-derived double helices [53]. C–H····X (X = OR, F) hydrogen bonding-driven 1,2,3