Microwave-assisted efficient and facile synthesis of tetramic acid derivatives via a one-pot post-Ugi cascade reaction

• Yong Li,
• Zheng Huang,
• Jia Xu,
• Yong Ding,
• Dian-Yong Tang,
• Jie Lei,
• Hong-yu Li,
• Zhong-Zhu Chen and
• Zhi-Gang Xu

Beilstein J. Org. Chem. 2020, 16, 663–669, doi:10.3762/bjoc.16.63

• has the potential to produce a large number of tetramic acid analogues, which cannot be easily accessed by the classic synthetic methods. Keywords: Dieckmann cyclization; multicomponent reactions; nitrogen heterocycles; one-pot reaction; Ugi reaction; Introduction Nitrogen-containing heterocycles

Rhodium-catalyzed reductive carbonylation of aryl iodides to arylaldehydes with syngas

• Zhenghui Liu,
• Peng Wang,
• Zhenzhong Yan,
• Suqing Chen,
• Dongkun Yu,
• Xinhui Zhao and
• Tiancheng Mu

Beilstein J. Org. Chem. 2020, 16, 645–656, doi:10.3762/bjoc.16.61

• friendly and highly effective synthetic methods has been a significant goal of research [1][2][3][4][5]. In this aspect, effective catalytic systems and organometallic chemistry are suitable technologies to accomplish these goals. Carbonylation processes are important transformations in the refinement and

Regioselectively α- and β-alkynylated BODIPY dyes via gold(I)-catalyzed direct C–H functionalization and their photophysical properties

• Takahide Shimada,
• Shigeki Mori,
• Masatoshi Ishida and
• Hiroyuki Furuta

Beilstein J. Org. Chem. 2020, 16, 587–595, doi:10.3762/bjoc.16.53

• extensively developed to tune the optoelectronic properties [21]. Therefore, the development of more efficient and shorter step synthetic methods for the BODIPY derivatives, such as direct C–H functionalizations (e.g., arylation [22][23][24][25][26][27][28], annulation [29], olefination [30], styrylation [31

Efficient synthesis of 3,6,13,16-tetrasubstituted-tetrabenzo[a,d,j,m]coronenes by selective C–H/C–O arylations of anthraquinone derivatives

• Seiya Terai,
• Yuki Sato,
• Takuya Kochi and
• Fumitoshi Kakiuchi

Beilstein J. Org. Chem. 2020, 16, 544–550, doi:10.3762/bjoc.16.51

• from researchers due to their high potential as organic optoelectronic materials [1][2][3] and great efforts have been devoted to the development of their efficient synthetic methods [4]. One of the important steps in most of the PAH syntheses is the construction of carbon–carbon bonds between aryl

• ,m]coronenes having two different types of substituents. Coronene derivatives such as hexabenzocoronenes and ovalenes have been extensively studied because of their optoelectronic and self-assembling properties [34][35][36][37][38][39][40][41][42][43][44]. Various synthetic methods have been

Synthesis of six-membered silacycles by borane-catalyzed double sila-Friedel–Crafts reaction

• Yafang Dong,
• Masahiko Sakai,
• Kazuto Fuji,
• Kohei Sekine and
• Yoichiro Kuninobu

Beilstein J. Org. Chem. 2020, 16, 409–414, doi:10.3762/bjoc.16.39

• in terms of the functional group tolerance and versatility of these previously reported synthetic methods due to the use of a stoichiometric amount of the organolithium reagents. In addition, despite these contributions, catalytic reaction systems have not been developed as much [26][27]. The sila

• . Synthetic methods of six-membered silacyclic compounds. Scope of dihydrosilanes. Conditions: a: conditions B (Table 1, entry 5); b: conditions A (Table 1, entry 3). Scope of diaryl ether and diaryl thioether derivatives. Conditions: a: conditions B (Table 1, entry 5); b: conditions A (Table 1, entry 3). c

Architecture and synthesis of P,N-heterocyclic phosphine ligands

• Wisdom A. Munzeiwa,
• Bernard Omondi and
• Vincent O. Nyamori

Beilstein J. Org. Chem. 2020, 16, 362–383, doi:10.3762/bjoc.16.35

• inactive phosphines ascribed to pseudo rotation of the pentacoordinated transition intermediates [52]. Despite this, researchers have synthesized many efficient phosphine ligands, though fast and easy synthetic methods which are principal in the development of flexible ligands are still needed. Review

• sites has been reviewed. Different synthetic methods have been included which vary for different ligand systems. Some of the procedures satisfy more or less the following benchmarks, i.e., higher isolated yields and optical purity, allow variable substitution around the skeleton to adjust electronic and

Efficient method for propargylation of aldehydes promoted by allenylboron compounds under microwave irradiation

• Jucleiton J. R. Freitas,
• Queila P. S. B. Freitas,
• Silvia R. C. P. Andrade,
• Juliano C. R. Freitas,
• Roberta A. Oliveira and
• Paulo H. Menezes

Beilstein J. Org. Chem. 2020, 16, 168–174, doi:10.3762/bjoc.16.19

• small proportion of the corresponding regioisomer in some cases, in the development of new synthetic methods, it is desirable that it gives the corresponding product as a single compound. Our group described the synthesis of homopropargylic alcohols using potassium allenyltrifluoroborate as the

The reaction of arylmethyl isocyanides and arylmethylamines with xanthate esters: a facile and unexpected synthesis of carbamothioates

• Narasimhamurthy Rajeev,
• Toreshettahally R. Swaroop,
• Ahmad I. Alrawashdeh,
• Shofiur Rahman,
• Abdullah Alodhayb,
• Seegehalli M. Anil,
• Kuppalli R. Kiran,
• Chandra,
• Paris E. Georghiou,
• Kanchugarakoppal S. Rangappa and
• Maralinganadoddi P. Sadashiva

Beilstein J. Org. Chem. 2020, 16, 159–167, doi:10.3762/bjoc.16.18

• ], iron nanoparticle-catalyzed reactions of 2-naphthol with benzaldehyde and some of its derivatives with thiourea [22], isothiocyanato oxindoles with ketones [23], ammonium isothiocyanates with chalcones [24], and α-isothiocyanato esters with α-keto amides [25]. Among the synthetic methods available for

• been synthesized from xanthate esters, but the methodology described is limited to only a few examples with aliphatic substituents and furthermore suffers from a tedious isolation protocol [18]. As a part of our work on the development of new synthetic methods [26][27][28][29][30], we have recently

• [7], insecticides (cartap) [8], and herbicides [9]. They are also used as key intermediates in the generation of carbonyl sulfide/hydrogen sulfide [10], the synthesis of isothiocyanates [11], asymmetric thioureas [12], and thiazolidine/thiaoxazine [13]. Therefore, as a result, numerous synthetic

SnCl₄-catalyzed solvent-free acetolysis of 2,7-anhydrosialic acid derivatives

• Kesatebrhan Haile Asressu and
• Cheng-Chung Wang

Beilstein J. Org. Chem. 2019, 15, 2990–2999, doi:10.3762/bjoc.15.295

• galactosyl α(1→4) to Neu5Ac, and intramolecularly C-7-to-C-2-linked (via oxygen), forming 2,7-anhydro-Neu5Ac [4][5][6]. Owing to the substantial role of sialic acids in biological systems, numerous synthetic methods have been described in the literature [7][8][9][10][11][12][13][14][15][16]. 2,7-Anhydro

Construction of trisubstituted chromone skeletons carrying electron-withdrawing groups via PhIO-mediated dehydrogenation and its application to the synthesis of frutinone A

• Qiao Li,
• Chen Zhuang,
• Donghua Wang,
• Wei Zhang,
• Rongxuan Jia,
• Fengxia Sun,
• Yilin Zhang and
• Yunfei Du

Beilstein J. Org. Chem. 2019, 15, 2958–2965, doi:10.3762/bjoc.15.291

• to possess antiviral and antispasmodic effects (Figure 1) [28]. All of these pharmaceutical agents bear a chromone framework in their respective chemical structure. Since the chromone derivatives have a variety of biological activities, developing synthetic methods for efficient construction of the

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

• -peroxisome proliferator activated receptor (PPARγ) [23][24]. The discovery of biological activities of TZDs and the development of medicinal and pharmaceutical chemistry has led to an enhanced interest in the design of new synthetic methods for the preparation of various TZDs. The most conventional method of

A combinatorial approach to improving the performance of azoarene photoswitches

• Joaquin Calbo,
• Aditya R. Thawani,
• Rosina S. L. Gibson,
• Andrew J. P. White and
• Matthew J. Fuchter

Beilstein J. Org. Chem. 2019, 15, 2753–2764, doi:10.3762/bjoc.15.266

• absorption bands, calculated as the λmax subtraction between E and Z-isomers, and photostationary-state-conversion efficiency (PSS in %). Supporting Information Raw data can be found at doi:10.14469/hpc/6203 Supporting Information File 535: Theoretical calculations, synthetic methods, experimental

A review of asymmetric synthetic organic electrochemistry and electrocatalysis: concepts, applications, recent developments and future directions

• Munmun Ghosh,
• Valmik S. Shinde and
• Magnus Rueping

Beilstein J. Org. Chem. 2019, 15, 2710–2746, doi:10.3762/bjoc.15.264

• Waldvogel’s group focused on the advancements achieved in the development of synthetic methods as well as applications of organic electrosynthesis reported since 2000 [13][14]. Moreover, in his recent article, Moeller have nicely demonstrated that both physical and organic chemistry are indispensable for

• asymmetric electrocatalytic reactions. Review Classification and systematic description of chiral inductors Transformations of achiral organic substrates into chiral products by electrochemical synthetic methods require the active participation of an external source of chirality. Organic chemists working in

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

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 are a class of steroid-based receptors which can host polar molecules in nonpolar solvents because of their amphiphilic nature. As a result, their design and synthesis has been a topic of substantial research interest in supramolecular chemistry [32][33]. Various synthetic methods have been

Friedel–Crafts approach to the one-pot synthesis of methoxy-substituted thioxanthylium salts

• Kenta Tanaka,
• Yuta Tanaka,
• Mami Kishimoto,
• Yujiro Hoshino and
• Kiyoshi Honda

Beilstein J. Org. Chem. 2019, 15, 2105–2112, doi:10.3762/bjoc.15.208

• useful properties, several research groups have developed methodologies to synthesize them. The typical synthetic methods for thioxanthylium salts include the reaction of thioxanthone with aryl bromide in the presence of n-butyllithium or Grignard reagents followed by dehydration by acids such as

Synthesis of benzo[d]imidazo[2,1-b]benzoselenoazoles: Cs₂CO₃-mediated cyclization of 1-(2-bromoaryl)benzimidazoles with selenium

• Mio Matsumura,
• Yuki Kitamura,
• Arisa Yamauchi,
• Yoshitaka Kanazawa,
• Yuki Murata,
• Tadashi Hyodo,
• Kentaro Yamaguchi and
• Shuji Yasuike

Beilstein J. Org. Chem. 2019, 15, 2029–2035, doi:10.3762/bjoc.15.199

• . Reaction conditions: 1 (0.5 mmol), Se (1 mmol), Cs2CO3 (1 mmol), DMF (1 mL), 150 °C, 24 h. Isolated yield. Absorption spectra of selected compounds (2a, 10 and 11) in CHCl3. Previously reported synthetic methods for the preparation of imidazo[2,1-b]selenoazoles. Control reactions. Proposed mechanism

Synthesis of ([1,2,4]triazolo[4,3-a]pyridin-3-ylmethyl)phosphonates and their benzo derivatives via 5-exo-dig cyclization

• Aleksandr S. Krylov,
• Artem A. Petrosian,
• Julia L. Piterskaya,
• Nataly I. Svintsitskaya and
• Albina V. Dogadina

Beilstein J. Org. Chem. 2019, 15, 1563–1568, doi:10.3762/bjoc.15.159

• , hypervalent iodine reagents, etc. The synthetic methods towards diverse [1,2,4]triazolo[3,4-a]pyridines have been reviewed in detail [12][13]. It should be noted that the use of acetylene species to create this heterocycle (including triazole ring) is presented only by few examples. There has been reported

Multicomponent reactions (MCRs): a useful access to the synthesis of benzo-fused γ-lactams

• Edorta Martínez de Marigorta,
• Jesús M. de Los Santos,
• Ana M. Ochoa de Retana,
• Javier Vicario and
• Francisco Palacios

Beilstein J. Org. Chem. 2019, 15, 1065–1085, doi:10.3762/bjoc.15.104

• this review. Review Isoindolinones An extensive range of synthetic methods have been developed for the preparation of isoindolinone derivatives [72][73][74][75], although only a few make use of multicomponent approaches. Most of the multicomponent syntheses of this type of heterocycles employ a benzoic

• the large-scale synthesis in pharmaceutical laboratories and industry. Nevertheless, among the multicomponent synthetic methods available for the preparation of isoindolinones II and 2-oxindoles III, only one is enantioselective, even though many of the reactions described in this review involve the

SO₂F₂-mediated transformation of 2'-hydroxyacetophenones to benzo-oxetes

• Revathi Lekkala,
• Ravindar Lekkala,
• Balakrishna Moku,
• K. P. Rakesh and
• Hua-Li Qin

Beilstein J. Org. Chem. 2019, 15, 976–980, doi:10.3762/bjoc.15.95

• satisfactory yields from the functionalized acyclic precursors generally requires good leaving groups and anions. A large number of synthetic methods has been described for the formation of oxetane derivatives and among them, two common strategies are widely applied. The first strategy engages an

Mechanochemical synthesis of poly(trimethylene carbonate)s: an example of rate acceleration

• Sora Park and
• Jeung Gon Kim

Beilstein J. Org. Chem. 2019, 15, 963–970, doi:10.3762/bjoc.15.93

• Discussion Aliphatic polycarbonates are found in many biomedical applications since they have many desirable properties such as high biocompatibility, easy degradation, good mechanical properties, and low toxicity [21][22][23]. Many synthetic methods have been developed, and the chain-growth ring-opening

An efficient and concise access to 2-amino-4H-benzothiopyran-4-one derivatives

• Peng Li,
• Yongqi Wu,
• Tingting Zhang,
• Chen Ma,
• Ziyun Lin,
• Gang Li and
• Haihong Huang

Beilstein J. Org. Chem. 2019, 15, 703–709, doi:10.3762/bjoc.15.65

• ]. Compared to the versatile synthetic methods leading to 2-aminobenzopyranone derivatives, the approaches to 2-aminobenzothiopyranones are somewhat limited. Some simple 2-aminobenzothiopyranones have been obtained by the cyclization of 2-thiobenzoylacetonitrile treated with a strong acid (method A, Scheme 1

• ) [6][7], or through the reduction of 2-nitrobenzothiopyranones with sodium dithionite (method B, Scheme 1) [8]. Apparently, synthetic methods to afford N-substituted 2-aminobenzothiopyranones are less well developed. The first example of an interchange of a 2-methylthio substituent for a nitrogen

Synthesis of 2H-furo[2,3-c]pyrazole ring systems through silver(I) ion-mediated ring-closure reaction

• Vaida Milišiūnaitė,
• Rūta Paulavičiūtė,
• Eglė Arbačiauskienė,
• Vytas Martynaitis,
• Wolfgang Holzer and
• Algirdas Šačkus

Beilstein J. Org. Chem. 2019, 15, 679–684, doi:10.3762/bjoc.15.62

• synthetic methods has been developed for the construction of carbon–heteroatom bonds using these types of catalysts. For example, the gold(I) catalyst [(Ph3PAu)3O]BF4 was applied in the regioselective intramolecular cyclization of alkynols to construct bicyclic ethers [37], while the silver(I) catalyst

Design of indole- and MCR-based macrocycles as p53-MDM2 antagonists

• Constantinos G. Neochoritis,
• Maryam Kazemi Miraki,
• Eman M. M. Abdelraheem,
• Ewa Surmiak,
• Tryfon Zarganes-Tzitzikas,
• Beata Łabuzek,
• Tad A. Holak and
• Alexander Dömling

Beilstein J. Org. Chem. 2019, 15, 513–520, doi:10.3762/bjoc.15.45

• physicochemical properties, their roles in biological systems and the associated synthetic challenges [6][7]. However, only few synthetic methods allow for the convergent and fast access to a large macrocyclic chemical space [8][9][10]; most of the times their synthesis is complex, multistep and sequential [11

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

• purines and 7-deazapurines. Results and Discussion We have recently observed significant fluorescence in the triazolylpurine and triazolyl-7-deazapurine series [25][29][40][41]. Therefore, we developed synthetic methods that can provide structurally related chromophores of the purine and 7-deazapurine

• phenyl rings were installed. It can be concluded that 2,6-diazidopurines are versatile intermediates for the synthesis of both the 2-amino-6-triazolylpurine and 6-amino-2-triazolylpurine derivatives. Comparison of both synthetic methods (2→4→5 versus 2→6→7/8/9) reveals that the newly developed approach