Reagent-controlled regiodivergent intermolecular cyclization of 2-aminobenzothiazoles with β-ketoesters and β-ketoamides

• Irwan Iskandar Roslan,
• Kian-Hong Ng,
• Gaik-Khuan Chuah and
• Stephan Jaenicke

Beilstein J. Org. Chem. 2017, 13, 2739–2750, doi:10.3762/bjoc.13.270

• -efficient protocols, we have employed transition-metal-free approaches for the one-pot synthesis of imidazo[1,2-a]pyridines and thiazolamines by coupling β-ketoesters or their derivatives, phenylacetones and phenylacetophenones, with aminopyridines [20][21] and thioureas [22]. The strategy involves in situ

Consecutive hydrazino-Ugi-azide reactions: synthesis of acylhydrazines bearing 1,5-disubstituted tetrazoles

• Angélica de Fátima S. Barreto,
• Veronica Alves dos Santos and
• Carlos Kleber Z. Andrade

Beilstein J. Org. Chem. 2017, 13, 2596–2602, doi:10.3762/bjoc.13.256

• ) allow the construction of relatively complex molecules through a one-pot synthesis. The combination of IMCRs in a consecutive or sequential fashion further extends the complexity of the molecules obtained. Herein, we report the efficient application of this approach to the synthesis of acylhydrazines

One-pot syntheses of blue-luminescent 4-aryl-1H-benzo[f]isoindole-1,3(2H)-diones by T3P^® activation of 3-arylpropiolic acids

• Melanie Denißen,
• Alexander Kraus,
• Guido J. Reiss and
• Thomas J. J. Müller

Beilstein J. Org. Chem. 2017, 13, 2340–2351, doi:10.3762/bjoc.13.231

• one-pot process. Here, we report the development of the one-pot synthesis of these title compounds by a consecutive pseudo three-component approach and the investigation of the luminescence behavior by absorption and emission spectroscopy. Results and Discussion Synthesis and structure of 4

• and non-conjugated bichromophores in a rapid fashion. Studies directed towards the one-pot synthesis of more complex polycyclic emitters are currently underway. The ORTEP-style plot of crystal structure 4b (ellipsoids are draw at the 40% probability level). The ORTEP-type plot of the crystal structure

Preparation of imidazo[1,2-a]-N-heterocyclic derivatives with gem-difluorinated side chains

• Layal Hariss,
• Kamal Bou Hadir,
• Mirvat El-Masri,
• Thierry Roisnel,
• René Grée and
• Ali Hachem

Beilstein J. Org. Chem. 2017, 13, 2115–2121, doi:10.3762/bjoc.13.208

• ); HRMS (ESI) m/z [M + Na]+: calcd. for C23H18N2OF2Na, 399.12794; found, 399.1279 (0 ppm); m/z [M + H]+: calcd. for C23H19N2OF2, 377.14599; found, 377.1454 (2 ppm); m/z [M – HF + Na]+: calcd. for C23H17N2OFNa, 379.12171; found, 379.1216 (0 ppm). One pot synthesis of (2-(1,1-difluoro-3-phenylpropyl)imidazo

• 7e by X-ray crystallography analysis. Retrosynthetic scheme for the preparation of our target molecules A. Synthesis of enones 6 with a gem-difluoroalkyl side chain. Synthesis of 7a. One-pot synthesis of 7a. Synthesis of enones 6a–e. Preparation of different imidazo[1,2-a]-N-heterocyclic derivatives

Preactivation-based chemoselective glycosylations: A powerful strategy for oligosaccharide assembly

• Weizhun Yang,
• Bo Yang,
• Sherif Ramadan and
• Xuefei Huang

Beilstein J. Org. Chem. 2017, 13, 2094–2114, doi:10.3762/bjoc.13.207

• oligosaccharides including those containing both 1,2-cis and 1,2-trans linkages, branching sequences and sulfate esters. For example, a four component preactivation-based one-pot synthesis was designed to synthesize Globo-H, an important tumor-associated carbohydrate antigen (Scheme 18) [60]. Globo-H

• ; then 96, and triethyl phosphite; (b) p-TolSCl/AgOTf, −60 °C; then 99. One-pot synthesis of Globo-H hexasaccharide 105 using building blocks 101, 102, 103 and 104. Synthesis of (a) oligosaccharides 109–113 towards (b) 30-mer galactan 115. Reagents and conditions: (a) TTBP, 4 Å MS, CH2Cl2, p-TolSCl

Main group mechanochemistry

• Agota A. Gečiauskaitė and
• Felipe García

Beilstein J. Org. Chem. 2017, 13, 2068–2077, doi:10.3762/bjoc.13.204

• ) (Cp′ = C5Me4(n-Pr)). Mechanochemical synthesis of the Ar-BIAN ligands and indium(III) complexes (top). One-pot synthesis of an indium complex (bottom). Synthesis of germanes from germanium (Ge) or germanium oxide (GeO2). Ball-milling nucleophilic substitution reactions to produce acyclic and cyclic

Difunctionalization of alkenes with iodine and tert-butyl hydroperoxide (TBHP) at room temperature for the synthesis of 1-(tert-butylperoxy)-2-iodoethanes

• Hao Wang,
• Cui Chen,
• Weibing Liu and
• Zhibo Zhu

Beilstein J. Org. Chem. 2017, 13, 2023–2027, doi:10.3762/bjoc.13.200

• , Maoming 525000, P. R. China. Fax: +86-668-2923575; Tel: +86-668-2923956 10.3762/bjoc.13.200 Abstract We developed a direct vicinal difunctionalization of alkenes with iodine and TBHP at room temperature. This iodination and peroxidation in a one-pot synthesis produces 1-(tert-butylperoxy)-2-iodoethanes

Solvent-free and room temperature synthesis of 3-arylquinolines from different anilines and styrene oxide in the presence of Al₂O₃/MeSO₃H

• Hashem Sharghi,
• Mahdi Aberi,
• Mohsen Khataminejad and
• Pezhman Shiri

Beilstein J. Org. Chem. 2017, 13, 1977–1981, doi:10.3762/bjoc.13.193

• recycled catalyst could be reused five times without any significant loss in activity (Figure 1). Conclusion In conclusion, Al2O3 and MeSO3H exhibited an excellent reactivity in the one-pot synthesis of 3-arylquinolines using anilines and styrene oxide. The methodology has the advantages of good to

• . AMA = Al2O3/methanesulfonic acid Optimization studies for the synthesis of 6,7-dimethyl-3-phenylquinoline (3a) from 3,4-dimethylaniline (1a, 1.0 mmol) with styrene oxide (2, 2.0 mmol) in open air. One-pot synthesis of 3-arylquinolines from the reaction of different anilines (1.0 mmol) with styrene

One-pot multistep mechanochemical synthesis of fluorinated pyrazolones

• Joseph L. Howard,
• William Nicholson,
• Yerbol Sagatov and
• Duncan L. Browne

Beilstein J. Org. Chem. 2017, 13, 1950–1956, doi:10.3762/bjoc.13.189

• physical form in the one-pot two-step mechanochemical procedure. Optimised conditions for the one-pot synthesis. Substrate scope of the one-pot, 2 step mechanochemical synthesis (isolated yields). a1 equiv Selectfluor used. Optimisation of pyrazolone formation. Optimisation of pyrazolone fluorination

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

• predominantly towards di-fluorinated product [102]. Multi-component reactions Multi-component reactions are one of the most powerful tools for the one pot synthesis of complex molecular structures with various functional groups [103][104][105][106][107][108]. Starting from the development of the Strecker

A novel application of 2-silylated 1,3-dithiolanes for the synthesis of aryl/hetaryl-substituted ethenes and dibenzofulvenes

• Grzegorz Mlostoń,
• Paulina Pipiak,
• Róża Hamera-Fałdyga and
• Heinz Heimgartner

Beilstein J. Org. Chem. 2017, 13, 1900–1906, doi:10.3762/bjoc.13.185

• ]. General Procedure for the one-pot synthesis of ethenes 9a–f: A hetaryl thioketone 1 (1 mmol) was dissolved in THF (2–3 mL) and the solution was cooled to 0 °C (ice bath). Then, the mixture was treated with small portions of an ethereal solution of TMS-CHN2 (2 M, 0.5 mL, 1 mmol). The reaction was complete

Oxidative dehydrogenation of C–C and C–N bonds: A convenient approach to access diverse (dihydro)heteroaromatic compounds

• Santanu Hati,
• Ulrike Holzgrabe and
• Subhabrata Sen

Beilstein J. Org. Chem. 2017, 13, 1670–1692, doi:10.3762/bjoc.13.162

• -mediated oxidative dehydrogenation. NBS-mediated oxidative dehydrogenation of tetrahydro-β-carbolines. One-pot synthesis of various methyl(hetero)arenes from o-aminobenzamide in presence of di-tert-butyl peroxide (DTBP). Oxidative dehydrogenation of 1, 4-DHPs. Synthesis of quinazolines in the presence of

• lithium carbonate at high temperature. 4-Methoxy-TEMPO-catalyzed aerobic oxidative synthesis of 2-substituted benzazoles. Plausible mechanism of the 4-methoxy-TEMPO-catalyzed transformation. One-pot synthesis of 2-arylquinazolines, catalyzed by 4-hydroxy-TEMPO. Oxidative dehydrogenation – a key step in

• -pot synthesis of substituted dihydroquinazolines 35 from a variety of o-aminobenzylamines with appropriate aldehydes and alkylnitrates. The initial condensation of substituted o-aminobenzylamines with aldehydes afforded the substituted tetrahydroquinazoline 34, which was subsequently treated with a

Development of a method for the synthesis of 2,4,5-trisubstituted oxazoles composed of carboxylic acid, amino acid, and boronic acid

• Kohei Yamada,
• Naoto Kamimura and
• Munetaka Kunishima

Beilstein J. Org. Chem. 2017, 13, 1478–1485, doi:10.3762/bjoc.13.146

• , entries 3, 9 and Table 3, entries 2, 13 and 19). Therefore, this method is suitable for the synthesis of numerous oxazoles with diverse functionalities. Our strategy for the concise synthesis of 2,4,5-trisubstituted oxazoles. Synthesis of DMPOPOP. One-pot synthesis of 5-(triazinyloxy)oxazole under

• altered. However, these reactions require strongly acidic conditions or high temperatures. Therefore, a mild method for the synthesis of diverse trisubstituted oxazoles using three commercially available compounds with a wide variety of structures is still desired. Previously, we reported a one-pot

• synthesis of oxazolone from carboxylic acids and amino acids using a dehydrative condensing reagent, 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMT-MM [19][20][21][22])[23]. Formation of 5-(triazinyloxy)oxazole is also reported to occur when an excess of DMT-MM was used. Recently

One-pot synthesis of block-copolyrotaxanes through controlled rotaxa-polymerization

• Jessica Hilschmann,
• Gerhard Wenz and
• Gergely Kali

Beilstein J. Org. Chem. 2017, 13, 1310–1315, doi:10.3762/bjoc.13.127

• length as well as statistical distribution of stopper groups along the axis. Herein, we report for the first time a simple one-pot synthesis of polyrotaxanes with control of length and sequence of the polymer axis through RAFT rotaxa-polymerization of isoprene in water. RAFT polymerization was indeed

Automating multistep flow synthesis: approach and challenges in integrating chemistry, machines and logic

• Chinmay A. Shukla and
• Amol A. Kulkarni

Beilstein J. Org. Chem. 2017, 13, 960–987, doi:10.3762/bjoc.13.97

• and so on [5][6]. The multistep synthesis may or may not involve inline separation units and also in-line analytical tools to monitor the process. The multistep synthesis where the intermediate separation or work-up is not required is conventionally termed as ‘one pot’ synthesis, which is also called

Transition-metal-free one-pot synthesis of alkynyl selenides from terminal alkynes under aerobic and sustainable conditions

• Adrián A. Heredia and
• Alicia B. Peñéñory

Beilstein J. Org. Chem. 2017, 13, 910–918, doi:10.3762/bjoc.13.92

• (Table 5). Proposed mechanism In order to assess the mechanism of the three-step one-pot synthesis of 5, the reaction between the commercial reagents 6a and 0.5 equiv of diphenyl diselenide (as analogue to the dialkyl diselenides 8 proposed as intermediates) was carried out in the presence of 1 equiv t

• oxygen atmosphere. The method is also applicable to the synthesis of functionalized heterocycles in good to excellent yields. One-pot synthesis of vinyl and alkynyl selenides. Effect of t-BuOK on the formation of n-octyl alkynyl selenide 5a. Effect of reactants concentration on alkynyl selenide formation

• . Synthesis of N-ethyl-2-(n-octylselanyl)-1H-indole (9) and 3-iodo-2-(n-octylselanyl)benzofuran (10). Control reactions and mechanistic study. Proposed mechanism for the formation of selenides 5. Proposed mechanism for the formation of indole 9. Solvent screening for the one-pot synthesis of selenide 5a.a

N-Propargylamines: versatile building blocks in the construction of thiazole cores

• S. Arshadi,
• E. Vessally,
• L. Edjlali,
• R. Hosseinzadeh-Khanmiri and
• E. Ghorbani-Kalhor

Beilstein J. Org. Chem. 2017, 13, 625–638, doi:10.3762/bjoc.13.61

• thiazole-2-thiones 3 through the thermal cyclocondensation of N-propargylamines 1 with carbon disulfide as developed by Batty and Weedon [75]. (a) One-pot synthesis of 2-benzylthiazolo[3,2-a]benzimidazoles 6 through a base-catalyzed cascade reaction of internal N-propargylamines 4 and CS2. (b) Synthesis of

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

• synthesis of the [14C]indene 176, which was next applied for the examination of the indene bioconversion network expressed in Rhodococcus sp. KY1 [79]. The [14C]1-indanone 175 was obtained in the one-pot synthesis involving the Friedel–Crafts acylation of [14C]benzene 173 with chloropropionic acid chloride

Silyl-protective groups influencing the reactivity and selectivity in glycosylations

• Mikael Bols and
• Christian Marcus Pedersen

Beilstein J. Org. Chem. 2017, 13, 93–105, doi:10.3762/bjoc.13.12

• with this, the analogue of 46 having a TIPDS group rather than a DTBS was not particularly unreactive, as it is more flexible due to the bigger ring. The Yang group used 46 in a one-pot synthesis of a trisaccharide, where they took advantage of 46 being less reactive than partially benzoylated

Synthesis of structurally diverse 3,4-dihydropyrimidin-2(1H)-ones via sequential Biginelli and Passerini reactions

• Andreas C. Boukis,
• Baptiste Monney and
• Michael A. R. Meier

Beilstein J. Org. Chem. 2017, 13, 54–62, doi:10.3762/bjoc.13.7

• indicate the formation of the respective Biginelli–Passerini product. As a proof of principle, the Biginelli and Passerini reaction were combined in a one-pot synthesis. In this experiment, the Biginelli reaction was performed with an excess of the aldehyde component (three equivalents) in a minimal amount

Multicomponent synthesis of spiropyrrolidine analogues derived from vinylindole/indazole by a 1,3-dipolar cycloaddition reaction

• Manjunatha Narayanarao,
• Lokesh Koodlur,
• Vijayakumar G. Revanasiddappa,
• Subramanya Gopal and
• Susmita Kamila

Beilstein J. Org. Chem. 2016, 12, 2893–2897, doi:10.3762/bjoc.12.288

• of biological importance [1][2]. The regio- and stereoselective construction of spiro compounds by utilizing the 1,3-dipolar cycloaddition reaction of azomethine ylides has been reported [3][4][5][6]. However, unlike the previous reports, the present method is concise and facilitates the one-pot

• synthesis of multifunctionalized spiranes. The earlier works reveal the use of different reaction conditions to prepare functionalized spiroindane, spiropyrolidine, spiropyrrolizidine and spirooxindole derivatives. Among them, the 1,3-dipolar cycloaddition based route is preferred due to multiple advantages

Orthogonal protection of saccharide polyols through solvent-free one-pot sequences based on regioselective silylations

• Serena Traboni,
• Emiliano Bedini and
• Alfonso Iadonisi

Beilstein J. Org. Chem. 2016, 12, 2748–2756, doi:10.3762/bjoc.12.271

• experimentally simple tool for the straightforward access to saccharide building-blocks useful in organic synthesis. Keywords: carbohydrates; one-pot synthesis; regioselective protection; silyl protecting group; solvent-free reaction; Introduction The application of an orthogonal set of protecting groups

Biomimetic synthesis and HPLC–ECD analysis of the isomers of dracocephins A and B

• Viktor Ilkei,
• András Spaits,
• Anita Prechl,
• Áron Szigetvári,
• Zoltán Béni,
• Miklós Dékány,
• Csaba Szántay Jr,
• Judit Müller,
• Árpád Könczöl,
• Ádám Szappanos,
• Attila Mándi,
• Sándor Antus,
• Ana Martins,
• Attila Hunyadi,
• György Tibor Balogh,
• György Kalaus (†),
• Hedvig Bölcskei,
• László Hazai and
• Tibor Kurtán

Beilstein J. Org. Chem. 2016, 12, 2523–2534, doi:10.3762/bjoc.12.247

• measured, but these compounds, along with naringenin were virtually inactive in the DPPH radical scavenging test (IC50 > 200 µg/mL), compared to the positive control quercetin (IC50 = 9.4 ± 0.6 µg/mL). Conclusion An efficient one pot synthesis of dracocephins A (2a–d) and B (3a–d) was achieved starting

Et₃B-mediated and palladium-catalyzed direct allylation of β-dicarbonyl compounds with Morita–Baylis–Hillman alcohols

• Ahlem Abidi,
• Yosra Oueslati and
• Farhat Rezgui

Beilstein J. Org. Chem. 2016, 12, 2402–2409, doi:10.3762/bjoc.12.234

• interesting synthesis of bicyclic dienones in a one-pot process involving the reaction of 2-(acetoxymethyl)cyclohex-2-enone with 1,3-dicarbonyl compounds using K2CO3 as a weak base. Later, Chamakh and Amri [38] have described a one-pot synthesis of (E)-4-alkylidene-2-cyclohexen-1-ones through a cross coupling

β-Amino functionalization of cinnamic Weinreb amides in ionic liquid

• Yi-Ning Wang,
• Guo-Xiang Sun and
• Gang Qi

Beilstein J. Org. Chem. 2016, 12, 2372–2377, doi:10.3762/bjoc.12.231

• liquid, 1-n-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ([BMIM][NTf2]). Processed without the use of metal catalysts or the need of an inert gas atmosphere, the presented process can be readily performed as a one-pot synthesis at room temperature. Moreover, the preparation has the