Synthesis of 2-trifluoromethylpyrazolo[5,1-a]isoquinolines via silver triflate-catalyzed or electrophile-mediated one-pot tandem reaction

• Xiaoli Zhou,
• Meiling Liu,
• Puying Luo,
• Yingjun Lai,
• Tangtao Yang and
• Qiuping Ding

Beilstein J. Org. Chem. 2014, 10, 2286–2292, doi:10.3762/bjoc.10.238

• cores [11][14] and the synthesis of novel fluorinated heterocycles [27] with potential biological applications, herein, we describe an efficient method for the one-pot synthesis of trifluoromethylated pyrazolo[5,1-a]isoquinoline derivates via a Lewis acid (AgOTf) or an electrophile- (I2 or ICl) promoted

Solution phase synthesis of short oligoribonucleotides on a precipitative tetrapodal support

• Alejandro Gimenez Molina,
• Amit M. Jabgunde,
• Pasi Virta and
• Harri Lönnberg

Beilstein J. Org. Chem. 2014, 10, 2279–2285, doi:10.3762/bjoc.10.237

• '-GMP dime by an essentially one-pot synthesis followed by a two-step, one-flask deprotection [24]. Results and Discussion Preparation of nucleosidic building blocks The synthesis of the nucleosidic building blocks is outlined in Scheme 1. The base moiety protected 2'-O-(2-cyanoethyl)-3',5'-O-(1,1,3,3

(CF₃CO)₂O/CF₃SO₃H-mediated synthesis of 1,3-diketones from carboxylic acids and aromatic ketones

• JungKeun Kim,
• Elvira Shokova,
• Victor Tafeenko and
• Vladimir Kovalev

Beilstein J. Org. Chem. 2014, 10, 2270–2278, doi:10.3762/bjoc.10.236

• ), 28.4 (CH2), 27.5 (CH2); Anal. calcd for C18H16N2: C, 83.05; H, 6.19; N, 10.76; found: C, 82.67; H, 6.35; N, 10.37. The molecular structure of 4a. One-pot synthesis of diketone 3h from acids 1d and 1c. Scope and limitations. One-pot synthesis of pyrazoles 6. TFAA/TfOH-mediated self-acylation of ω

One-pot stereoselective synthesis of α,β-differentiated diamino esters via the sequence of aminochlorination, aziridination and intermolecular S_N2 reaction

• Yiwen Xiong,
• Ping Qian,
• Chenhui Cao,
• Haibo Mei,
• Jianlin Han,
• Guigen Li and
• Yi Pan

Beilstein J. Org. Chem. 2014, 10, 1802–1807, doi:10.3762/bjoc.10.189

• good-to-excellent chemical yields. Furthermore, this reaction gives virtually complete stereochemical outcomes, and only the anti-isomer is found for all the cases, which provides an easy access to α,β-diamino acid derivatives. Experimental General procedure for the one-pot synthesis of α,β-diamino

The chemoenzymatic synthesis of clofarabine and related 2′-deoxyfluoroarabinosyl nucleosides: the electronic and stereochemical factors determining substrate recognition by E. coli nucleoside phosphorylases

• Ilja V. Fateev,
• Konstantin V. Antonov,
• Irina D. Konstantinova,
• Tatyana I. Muravyova,
• Frank Seela,
• Roman S. Esipov,
• Anatoly I. Miroshnikov and
• Igor A. Mikhailopulo

Beilstein J. Org. Chem. 2014, 10, 1657–1669, doi:10.3762/bjoc.10.173

• demonstrated that D-ribose and 2-deoxy-D-ribose can be converted to nucleosides in the cascade one-pot synthesis under the consecutive action of three E. coli enzymes, i.e., ribokinase (RK), phosphopentomutase (PPM) and nucleoside phosphorylases [24][25][26][27] (for a recent review, see [28]). In the present

• electronic structure (natural purines vs analogues) and stereochemical features (2FAra-1P vs Ara-1P) of the studied compounds to determine the substrate recognition by E. coli nucleoside phosphorylases. Moreover, the cascade one-pot synthesis of clofarabine and related arabino-, xylo- and ribo-nucleosides (6

• and in the cascade one-pot synthesis by using E. coli ribokinase (RK), phosphopentomutase (PPM) and nucleoside phosphorylases as biocatalysts [26]. It was found that the irreversible conversion of 5-aza-7-deazaguanine (17) into its arabinoside 4b proceeds smoothly achieving 50% yield after 24 h and

Orthogonal dual thiol–chloroacetyl and thiol–ene couplings for the sequential one-pot assembly of heteroglycoclusters

• Michele Fiore,
• Gour Chand Daskhan,
• Baptiste Thomas and
• Olivier Renaudet

Beilstein J. Org. Chem. 2014, 10, 1557–1563, doi:10.3762/bjoc.10.160

• binary combinations of α-D-Man or β-D-GlcNAc, thus providing rapid access to attractive heteroglycosylated platforms for diverse biological applications. Keywords: chemoselective ligation; heteroglycocluster; multivalency; multivalent glycosystems; one-pot synthesis; Introduction Multivalent

• the one-pot synthesis of hGC 11 (linear A–B gradient: 5 to 100% B in 20 min, λ = 214 nm); (a, blue) cyclodecapeptide precursor 9; (b, red) crude mixture of intermediate product 10; (c, green) corresponds to crude mixture after TCC and TEC (11). Stepwise (Route A) and sequential one-pot (Route B

Efficient routes toward the synthesis of the D-rhamno-trisaccharide related to the A-band polysaccharide of Pseudomonas aeruginosa

• Aritra Chaudhury,
• Sajal K. Maity and
• Rina Ghosh

Beilstein J. Org. Chem. 2014, 10, 1488–1494, doi:10.3762/bjoc.10.153

• ) combination as the activating reagent. The target trisaccharide was then obtained via deprotection under the Zémplen conditions to give 10 quantitatively, as is summarized in Scheme 2. However, in the interest of time and economy of resources consumed, a one-pot synthesis is always desirable. Accordingly

An economical and safe procedure to synthesize 2-hydroxy-4-pentynoic acid: A precursor towards ‘clickable’ biodegradable polylactide

• Quanxuan Zhang,
• Hong Ren and
• Gregory L. Baker

Beilstein J. Org. Chem. 2014, 10, 1365–1371, doi:10.3762/bjoc.10.139

• the conditions indicated in Scheme 4 and Table 1, propargylic derivative 5 was obtained in quantitative yield and with high purity after optimization, and it is not necessary to further purify 5. Reflux of 5 in a 2 M aqueous solution of H2SO4 enabled the one-pot synthesis of intermediate 6 via

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

• -dideoxyneoglycoconjugates 6a and 6b. Synthesis of trivalent 3-tosylamino-2,3-dideoxyneoglycoconjugate 6c. Optimization for synthesis of 3-tosylamino-2,3-dideoxyneoglycoconjugate 4a. One-pot synthesis of α-propargyl 3-tosylamino-2,3-dideoxyglycosides 2. Scope for synthesis of 3-tosylamino-2,3-dideoxyneoglycoconjugates

Homochiral BINOL-based macrocycles with π-electron-rich, electron-withdrawing or extended spacing units as receptors for C₆₀

• Marco Caricato,
• Silvia Díez González,
• Idoia Arandia Ariño and
• Dario Pasini

Beilstein J. Org. Chem. 2014, 10, 1308–1316, doi:10.3762/bjoc.10.132

• Marco Caricato Silvia Diez Gonzalez Idoia Arandia Arino Dario Pasini Department of Chemistry, University of Pavia, Viale Taramelli 10, 27100 Pavia, Italy INSTM Research Unit, Department of Chemistry, University of Pavia, 27100 Pavia, Italy 10.3762/bjoc.10.132 Abstract The “one-pot” synthesis of

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

• cyclization towards bicyclic systems (Scheme 14) such as pyrrolo-oxazepinediones 41 and pyrrolodiazepinediones 43. The latter could be used as inhibitor for aminopeptidase P. In addition, incorporation of convertible isocyanides gave access to bicyclic compound 45 [13]. A one pot synthesis towards

• steps (Scheme 21) [73]. As an extension, they also performed the reaction sequence with bifunctional building blocks 71 and 72, in which subsequent N-Boc-deprotection of 72 provided bicyclic γ-lactam-ketopiperazines 74 (Scheme 22). Krelaus et al. described the one-pot synthesis of both γ- and δ-lactams

One-pot synthesis of cyanohydrin derivatives from alkyl bromides via incorporation of two one-carbon components by consecutive radical/ionic reactions

• Shuhei Sumino,
• Akira Fusano,
• Hiroyuki Okai,
• Takahide Fukuyama and
• Ilhyong Ryu

Beilstein J. Org. Chem. 2014, 10, 150–154, doi:10.3762/bjoc.10.12

• ). During the course of our study on borohydride-mediated radical hydroxymethylation of alkyl halides with CO, we found that cyanohydrin was obtained as a byproduct when Bu4NBH3CN was used as a radical mediator [15], which led us to investigate the one-pot synthesis of cyanohydrins based on radical

Synthesis of five- and six-membered cyclic organic peroxides: Key transformations into peroxide ring-retaining products

• Alexander O. Terent'ev,
• Dmitry A. Borisov,
• Vera A. Vil’ and
• Valery M. Dembitsky

Beilstein J. Org. Chem. 2014, 10, 34–114, doi:10.3762/bjoc.10.6

Silica: An efficient catalyst for one-pot regioselective synthesis of dithioethers

• Samir Kundu,
• Babli Roy and
• Basudeb Basu

Beilstein J. Org. Chem. 2014, 10, 26–33, doi:10.3762/bjoc.10.5

• -dithioethers. Plausible mechanisms for the regioselective formation of vicinal and 1,3-dithioethers by using dry or moistened silica gel. Optimization of one-pot sequential substitution–hydrothiolation of allylic substrate with excess benzenethiol over silica at room temperature. Regioselective one-pot

• synthesis of 1,2 and 1,3-dithioethers using dry (pre-calcined) or moistened silica gel at room temperature. Supporting Information Supporting information features FTIR, 1H NMR, 13C NMR and HRMS data for 1,2 and 1,3-dithioethers (Table 2, entries 1–19) and 1H NMR and 13C NMR spectra for compounds listed in

Efficient synthesis of dihydropyrimidinones via a three-component Biginelli-type reaction of urea, alkylaldehyde and arylaldehyde

• Haijun Qu,
• Xuejian Li,
• Fan Mo and
• Xufeng Lin

Beilstein J. Org. Chem. 2013, 9, 2846–2851, doi:10.3762/bjoc.9.320

• reaction conditions.a One-pot synthesis of dihydropyrimidinones.a Optimization of the asymmetric reaction conditions.a Supporting Information Supporting Information File 580: Experimental details and spectroscopic data. Acknowledgements This work was supported by the National Natural Foundation of China

Oxidative 3,3,3-trifluoropropylation of arylaldehydes

• Akari Ikeda,
• Masaaki Omote,
• Shiho Nomura,
• Miyuu Tanaka,
• Atsushi Tarui,
• Kazuyuki Sato and
• Akira Ando

Beilstein J. Org. Chem. 2013, 9, 2417–2421, doi:10.3762/bjoc.9.279

• found that the reaction of 1 with benzaldehyde in the presence of fluoride anions afforded an allyl alcohol, which spontaneously isomerized to phenyl 3,3,3-trifluoropropyl ketone (3a). This reaction involves a one-pot synthesis of aryl 3,3,3-trifluoropropyl ketones from the corresponding arylaldehyde

A one-pot synthesis of 3-trifluoromethyl-2-isoxazolines from trifluoromethyl aldoxime

• Raoni S. B. Gonçalves,
• Michael Dos Santos,
• Guillaume Bernadat,
• Danièle Bonnet-Delpon and
• Benoit Crousse

Beilstein J. Org. Chem. 2013, 9, 2387–2394, doi:10.3762/bjoc.9.275

• simple and efficient metal-free protocol for the oxidation of trifluoromethyl aldoxime 2 into trifluoroacetonitrile oxide 4 and a one-pot synthesis of 1 through in situ cyclization of 4 with different dipolarophiles (Scheme 1). Results and Discussion Initially, another procedure for the preparation of

One-pot sequential synthesis of isocyanates and urea derivatives via a microwave-assisted Staudinger–aza-Wittig reaction

• Diego Carnaroglio,
• Katia Martina,
• Giovanni Palmisano,
• Andrea Penoni,
• Claudia Domini and
• Giancarlo Cravotto

Beilstein J. Org. Chem. 2013, 9, 2378–2386, doi:10.3762/bjoc.9.274

• reaction was repeated in a bigger scale (80 mL) in a Parr reactor at the same pressure. Despite the good conversion (about 93%), the product purity was slightly lower than that of the MW-assisted reaction. To expand the scope of this method, a sequential one-pot synthesis from the alkyl bromide to the urea

Silica sulfuric acid: a reusable solid catalyst for one pot synthesis of densely substituted pyrrole-fused isocoumarins under solvent-free conditions

• Sudipta Pathak,
• Kamalesh Debnath and
• Animesh Pramanik

Beilstein J. Org. Chem. 2013, 9, 2344–2353, doi:10.3762/bjoc.9.269

Synthesis and characterization of novel bioactive 1,2,4-oxadiazole natural product analogs bearing the N-phenylmaleimide and N-phenylsuccinimide moieties

• Catalin V. Maftei,
• Elena Fodor,
• Peter G. Jones,
• M. Heiko Franz,
• Gerhard Kelter,
• Heiner Fiebig and
• Ion Neda

Beilstein J. Org. Chem. 2013, 9, 2202–2215, doi:10.3762/bjoc.9.259

• temperatures above 100 °C [35][36]. Microwave techniques have also been employed in the synthesis of such heterocycles. The advantage of CDI is that it activates the carboxylic acid in situ and can be used for step 1 and step 2 in DMF. Scheme 2 presents the one-pot synthesis of 4-(3-tert-butyl-1,2,4-oxadiazol

• cycloaddition route. One-pot synthesis of 4-(3-tert-butyl-1,2,4-oxadiazol-5-yl)aniline (1) by using the amidoxime route. i. 1.1 equiv CDI in DMF, 30 minutes; ii. 1.1 equiv CDI in DMF, 120 °C, 4 h. One-pot synthesis of 4-(3-tert-butyl-1,2,4-oxadiazol-5-yl)aniline (1) by using the 1,3-dipolar cycloaddition route

Gold-catalyzed glycosidation for the synthesis of trisaccharides by applying the armed–disarmed strategy

• Abhijeet K. Kayastha and
• Srinivas Hotha

Beilstein J. Org. Chem. 2013, 9, 2147–2155, doi:10.3762/bjoc.9.252

• the more acid-sensitive p-methoxybenzyl derivative 12 underwent deprotection of the p-methoxybenzyl moiety to give alcohol 13 with 88% yield. The deprotection of the p-methoxybenzyl moiety can be utilized for the one-pot synthesis of glycerol mannosides from mannosyl donor 1 and compound 12 in 67

The chemistry of isoindole natural products

• Klaus Speck and
• Thomas Magauer

Beilstein J. Org. Chem. 2013, 9, 2048–2078, doi:10.3762/bjoc.9.243

• methods. This was also exemplified by medicinal chemists from AstraZeneca in the manufacturing route to an mGluR2 positive allosteric modulator [4]. In 2012, a programmable enantioselective one-pot synthesis of isoindolines was reported by Waldmann [5]. Several other strategies were pursued for the

One-step synthesis of pyridines and dihydropyridines in a continuous flow microwave reactor

• Mark C. Bagley,
• Vincenzo Fusillo,
• Robert L. Jenkins,
• M. Caterina Lubinu and
• Christopher Mason

Beilstein J. Org. Chem. 2013, 9, 1957–1968, doi:10.3762/bjoc.9.232

• –Rahtz pyridine synthesis in batch and flow The reaction conditions, temperature and residence time were optimized in batch mode under microwave irradiation for the one pot synthesis of pyridine 2b (Scheme 3) using ethyl β-aminocrotonate (11) and a readily available ethynyl ketone, phenylpropynone 12b (R

Synthesis of enones, pyrazolines and pyrrolines with gem-difluoroalkyl side chains

• Assaad Nasr El Dine,
• Ali Khalaf,
• Danielle Grée,
• Olivier Tasseau,
• Fares Fares,
• Nada Jaber,
• Philippe Lesot,
• Ali Hachem and
• René Grée

Beilstein J. Org. Chem. 2013, 9, 1943–1948, doi:10.3762/bjoc.9.230

• used for the preparation of chemical libraries. Strategy towards the target molecules. Synthesis of enones with a gem-difluoroalkyl side chain. Synthesis of pyrazolines with a gem-difluoro side chain. One-pot synthesis of pyrazolines with a gem-difluoro side chain. Synthesis of pyrrolines with a gem

• -difluoro alkyl side chain. One-pot synthesis of pyrrolines with a gem-difluoro side chain. Pd-catalyzed coupling reactions towards chemical libraries of pyrazolines with a gem-difluoro side chain. Pd-catalyzed coupling reactions towards chemical libraries of pyrrolines with a gem-difluoro side chain

Gold(I)-catalysed one-pot synthesis of chromans using allylic alcohols and phenols

• Eloi Coutant,
• Paul C. Young,
• Graeme Barker and
• Ai-Lan Lee

Beilstein J. Org. Chem. 2013, 9, 1797–1806, doi:10.3762/bjoc.9.209