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

• ; organocatalysis; organoselenium compounds; sonochemistry; 1,2,3-triazoles; Introduction Substituted 1,2,3-triazoles are an interesting class of heterocyclic compounds distinguished by their biological activities [1][2][3] as well as in various fields of chemistry [4][5][6][7][8][9][10][11][12][13][14][15]. The

• 1,2,3-triazoles [33][34][35][36][37]. Selanyltriazoyl carboxylates, carboxamides, carbonitriles or sulfones were synthesized in good to excellent yields using catalytic amounts of an organocatalyst. Organoselenium compounds are attractive synthetic targets because of their selective reactions [38][39

• ][40][41][42][43], photophysical properties [44][45][46][47][48][49] and interesting biological activities [50][51][52]. An interesting class of molecules are the selanyl-1,2,3-triazoles [53][54][55][56][57][58][59][60][61] which can present some biological applications. As example, 4-phenyl-1

Synthesis of 1-indanones with a broad range of biological activity

• Marika Turek,
• Dorota Szczęsna,
• Marek Koprowski and
• Piotr Bałczewski

Beilstein J. Org. Chem. 2017, 13, 451–494, doi:10.3762/bjoc.13.48

• of palladium catalyst and gaseous oxygen as the terminal oxidant (Scheme 65). 1.8 From other compounds In 2016, Shi et al. have developed an unique, conditions-controlled [Rh2(esp)2] (esp = α,α,α’,α’-tetramethyl-1,3-benzenedipropionic acid)-catalyzed reaction of N-sulfonyl-1,2,3-triazoles 235 leading

A postsynthetically 2’-“clickable” uridine with arabino configuration and its application for fluorescent labeling and imaging of DNA

• Heidi-Kristin Walter,
• Bettina Olshausen,
• Ute Schepers and
• Hans-Achim Wagenknecht

Beilstein J. Org. Chem. 2017, 13, 127–137, doi:10.3762/bjoc.13.16

• not present in nucleic acids [2][3][4][5]. Although Huisgen described the uncatalyzed reaction yielding 1,2,3-triazoles already in the 1960s [6], the bioorthogonality with respect to proteins and nucleic acids emerged after Sharpless [7] and Meldal [8] had reported that catalysis by Cu(I) enhances not

Iodination of carbohydrate-derived 1,2-oxazines to enantiopure 5-iodo-3,6-dihydro-2H-1,2-oxazines and subsequent palladium-catalyzed cross-coupling reactions

• Michal Medvecký,
• Igor Linder,
• Luise Schefzig,
• Hans-Ulrich Reissig and
• Reinhold Zimmer

Beilstein J. Org. Chem. 2016, 12, 2898–2905, doi:10.3762/bjoc.12.289

• 1,2,3-triazoles [50]. After the desilylation of syn-5 using potassium fluoride in methanol (Scheme 8) the resulting mono-substituted alkyne was subjected to an established protocol using benzyl azide, copper(I) iodide, triethylamine and TBTA [51] (for a recent review see [52]). The cycloaddition

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

• bonds was estimated to be −16.8 kcal/mol whereas the corresponding binding energy for the H2O/Cl− complex was determined to be −15.4 kcal/mol. Electron-deficient heterocyclic compounds such as 1,2,3-triazoles may also serve as strong C–H hydrogen bond donors. Substituted 1,2,3-triazoles possess a

• acceptors and also act as electron-withdrawing substituents when attached to other aromatic rings thus enhancing benzene’s ring C–H hydrogen bonding [29][30][31]. Recent studies by the Flood group and the Craig group suggested that receptors containing arylated 1,2,3-triazoles could form stable

• 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

Synthesis and NMR studies of malonyl-linked glycoconjugates of N-(2-aminoethyl)glycine. Building blocks for the construction of combinatorial glycopeptide libraries

• Markus Nörrlinger,
• Sven Hafner and
• Thomas Ziegler

Beilstein J. Org. Chem. 2016, 12, 1939–1948, doi:10.3762/bjoc.12.183

• either simple alkyl chains [15][16], amino alcohols [17][18] or 1,2,3-triazoles [19][20][21]. These building blocks were used for automated SPOT synthesis on a cellulose surface in order to construct complex glycoconjugates which are able to specifically bind to lectins [15][18][20]. In continuation of

Dinuclear thiazolylidene copper complex as highly active catalyst for azid–alkyne cycloadditions

• Anne L. Schöffler,
• Ata Makarem,
• Frank Rominger and
• Bernd F. Straub

Beilstein J. Org. Chem. 2016, 12, 1566–1572, doi:10.3762/bjoc.12.151

• [1][2][3]. In 2002, the research groups of Meldal and Sharpless independently discovered the strongly rate-enhancing effect of copper(I) salts for azide–alkyne cycloadditions. The 1,4-disubstituted 1,2,3-triazoles are formed exclusively with essentially quantitative conversion and under mild reaction

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

• Cancérologie de Lyon, 69008 Lyon, France 10.3762/bjoc.12.144 Abstract A series of seventeen β-hydroxyphosphonate ribonucleoside analogues containing 4-substituted-1,2,3-triazoles was synthesized and fully characterized. Such compounds were designed as potential inhibitors of the cytosolic 5’-nucleotidase II

• the alkyne employed. Herein, we report the results of the synthesis and in vitro biological evaluation on the purified human recombinant cN-II of a series of beta-hydroxyphosphonate ribonucleosides including as nucleobases 4-substituted-1,2,3-triazoles (Figure 1). Results and Discussion Chemistry The

• and 5 demonstrates that cycloaddition of terminal alkynes catalysed by Cu(I) were highly regioselective and led to 4-substituted-1,2,3-triazoles in the β-hydroxyphosphonate series. Then, on the basis of the study reported by Hudson et al., we performed extensive 2D-NMR experiments on compounds 3h and

Application of Cu(I)-catalyzed azide–alkyne cycloaddition for the design and synthesis of sequence specific probes targeting double-stranded DNA

• Svetlana V. Vasilyeva,
• Vyacheslav V. Filichev and
• Alexandre S. Boutorine

Beilstein J. Org. Chem. 2016, 12, 1348–1360, doi:10.3762/bjoc.12.128

• of 1,2,3-triazoles can connect several components in one molecule [25][26]. CuAAC belongs to the class of chemical processes called “click-chemistry” and it is also a biorthogonal reaction because functional groups of natural biopolymers are not affected and do not participate in chemical

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

• University, 1314-1 Shido, Sanuki, Kagawa 769-2193, Japan Faculty of Pharmaceutical Sciences, Hokuriku University, Ho-3 Kanagawa-machi, Kanazawa 920-1181, Japan 10.3762/bjoc.12.123 Abstract Trisubstituted 5-stibano-1H-1,2,3-triazoles were synthesized in moderate to excellent yields by the Cu-catalyzed [3 + 2

• : 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

• -disubstituted 1,2,3-triazoles. Since then, the CuAAC has been widely applied in organic synthesis [4][5][6][7][8][9][10][11][12], molecular biology [13][14][15][16][17], and materials science [18][19][20]. There are many reports of CuAACs by using terminal alkynes (including metal acetylides) [4][5][6][7][8][9

Multicomponent reactions: A simple and efficient route to heterocyclic phosphonates

• Mohammad Haji

Beilstein J. Org. Chem. 2016, 12, 1269–1301, doi:10.3762/bjoc.12.121

• process involves the 1,3-dipolar cycloaddition of alkynes 182 with in situ generated nitrone 185 to afford isoxazolines 186 which rapidly rearrange to aziridinylphosphonates 183. An efficient method for the synthesis of 1,2,3-triazoles is the copper(I)-catalyzed Husigen cycloaddition of azides with

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

• , 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

• , reports concerning their preparation and use of 1,4-disubstituted-1,2,3-triazoles bearing NHC ligands are rare [22][23]. Elsevier et al. [23] reported several of palladium(II) complexes containing a heterobidentate N-heterocyclic carbene-triazolyl ligand. These palladium(II) complexes are active

• via reacting methyl propiolate with (azidomethyl)benzene. This promising catalytic behavior of complex 4 prompted us to extend our studies toward a one-pot synthesis of 1,2,3-triazoles from alkyl halides, sodium azide, and alkynes. The three-component version has already been successfully performed

Creating molecular macrocycles for anion recognition

• Amar H. Flood

Beilstein J. Org. Chem. 2016, 12, 611–627, doi:10.3762/bjoc.12.60

• activity surrounding 1,2,3-triazoles made using click chemistry; and the same triazoles are responsible for anion capture. Mistakes made and lessons learnt in anion recognition provide deeper understanding that, together with theory, now provides for computer-aided receptor design. The lessons are acted

• microscopy (STM) imaging. Their shape persistence makes them ideal for the study of structure–property relationships to enable deep understanding of anion recognition phenomena. The identification of 1,2,3-triazoles as linkers, ligands and building blocks. The synthetic creation of macrocycles sets the scene

• it was an old reaction, the Huisgen cycloaddition, made good (regioselective) with the aid of copper catalysis. Taking that idea on face value, I reasoned that click chemistry was a new and extremely effective way to make 1,2,3-triazoles. It is not often that either new or newly refined reactions

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

• Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, P. R. China 10.3762/bjoc.11.276 Abstract The Cu(I)-catalyzed azide-alkyne cycloaddition reaction, also known as click chemistry, has become a useful tool for the facile formation of 1,2,3-triazoles

• . Specifically, the utility of this reaction has been demonstrated by the synthesis of structurally diverse bi- and bis-1,2,3-triazoles. The present review focuses on the synthesis of such bi- and bistriazoles and the importance of using copper-promoted click chemistry (CuAAC) for such transformations. In

• instability. Later in 2009, Fiandanese et al. proposed that unsymmetrically substituted 4,4'-bi-1,2,3-triazoles can be prepared in an easy manner [18]: starting from 1-trimethylsilyl-1,3-butadiyne (4) the 4-(silylalkynyl)-1,2,3-triazoles 5 can be obtained after reaction with substituted azides catalyzed by Cu

Synthesis, antimicrobial and cytotoxicity evaluation of new cholesterol congeners

• Mohamed Ramadan El Sayed Aly,
• Hosam Ali Saad and
• Shams Hashim Abdel-Hafez

Beilstein J. Org. Chem. 2015, 11, 1922–1932, doi:10.3762/bjoc.11.208

• , hydroxyalkyl-1,2,3-triazoles were reported as valuable pharmacophores [36]. The products were isolated in good yields and the H-5 signal of triazole (1H NMR) could be observed as a singlet at δ ≈ 7.5 ppm. Compound 11a was further converted into the corresponding bromo derivative 12 in good yield under the same

Synthesis and spectroscopic properties of β-triazoloporphyrin–xanthone dyads

• Dileep Kumar Singh and
• Mahendra Nath

Beilstein J. Org. Chem. 2015, 11, 1434–1440, doi:10.3762/bjoc.11.155

• ] including anti-oxidative [35], antihypertensive [36], anti-inflammatory [37] and antiplatelet agents [38]. They have also been used as fluorophores and exhibited good fluorescence properties when attached to a triazole ring [39][40]. Owing to the biological significance of porphyrins, 1,2,3-triazoles and

Synthesis of alpha-tetrasubstituted triazoles by copper-catalyzed silyl deprotection/azide cycloaddition

• Zachary L. Palchak,
• Paula T. Nguyen and
• Catharine H. Larsen

Beilstein J. Org. Chem. 2015, 11, 1425–1433, doi:10.3762/bjoc.11.154

• ; copper catalysis; multicomponent reactions; tetrasubstituted carbon; triazole; Introduction 1,2,3-Triazoles demonstrate wide spread application in biological systems and drug development [1][2][3][4][5][6][7][8][9][10][11][12]. Copper-catalyzed azide–alkyne cycloadditions (CuAAC) regioselectively

• introduce a wide variety of substituents on 1,4-disubstituted 1,2,3-triazoles from the organic azide or terminal alkyne starting materials [1][2]. These Huisgen reactions [13] facilitate rapid drug screening by allowing for tracking in biological systems and the exploration of structure-activity

Sequential decarboxylative azide–alkyne cycloaddition and dehydrogenative coupling reactions: one-pot synthesis of polycyclic fused triazoles

• Kuppusamy Bharathimohan,
• Thanasekaran Ponpandian,
• A. Jafar Ahamed and
• Nattamai Bhuvanesh

Beilstein J. Org. Chem. 2014, 10, 3031–3037, doi:10.3762/bjoc.10.321

• cycloaddition, CuAAC) between an organic azide and a terminal alkyne is a well-established strategy for the construction of 1,4-disubstituted 1,2,3-triazoles [1][2][3][4]. In a recent development, this decarboxylative coupling reaction was well documented for the generation of C–C bonds [5]. This method has

• followed by C–H functionalization (Scheme 1). Specifically, they demonstrated a C–H functionalization of an indole nucleus with 5-iodo-1,2,3-triazoles. In the present study, we replaced the 5-iodo-1,2,3-triazoles with 5H-1,2,3-triazoles with intramolecular sp2 C–H/C–H cross coupling reaction. To the best

Synthesis of aromatic glycoconjugates. Building blocks for the construction of combinatorial glycopeptide libraries

• Markus Nörrlinger and
• Thomas Ziegler

Beilstein J. Org. Chem. 2014, 10, 2453–2460, doi:10.3762/bjoc.10.256

• focus was on glycosylated amino acid building blocks derived from aspartic acid and from the PNA-like N-(2-aminoethyl)glycine (AEG) backbone to which the sugar moieties were attached through either simple alkyl chains [5][6], amino alcohols [7][8] or 1,2,3-triazoles [9][10][11]. These building blocks

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

• synthesis of 1-alkoxy-1H-benzo[d][1,2,3]triazoles. Three possible mechanisms for the reaction of BOP with oxygen nucleophiles. Possible products in the [18O]-labeling experiments. Two possible products from the reaction of At-OTs with MeOH. Synthesis of acyclic nucleoside-like compounds. Formation of Bt-OR

Design and synthesis of multivalent neoglycoconjugates by click conjugations

• Feiqing Ding,
• Li Ji,
• Ronny William,
• Hua Chai and
• Xue-Wei Liu

Beilstein J. Org. Chem. 2014, 10, 1325–1332, doi:10.3762/bjoc.10.134

• the ease of purification, 1,4-disubstituted-1,2,3-triazoles, the regiospecific product of this reaction, exhibit similarities to the ubiquitous amide moiety found in nature. However, unlike amides, the triazole moiety proved to be robust and resistant to chemical and enzymatic cleavage [17][18][19][20

Isocyanide-based multicomponent reactions towards cyclic constrained peptidomimetics

• Gijs Koopmanschap,
• Eelco Ruijter and
• Romano V.A. Orru

Beilstein J. Org. Chem. 2014, 10, 544–598, doi:10.3762/bjoc.10.50

• of amide bonds by 1,2,3-triazoles, especially the 1,4-disubstituted isomer, provided a wide variety of biological active peptidomimetics. Peptidomimetics containing these triazole cores can serve as blood components [77], anticancer medications [78], inhibitors of cysteine [79] and HIV-1 proteases

• [80][81][82]. The relative planarity of 1,2,3-triazoles, the strong dipole moment (~5 D) and the ability to both donate and accept hydrogen bonds indicate the physicochemical similarities with amide bonds (Scheme 25), however, they are inert towards oxidation, hydrolysis and enzymatic degradation [88

Advancements in the mechanistic understanding of the copper-catalyzed azide–alkyne cycloaddition

• Regina Berg and
• Bernd F. Straub

Beilstein J. Org. Chem. 2013, 9, 2715–2750, doi:10.3762/bjoc.9.308

• . The classical thermal Huisgen cycloaddition of organoazides and alkynes proceeds very slowly even at high temperatures, and gives a mixture of 1,4- and 1,5-disubstituted 1,2,3-triazoles (Scheme 1). In 2002, the groups of Meldal and Sharpless independently discovered a copper-catalyzed variant of

• Huisgen’s azide–alkyne cycloaddition (CuAAC reaction). In fact, the catalytic effect of copper ions had first been mentioned by L’Abbé in 1984 [7], but had henceforth been overlooked until Meldal presented a copper(I)-catalyzed solid-phase synthesis of 1,2,3-triazoles. In this procedure, the terminal alkyne

• 1,2,3-triazoles. In 2005, the group of Rutjes reported the synthesis of 5-bromo-1,4-disubstituted-1,2,3-triazoles starting from 1-bromoalkynes [155]. In their optimized procedure, the bromoalkyne reacts with an azide in the presence of 5 mol % copper(I) iodide and 5 mol % copper(II) acetate in THF at 50

Efficient continuous-flow synthesis of novel 1,2,3-triazole-substituted β-aminocyclohexanecarboxylic acid derivatives with gram-scale production

• Sándor B. Ötvös,
• Ádám Georgiádes,
• István M. Mándity,
• Lóránd Kiss and
• Ferenc Fülöp

Beilstein J. Org. Chem. 2013, 9, 1508–1516, doi:10.3762/bjoc.9.172

• recent years, triazole-containing compounds have become potential targets for drug discovery [1][2]. A large number of 1,2,3-triazoles exhibit various biological effects [3], e.g., antiviral (1), antibacterial (2), antifungal (3) and anticancer (4) activities [4][5][6][7] (Figure 1). The 1,2,3-triazole

• applications in numerous other areas of modern chemical sciences, such as bioconjugation [13], supramolecular chemistry, [14] and polymer sciences [15]. Probably the most useful and powerful procedure for the synthesis of 1,2,3-triazoles is the Huisgen 1,3-dipolar cycloaddition of organic azides with

• cases; Table 1, entries 3 and 4). 1,4,5-Trisubstituted 1,2,3-triazoles are of notable importance in drug discovery. For example, several 1,2,3-triazole-4,5-dicarboxylates display significant antituberculotic activity in vitro [69]. Thus, a nonterminal alkyne, diethyl acetylenedicarboxylate, was

A facile, rapid, one-pot regio/stereoselective synthesis of 2-iminothiazolidin-4-ones under solvent/scavenger-free conditions

• Murugan Sathishkumar,
• Sangaraiah Nagarajan,
• Poovan Shanmugavelan,
• Murugan Dinesh and
• Alagusundaram Ponnuswamy

Beilstein J. Org. Chem. 2013, 9, 689–697, doi:10.3762/bjoc.9.78

• environmentally friendly methodologies for the synthesis of 2-iminothiazolidin-4-ones is worth attempting. In this regard, and in continuation of our recent reports on the solvent-free synthesis of amides [19][20], thioamides [21], cyclic imides [22], thiazolidin-4-ones [23], spirothiazolidin-4-ones [24], 1,2,3

• -triazoles [25], 1,2,3-triazolylchalcones [26], and 1,2,3-triazolyldihydropyrimidine-2-thiones [27], we herein present a one-pot solvent/scavenger-free synthetic protocol for 2-iminothiazolidin-4-ones. This environmentally benign method avoids toxic organic solvents and acid scavengers, the details of which