Regioselective synthesis of heterocyclic N-sulfonyl amidines from heteroaromatic thioamides and sulfonyl azides

• Vladimir Ilkin,
• Vera Berseneva,
• Tetyana Beryozkina,
• Tatiana Glukhareva,
• Lidia Dianova,
• Wim Dehaen,
• Eugenia Seliverstova and
• Vasiliy Bakulev

Beilstein J. Org. Chem. 2020, 16, 2937–2947, doi:10.3762/bjoc.16.243

• -arylamino-1,2,3-triazole-4-N-sulfonylcarbimidamides. 2,5-Dithiocarbamoylpyridine reacts with sulfonyl azides to form a pyridine bearing two sulfonyl amidine groups. Keywords: amidines; Dimroth rearrangement; isoxazoles; sulfonyl thiazoles; thioamides; 1,2,3-triazoles; Introduction The biological activity

• interesting building blocks in organic synthesis [17][18][19][20] (Figure 1). An N-sulfonyl amidine was recently found to be a key group in acid–base-induced rearrangements of 1,2,3-triazoles and thiadiazoles [22]. A variety of methods have been developed for the synthesis of N-sulfonyl amidines. The most

• (Table 1, entry 11 and Table 2, entry 14). Thus solvent-free conditions, a temperature of 88 °C and a thioamide/azide ratio of 1:2.5 are optimal to prepare N-sulfonyl amidine 1c (entry 11, Table 1). Next, these optimized conditions were used for the synthesis of a small library of 1-alkyl-1,2,3-triazoles

Azidophosphonium salt-directed chemoselective synthesis of (E)/(Z)-cinnamyl-1H-triazoles and regiospecific access to bromomethylcoumarins from Morita–Baylis–Hillman adducts

• Soundararajan Karthikeyan,
• Radha Krishnan Shobana,
• Kamarajapurathu Raju Subimol,
• J. Helen Ratna Monica and
• Ayyanoth Karthik Krishna Kumar

Beilstein J. Org. Chem. 2020, 16, 1579–1587, doi:10.3762/bjoc.16.130

• )-catalysed straight forward protocol for synthesising structurally demanding (E)/(Z)-cinnamyl-1H-1,2,3-triazoles and halomethylcoumarins from MBH adducts. The novel methodology, efficient catalyst, and direct utilization of MBH adducts under mild reaction conditions qualify the reported procedures as

• comparatively afforded cinnamyl-1,4-disubstituted 1,2,3-triazoles at an improved yield compared to that of the methyl and ethyl counterparts. Notably, the MBH adducts derived from the para-bromo-, para-chloro-, and para-nitrobenzaldehydes favourably assisted the formation of the corresponding (E)-cinnamyl-1,4

• adducts. In contrast to the contending reports on the synthesis of 1,2,3-triazoles and halomethylcoumarins from MBH adducts, our studies report moderate reaction conditions with an improved yield. The above investigation provides a useful synthetic tool for synthetic organic chemists. The synthesis of

A systematic review on silica-, carbon-, and magnetic materials-supported copper species as efficient heterogeneous nanocatalysts in “click” reactions

• Pezhman Shiri and
• Jasem Aboonajmi

Beilstein J. Org. Chem. 2020, 16, 551–586, doi:10.3762/bjoc.16.52

• nanomagnetic catalyst for “click” reactions and tandem syntheses of 1,2,3-triazoles substituted at the 1- and 4-position in water [98]. The synthetic approach to 131 is shown in Scheme 28. First, magnetic CuFe2O4 nanoparticles 126 were treated with (3-chloropropyl)triethoxysilane in dry toluene to produce the

• magnetic nanoparticles CuFe2O4@starch (131). The catalytic activity of 131 was studied in the synthesis of 1,2,3-triazoles substituted at the 1- and 4-position by regioselective “click“ reactions of benzyl/alkyl bromides or arylboronic acids, sodium azide, and aromatic/alkyl alkynes in the presence of low

Halogen-bonding-induced diverse aggregation of 4,5-diiodo-1,2,3-triazolium salts with different anions

• Xingyu Xu,
• Shiqing Huang,
• Zengyu Zhang,
• Lei Cao and
• Xiaoyu Yan

Beilstein J. Org. Chem. 2020, 16, 78–87, doi:10.3762/bjoc.16.10

• chemistry, anion recognition, organocatalysis, materials science and tuning of biomolecular systems [17][18][19][20][21][22][23][24][25][26][27]. 1,2,3-Triazole-based XB-donors, such as 5-iodo-1,2,3-triazoles A [28][29][30][31][32][33] and 5-iodo-1,2,3-triazolium B [34][35][36][37] (Figure 1), are promising

• candidates for XB donors, which is mainly due to the ease of preparation via a copper-catalyzed click reaction between azide and alkyne [38][39]. 1,2,3-Triazoles and 1,2,3-triazolium-based XB activators have been found applications in catalytic reactions [40][41] and anion recognition [42]. Recently, we

Influence of the cis/trans configuration on the supramolecular aggregation of aryltriazoles

• Sara Tejera,
• Giada Caniglia,
• Rosa L. Dorta,
• Andrea Favero,
• Javier González-Platas and
• Jesús T. Vázquez

Beilstein J. Org. Chem. 2019, 15, 2881–2888, doi:10.3762/bjoc.15.282

• disposition to one of them (see Figure 5). Conclusion In summary, the capacity of di-1,4-disubstituted 1,2,3-triazoles to form gels was studied taking the dependence on the trans/cis configuration of the molecules into account. The results clearly show that compounds having the cis configuration are more

Diversity-oriented synthesis of spirothiazolidinediones and their biological evaluation

• Sambasivarao Kotha,
• Gaddamedi Sreevani,
• Lilya U. Dzhemileva,
• Milyausha M. Yunusbaeva,
• Usein M. Dzhemilev and
• Vladimir A. D’yakonov

Beilstein J. Org. Chem. 2019, 15, 2774–2781, doi:10.3762/bjoc.15.269

• compound 7e with 3-butyn-1-ol (16b) we were able to isolate the self trimerized derivative 20 as a minor product (Scheme 7). The ester derivative of thiazolidinedione 18 was hydrolyzed under AcOH, HCl reflux conditions to obtain N-acid derivative 22 in 90% yield (Scheme 8) [54]. Fused 1,2,3-triazoles

In water multicomponent synthesis of low-molecular-mass 4,7-dihydrotetrazolo[1,5-a]pyrimidines

• Irina G. Tkachenko,
• Sergey A. Komykhov,
• Vladimir I. Musatov,
• Svitlana V. Shishkina,
• Viktoriya V. Dyakonenko,
• Vladimir N. Shvets,
• Mikhail V. Diachkov,
• Valentyn A. Chebanov and
• Sergey M. Desenko

Beilstein J. Org. Chem. 2019, 15, 2390–2397, doi:10.3762/bjoc.15.231

• accessible by variation of the binucleophilic component 1 (instead of 1, 3-amino-1,2,4-triazole, 2-aminobenzimidazole, 3-aminopyrazoles, 4-amino-1,2,3-triazoles, etc. can be used [13]). However, a relatively low reactivity of amine 1 due to the electron deficiency of the tetrazole ring has been reported

Click chemistry towards thermally reversible photochromic 4,5-bisthiazolyl-1,2,3-triazoles

• Chenxia Zhang,
• Kaori Morinaka,
• Mahmut Kose,
• Takashi Ubukata and
• Yasushi Yokoyama

Beilstein J. Org. Chem. 2019, 15, 2161–2169, doi:10.3762/bjoc.15.213

• , Zonguldak Bülent Ecevit University, 67100, Zonguldak, Turkey 10.3762/bjoc.15.213 Abstract Three new diarylethenes were synthesized from 1,2-bis(5-methyl-2-(4-substituted-phenyl)thiazol-4-yl)ethyne and benzyl azide through Ru(I)-catalyzed Huisgen cyclization reactions. The 4,5-bisthiazolyl-1,2,3-triazoles

• triazole ring as one of the components of the hexatriene moiety has been reported to date. Accordingly, we decided to employ a Ru(I) catalyst to synthesize 4,5-diaryl-1-substituted-1,2,3-triazoles 1o–3o as possible photochromic compounds (Scheme 2). Results and Discussion Molecular design and synthesis As

1,2,3-Triazolium macrocycles in supramolecular chemistry

• Mastaneh Safarnejad Shad,
• Pulikkal Veettil Santhini and
• Wim Dehaen

Beilstein J. Org. Chem. 2019, 15, 2142–2155, doi:10.3762/bjoc.15.211

• macrocycles and focus on their application in different areas of supramolecular chemistry. The synthesis is mostly relying on the well-known “click reaction” (CuAAC) leading to 1,4-disubstituted 1,2,3-triazoles that then can be quaternized. Applications of triazolium macrocycles thus prepared include

• polymers etc. [14][15]. Noncovalent interactions play a dynamic role in the binding mechanism of triazoles as macrocyclic receptors. It has been reported that the combined effects of both an electron lone pair on the nitrogen of the heterocycle and the acidic C5–H proton make 1,2,3-triazoles interesting

Synthesis and fluorescent properties of N(9)-alkylated 2-amino-6-triazolylpurines and 7-deazapurines

• Andrejs Šišuļins,
• Jonas Bucevičius,
• Yu-Ting Tseng,
• Irina Novosjolova,
• Kaspars Traskovskis,
• Ērika Bizdēna,
• Huan-Tsung Chang,
• Sigitas Tumkevičius and
• Māris Turks

Beilstein J. Org. Chem. 2019, 15, 474–489, doi:10.3762/bjoc.15.41

• →4) followed by a SNAr process (4→5) which showcases the use of 1,2,3-triazoles as leaving groups. It is well established during our previous research in the purine nucleoside series that such an approach provides 6-amino-2-(1,2,3-triazol-1-yl) derivatives [25]. On the other hand, it was also

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

• Academy of Sciences, 155 Yangqiao Road West, Fuzhou, Fujian 350002, P. R. China University of Chinese academy of Science (UCAS), Beijing 100190, P. R. China 10.3762/bjoc.14.270 Abstract A copper-catalyzed azide–alkyne cycloaddition (CuAAC) reaction for the synthesis of 1,4-disubstituted 1,2,3-triazoles

• , making this protocol operationally simple. The Cu(I) catalyst not only participates in the alkyl diacyl peroxides decomposition to afford alkyl azides but also catalyzes the subsequent CuAAC reaction to produce the 1,2,3-triazoles. Keywords: alkyl diacyl peroxides; azidotrimethylsilane; click reaction

• ; copper catalysis; radical; 1,2,3-triazoles; Introduction The “click chemistry”, coined by K. B. Sharpless in 2001 [1], is a powerful chemical transformation that has rapidly orthogonalized traditional disciplinary boundaries. With the discovery of “click chemistry”, new fields have been opened for the

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

• ], 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

• -triazoles [25][26][27][28][29][30][31]. Yet, the developed methodologies for trisubstituted triazolochromenes generally lack a substituent on the 2-position, except for a sporadic methyl group which drastically lowers the yield and often the use of transition metals is needed [28]. The additional

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

• synthesis of 4-acyl-NH-1,2,3-triazoles has been accomplished with high efficiency through the cycloaddition reactions between N,N-dimethylenaminones and tosyl azide. This method is featured with extraordinary sustainability by employing water as the sole medium, free of any catalyst or additive

• numerous organic compounds [24][25][26][27][28]. The amazingly rapid and broad permeation of 1,2,3-triazoles to multidisciplinary areas can majorly be attributed to the occurrence of robust synthetic methods toward this heterocycle. The copper-catalyzed click [3 + 2] cycloaddition of azides and alkynes [29

• ][30][31][32], for example, has served enormously to the advances in both the preparation and application of 1,2,3-triazoles. In addition, the discovery of other metal-catalyzed alkyne–azide cycloadditions (MAAC) providing 1,2,3-triazoles with diverse substitution patterns triggers the continuous

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

• and bioactive molecules, but depending on the substituent identity, it can be inherently unstable due to Dimroth rearrangements. This study examined parameters governing the ring-degenerate rearrangement reactions of 1-substituted-4-imino-1,2,3-triazoles, expanding on trends first observed by L’abbé

• -containing molecules have also recently been shown to be useful synthons for preparing compounds with anticancer [33] and antituberculosis [34] properties. 1-Substituted-4-imino-1,2,3-triazole analogs are typically prepared from efficient condensation reactions of 1-substituted-4-formyl-1,2,3-triazoles

• -1,2,3-triazoles through a sequence of condensation, rearrangement and hydrolysis steps [42]. While this approach has found recent utility in preparing novel multidentate iminotriazole-based chelators [30][31][32], investigations exploring the parameters governing this rearrangement in greater detail

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

• -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

[3 + 2]-Cycloaddition reaction of sydnones with alkynes

• Veronika Hladíková,
• Jiří Váňa and
• Jiří Hanusek

Beilstein J. Org. Chem. 2018, 14, 1317–1348, doi:10.3762/bjoc.14.113

• (Scheme 6). A similar experiment was performed by Ohta et al. [60] five years later who irradiated single 3,4-diphenylsydnones and obtained the corresponding 2,4,5-triphenyl-1,2,3-triazoles in 21–24% yields (first misinterpreted as 1,3-diphenyldiazirine [61]). In the same year Angadiyavar and George [62

Sequential Ugi reaction/base-induced ring closing/IAAC protocol toward triazolobenzodiazepine-fused diketopiperazines and hydantoins

• Robby Vroemans,
• Fante Bamba,
• Jonas Winters,
• Joice Thomas,
• Jeroen Jacobs,
• Luc Van Meervelt,
• Jubi John and
• Wim Dehaen

Beilstein J. Org. Chem. 2018, 14, 626–633, doi:10.3762/bjoc.14.49

• of biological activities [56][57][58]. Owing to our interest in the chemistry of 1,2,3-triazoles [59][60][61][62][63][64][65][66][67][68][69][70][71][72] and the interesting biological activities of benzodiazepines and 2,5-diketopiperazines, we were motivated to develop a facile route towards

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

• = amino acid residues, aminoalkyl, 1,2,3 triazoles; n = 1, 2; R = H, Me, R' = OH, NHAc. Bivalent inhibitor designed and synthesised by Pickens et al. Bivalent inhibitor designed and synthesized by Arosio et al. Bivalent inhibitors designed and synthesised by Leaver and Liu. Bivalent and tetravalent

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

• reaction conditions and short reaction times, the advantage of CuAAC is the formation of 1,2,3-triazoles-1,4-disubstituted in a highly regioselective manner [41]. Recently, Cornec et al. [44] synthesized 4,6-dimethyl-2-(4-aryl-1H-1,2,3-triazol-1-yl)pyrimidines from azides using copper salts. The reaction

• involved the in situ reduction of the Cu(II) salt by sodium ascorbate. The reactions in this study were performed from the 1,3-dipoloar cycloaddition reaction catalyzed by Cu(I) [44] and the 1,4-disubstituted 1,2,3-triazoles 8a–c were acquired in excellent yields (Table 4). Although only compounds 6a–c

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

• an efficient regioselective generation of 1,4-disubstituted 1,2,3-triazoles [1][2][3]. After their discovery [1], click reactions affording 1,2,3-triazoles rapidly became important for simple and robust binding of versatile molecules and for the building of stable polymer structures [4]. At the same

• time, the 1,2,3-triazoles became the heterocycle of choice in drug discovery, due to their favourable pharmacokinetic and safety profiles, hydrogen-bonding capability, moderate dipole moment, rigidity and stability under in vivo conditions [5][6]. Also, the ability of 1,2,3-triazoles to act as amide

Mechanochemical synthesis of small organic molecules

• Tapas Kumar Achar,
• Anima Bose and
• Prasenjit Mal

Beilstein J. Org. Chem. 2017, 13, 1907–1931, doi:10.3762/bjoc.13.186

• using carboxymethylimidazole-based ionic-liquid-coated ZnO nano particles as catalyst (Scheme 36) [149]. The catalyst worked efficiently till to the fifth cycle after regeneration by filtration of product and washing with methanol. The method was scalable up to using of 8 g of o-phenylene diamine. 1,2,3

• -Triazoles have important applications in pharmaceutical chemistry [150] and traditionally they are prepared by 1,3-dipolar cycloaddition reactions at high temperature, long reaction times and produce low yield with multiple products [151]. In 2013, Ranu and co-workers reported mechanochemical synthesis of

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