Dialkyl dicyanofumarates and dicyanomaleates as versatile building blocks for synthetic organic chemistry and mechanistic studies

• Grzegorz Mlostoń and
• Heinz Heimgartner

Beilstein J. Org. Chem. 2017, 13, 2235–2251, doi:10.3762/bjoc.13.221

• were achieved in reactions of alkyl cyanoacetates 2 with SOCl2 in tetrahydrofuran (THF) at reflux temperature [5][6][7][8]. Unexpectedly, the attempted preparation of the di(tert-butyl) derivative was unsuccessful. The highest yield (90%) was obtained for E-1a when 2a was oxidized with I2 in the

New electroactive asymmetrical chalcones and therefrom derived 2-amino- / 2-(1H-pyrrol-1-yl)pyrimidines, containing an N-[ω-(4-methoxyphenoxy)alkyl]carbazole fragment: synthesis, optical and electrochemical properties

• Daria G. Selivanova,
• Alexei A. Gorbunov,
• Olga A. Mayorova,
• Alexander N. Vasyanin,
• Igor V. Lunegov,
• Elena V. Shklyaeva and
• Georgii G. Abashev

Beilstein J. Org. Chem. 2017, 13, 1583–1595, doi:10.3762/bjoc.13.158

• dichloromethane (DCM), acetone (DMK), benzene, tetrahydrofuran (THF), dimethylformamide (DMF), dimethyl sulfoxide (DMSO), but are poorly soluble in hot ethanol and not soluble in hexane. On the enlargement of the conjugated system the colour of the compounds solutions in the sunlight expectedly changes from

2-Methyl-2,4-pentanediol (MPD) boosts as detergent-substitute the performance of ß-barrel hybrid catalyst for phenylacetylene polymerization

• Julia Kinzel,
• Daniel F. Sauer,
• Marco Bocola,
• Marcus Arlt,
• Tayebeh Mirzaei Garakani,
• Andreas Thiel,
• Klaus Beckerle,
• Tino Polen,
• Jun Okuda and
• Ulrich Schwaneberg

Beilstein J. Org. Chem. 2017, 13, 1498–1506, doi:10.3762/bjoc.13.148

• using the robust β-barrel protein nitrobindin. The selectivity in the polymerization of phenylacetylene was influenced with the protein as second ligand sphere [12][13]. The catalyst achieved a cis/trans ratio of 91:9 in the organic solvent tetrahydrofuran (THF) or being bound on a protein surface

• water addition). Possible fragmentation of the [Rh] catalyst is indicated. FhuA ΔCVFtev was analyzed after digestion by protease from Tobacco Etch Virus (TEV). Coupling of [Rh]-1 to the open channel protein FhuA ΔCVFtev. SDS, sodium dodecyl sulfate; THF, tetrahydrofuran. Comparison of common

An improved preparation of phorbol from croton oil

• Alberto Pagani,
• Simone Gaeta,
• Andrei I. Savchenko,
• Craig M. Williams and
• Giovanni Appendino

Beilstein J. Org. Chem. 2017, 13, 1361–1367, doi:10.3762/bjoc.13.133

• phorboids in glycerol as a dark thick oil that was subjected to liquid–liquid partition to recover phorbol from the glyceryl matrix. After considerable experimentation, we found that glycerol could be efficiently removed from a tetrahydrofuran (THF) solution of the transesterification residue by repeated

Synthesis of novel 13α-estrone derivatives by Sonogashira coupling as potential 17β-HSD1 inhibitors

• Ildikó Bacsa,
• Rebeka Jójárt,
• János Wölfling,
• Gyula Schneider,
• Bianka Edina Herman,
• Mihály Szécsi and
• Erzsébet Mernyák

Beilstein J. Org. Chem. 2017, 13, 1303–1309, doi:10.3762/bjoc.13.126

• to differ depending on the position of the iodo substituent on the sterane skeleton (Scheme 1). Couplings at C-2 could efficiently be achieved using 0.1 equiv of Pd(PPh3)4 and CuI in tetrahydrofuran (THF) or dimethylformamide (DMF) as solvent in the presence of Et3N as a base at 50 °C for 20 min in a

Exploring endoperoxides as a new entry for the synthesis of branched azasugars

• Svenja Domeyer,
• Mark Bjerregaard,
• Henrik Johansson and
• Daniel Sejer Pedersen

Beilstein J. Org. Chem. 2017, 13, 644–647, doi:10.3762/bjoc.13.63

• anticipated that the reaction conditions could be optimised to favour the desired diol product. Ring contraction of acetonide-protected endoperoxide 23 by treatment with triphenylphosphine provided ready access to tetrahydrofuran 24 in good yield [21]. Finally, treatment of endoperoxide 23 with Co(salen) gave

Studies directed toward the exploitation of vicinal diols in the synthesis of (+)-nebivolol intermediates

• Runjun Devi and
• Sajal Kumar Das

Beilstein J. Org. Chem. 2017, 13, 571–578, doi:10.3762/bjoc.13.56

• investigate other cyclization approaches towards these chroman derivatives. In 2005, Borhan and co-workers described the construction of tetrahydrofuran and tetrahydropyran structures from 1,2,n-triols via an elegant cyclization involving Lewis acid-mediated cyclization of in situ generated cyclic orthoesters

Fast and efficient synthesis of microporous polymer nanomembranes via light-induced click reaction

• Qi An,
• Youssef Hassan,
• Xiaotong Yan,
• Peter Krolla-Sidenstein,
• Tawheed Mohammed,
• Mathias Lang,
• Stefan Bräse and
• Manuel Tsotsalas

Beilstein J. Org. Chem. 2017, 13, 558–563, doi:10.3762/bjoc.13.54

• otherwise. Cyclohexane, dichloromethane and dry tetrahydrofuran (THF) were purchased from Merck Millipore; acetone was purchased from VWR Chemicals. Dry THF was degassed three times via freeze-pump-thaw prior to use. PMMA average Mw ≈120.000, PS average Mw ≈170.000, 2-hydroxy-1-[4-(2-hydroxyethoxy)phenyl]-2

Dimerization reactions of aryl selenophen-2-yl-substituted thiocarbonyl S-methanides as diradical processes: a computational study

• Michael L. McKee,
• Grzegorz Mlostoń,
• Katarzyna Urbaniak and
• Heinz Heimgartner

Beilstein J. Org. Chem. 2017, 13, 410–416, doi:10.3762/bjoc.13.44

• exchange/correlation functional [19] was used with the 6-31G(d) basis set for optimization. Single-point calculations were made at the M06-2X/6-311+G(2df,p) level with the SMD implicit solvation model [14] using the standard parameters for tetrahydrofuran. Zero-point and thermal corrections were combined

• course of the dimerization of a reactive diaryl thiocarbonyl S-methanides. Potential 1,3-dipolar electrocyclization of thiocabonyl S-methanide 8A. Computed enthalpies (free energies in parentheses) at 298 K at the SMD(tetrahydrofuran)/M06-2X/6-311+G(2df,p)//M06-2X/6-31G(d) level of theory. Stepwise

• radical dimerization of the reactive thiocarbonyl S-methanide 8. Computed enthalpies (free energies in parentheses) at 298 K at the SMD(tetrahydrofuran)/M06-2X/6-311+G(2df,p)//M06-2X/6-31G(d) level of theory. The species 12E–I are all biradical intermediates in the reaction mechanism and should be able to

A chemoselective and continuous synthesis of m-sulfamoylbenzamide analogues

• Arno Verlee,
• Thomas Heugebaert,
• Tom van der Meer,
• Pavel I. Kerchev,
• Frank Van Breusegem and
• Christian V. Stevens

Beilstein J. Org. Chem. 2017, 13, 303–312, doi:10.3762/bjoc.13.33

• LC–MS analysis. In the initial screening, tetrahydrofuran (THF) was chosen as solvent (cfinal = 100 mM), however, precipitation of the ammonium salts was unavoidable. The results of this screening did show that the use of catalysts, such as pyridine or dimethylaminopyridine (DMAP), is unnecessary in

Regiochemistry of cyclocondensation reactions in the synthesis of polyazaheterocycles

• Patrick T. Campos,
• Leticia V. Rodrigues,
• Andrei L. Belladona,
• Caroline R. Bender,
• Juliana S. Bitencurt,
• Fernanda A. Rosa,
• Davi F. Back,
• Helio G. Bonacorso,
• Nilo Zanatta,
• Clarissa P. Frizzo and
• Marcos A. P. Martins

Beilstein J. Org. Chem. 2017, 13, 257–266, doi:10.3762/bjoc.13.29

• isolated in a yield of 74%. When the reaction was repeated under reflux conditions, the time to reach conversion was reduced to 30 min and product 5 was isolated in 80% yield (Table 1). Other solvents such as ethanol, tetrahydrofuran, acetone, or ethyl acetate were also tested under reflux conditions but

• were not as efficient as acetonitrile. Generally refluxing 1 and 2 in either solvent needed longer reaction times in most cases (0.5, 3, 1, and 1 h, respectively for ethanol, tetrahydrofuran, acetone, and ethyl acetate) and throughout lower yields of 5 were obtained (54, 74, 77, and 75%, respectively

Total synthesis of a Streptococcus pneumoniae serotype 12F CPS repeating unit hexasaccharide

• Peter H. Seeberger,
• Claney L. Pereira and
• Subramanian Govindan

Beilstein J. Org. Chem. 2017, 13, 164–173, doi:10.3762/bjoc.13.19

• -dimethylformamide; EtOAc: ethyl acetate; GlcA: glucouronic acid; HPLC: high-performance liquid chromatography; Lev: levulinoyl; MALDI–TOF MS: matrix-assisted laser desorption/ionization–time of flight mass spectrometry; NAP: 2-naphthylmethyl; TBS: tert-butyldimethylsilyl; THF: tetrahydrofuran; TMSOTf

Diels–Alder reactions of myrcene using intensified continuous-flow reactors

• Christian H. Hornung,
• Miguel Á. Álvarez-Diéguez,
• Thomas M. Kohl and
• John Tsanaktsidis

Beilstein J. Org. Chem. 2017, 13, 120–126, doi:10.3762/bjoc.13.15

• tetrahydrofuran (THF), ethyl acetate (EtOAc), toluene, dichloromethane (DCM) and isopropanol (iPrOH) were obtained from Merck KGaA. All reagents and solvents were used without further purification. Reaction conversions were calculated from 1H NMR spectra, which were recorded on a Bruker AC-400 spectrometer in

Benzothiadiazole oligoene fatty acids: fluorescent dyes with large Stokes shifts

• Lukas J. Patalag and
• Daniel B. Werz

Beilstein J. Org. Chem. 2016, 12, 2739–2747, doi:10.3762/bjoc.12.270

• were distilled before use unless otherwise stated. Tetrahydrofuran (THF) and diethyl ether (Et2O) were distilled from sodium/benzophenone under an argon atmosphere. Dichloromethane (CH2Cl2) and tetrachloromethane (CCl4) were distilled from CaCl2 under an argon atmosphere. All other solvents were used

Isosorbide and dimethyl carbonate: a green match

• Fabio Aricò and
• Pietro Tundo

Beilstein J. Org. Chem. 2016, 12, 2256–2266, doi:10.3762/bjoc.12.218

• double cyclisation reaction that requires 2 equiv of base for each tetrahydrofuran formed. The reaction mechanism is quite complex (Scheme 2) since it encompasses two carboxymethylation reactions (via BAc2) followed by two intramolecular cyclisations (via BAl2). In order to avoid the use of excess base

• applications, but also by its high reactivity and peculiar molecular structure [89]. Isosorbide has an open-book V-shaped configuration formed by two cis-connected tetrahydrofuran rings with an opening angle of 120°. The four oxygen atoms incorporated in the structure are in β-position to each other [61][62

Hydroxy-functionalized hyper-cross-linked ultra-microporous organic polymers for selective CO₂ capture at room temperature

• Partha Samanta,
• Priyanshu Chandra and
• Sujit K. Ghosh

Beilstein J. Org. Chem. 2016, 12, 1981–1986, doi:10.3762/bjoc.12.185

• -(hydroxymethyl)anthracene, respectively (Figure 1). HCP-91 and HCP-94 have been synthesized by using a Friedel–Crafts alkylation reaction. The thus obtained as-synthesized compounds were washed repeatedly with dimethylformamide (DMF), methanol, water, chloroform, dichloromethane and tetrahydrofuran (THF) to

Synthesis and characterization of fluorinated azadipyrromethene complexes as acceptors for organic photovoltaics

• Forrest S. Etheridge,
• Roshan J. Fernando,
• Sandra Pejić,
• Matthias Zeller and
• Geneviève Sauvé

Beilstein J. Org. Chem. 2016, 12, 1925–1938, doi:10.3762/bjoc.12.182

• using Zn(OAc)2 to a 2-step, one pot reaction with sodium hydride in tetrahydrofuran, followed by the addition of zinc(II) chloride. Zinc(II) and BF2+ chelates were purified by silica gel column chromatography to isolate the chelates as blue solids and the identity and purity was confirmed by NMR

• solvents were used as received unless otherwise specified. Xylenes and tetrahydrofuran were distilled over sodium and benzophenone, degassed and stored under nitrogen. ADP, ADPI2, WS3, BF2(WS3), and Zn(WS3)2 were synthesized and purified according to literature procedures with minor modifications [2][5][9

• reflux condenser, L1 (100 mg, 0.146 mmol) was dissolved in anhydrous tetrahydrofuran (10 mL) under N2. To this dark blue solution, anhydrous NaH (4.00 mg, 0.161 mmol) was added and the mixture was heated to 60 °C. The solution turned to bright blue. After 24 h of heating, anhydrous ZnCl2 (11.5 mg, 0.084

Experimental and theoretical investigations on the high-electron donor character of pyrido-annelated N-heterocyclic carbenes

• Michael Nonnenmacher,
• Dominik M. Buck and
• Doris Kunz

Beilstein J. Org. Chem. 2016, 12, 1884–1896, doi:10.3762/bjoc.12.178

• mL of tetrahydrofuran was cooled to −35 °C and a solution of potassium tert-butoxide (14.9 mg, 133 μmol) in 1 mL tetraydrofuran was added. After 30 min the deep red suspension was warmed up to room temperature and stirred overnight. The solvent was removed in vacuo and the residue suspended in 7 mL

TMSBr-mediated solvent- and work-up-free synthesis of α-2-deoxyglycosides from glycals

• Mei-Yuan Hsu,
• Yi-Pei Liu,
• Sarah Lam,
• Su-Ching Lin and
• Cheng-Chung Wang

Beilstein J. Org. Chem. 2016, 12, 1758–1764, doi:10.3762/bjoc.12.164

• , dimethylformamide (DMF) (64%, Table 2, entry 2) [76], acetonitrile (ACN) [74] (44%, Table 2, entry 3), tetrahydrofuran (THF) (56%, Table 2, entry 4), and dioxane [75] (50%, Table 2, entry 5) were tested as glycosylation modulators and similar yields of 25 were obtained, but their α-selectivities dramatically

Rearrangements of organic peroxides and related processes

• Ivan A. Yaremenko,
• Vera A. Vil’,
• Dmitry V. Demchuk and
• Alexander O. Terent’ev

Beilstein J. Org. Chem. 2016, 12, 1647–1748, doi:10.3762/bjoc.12.162

Rh-Catalyzed reductive Mannich-type reaction and its application towards the synthesis of (±)-ezetimibe

• Motoyuki Isoda,
• Kazuyuki Sato,
• Yurika Kunugi,
• Satsuki Tokonishi,
• Atsushi Tarui,
• Masaaki Omote,
• Hideki Minami and
• Akira Ando

Beilstein J. Org. Chem. 2016, 12, 1608–1615, doi:10.3762/bjoc.12.157

• 0.25 mm × 15 m, carrier; He). Peak areas were calculated on a Hitachi D-2500 Chromato-Integrator. Materials Tetrahydrofuran (THF) was purchased from Kanto Chemical Co. Inc. (Tokyo, Japan) in the dehydrated form. N,N-Dimethylformamide (DMF) and dichloromethane (CH2Cl2) were distilled over CaH2 and

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

• mixture was stirred under reduced pressure overnight. In a glove box, copper(I) acetate (0.05 g, 0.40 mmol, 2.20 equiv) and dichloromethane or tetrahydrofuran (3 mL) were added. The suspension was stirred at room temperature for 5 d. a) Procedure for the reaction in dichloromethane: The suspension was

• reaction in tetrahydrofuran: The solvent was removed under reduced pressure and dichloromethane (4 mL) was added in the glove box. The suspension was filtered over a frit and the solution was concentrated by reducing the solvent in vacuo to 2 mL. Diethyl ether (4 mL) was added and the formed precipitate

Enantioselective addition of diphenyl phosphonate to ketimines derived from isatins catalyzed by binaphthyl-modified organocatalysts

• Hee Seung Jang,
• Yubin Kim and
• Dae Young Kim

Beilstein J. Org. Chem. 2016, 12, 1551–1556, doi:10.3762/bjoc.12.149

• presence of 10 mol % of catalyst III together with ketimine 1a and diphenyl phosphonate (2). We obtained excellent results in ethyl acetate (85% yield, 90% ee, Table 1, entry 3), while a slight decrease in enationselectivities was observed when dichloromethane, chloroform, tetrahydrofuran, toluene, and

Biosynthesis of oxygen and nitrogen-containing heterocycles in polyketides

• Franziska Hemmerling and
• Frank Hahn

Beilstein J. Org. Chem. 2016, 12, 1512–1550, doi:10.3762/bjoc.12.148

• tetrahydrofuran formation during biosynthesis. As the enzyme must act on biosynthetic intermediates of strongly varying size, this attributes a remarkably broad substrate tolerance to PamS. No detailed characterisation of PamS has been carried out yet. Oocydin. Homologs of trans-AT-PKS-characteristic pyran

3,6-Carbazole vs 2,7-carbazole: A comparative study of hole-transporting polymeric materials for inorganic–organic hybrid perovskite solar cells

• Wei Li,
• Munechika Otsuka,
• Takehito Kato,
• Yang Wang,
• Takehiko Mori and
• Tsuyoshi Michinobu

Beilstein J. Org. Chem. 2016, 12, 1401–1409, doi:10.3762/bjoc.12.134

• GULLIVER 1500 equipped with a pump (PU-2080 Plus), an absorbance detector (RI-2031 Plus), and two Shodex GPC KF-803 columns (8.0 mm I.D. × 300 mm L) based on a conventional calibration curve using polystyrene standards. Tetrahydrofuran (40 °C) was used as a carrier solvent at the flow rate of 1.0 mL min−1