Annulation of a 1,3-dithiole ring to a sterically hindered o-quinone core. Novel ditopic redox-active ligands

• Sergey V. Norkov,
• Anton V. Cherkasov,
• Andrey S. Shavyrin,
• Maxim V. Arsenyev,
• Viacheslav A. Kuropatov and
• Vladimir K. Cherkasov

Beilstein J. Org. Chem. 2021, 17, 273–282, doi:10.3762/bjoc.17.26

• reduction with sodium dithionite in a water/methanol mixture: at these conditions o-quinone 6a converts into catechol 10. It has been shown also that the thiocarbonyl group in 6a could be easily converted into a carbonyl group by action of mercury(II) acetate in solution (Scheme 3). EPR spectroscopy studies

The preparation and properties of 1,1-difluorocyclopropane derivatives

• Kymbat S. Adekenova,
• Peter B. Wyatt and
• Sergazy M. Adekenov

Beilstein J. Org. Chem. 2021, 17, 245–272, doi:10.3762/bjoc.17.25

• Difluorocarbene methods with organometallic sources Decomposition of phenyl(trifluoromethyl)mercury in the presence of sodium iodide: The preparation of difluorocyclopropanes using phenyl(trifluoromethyl)mercury (PhHgCF3, 45, Seyferth's reagent) as a source of difluorocarbene, results in good yields of the

• (trifluoromethyl)mercury (IHgCF3) and bis(trifluoromethyl)mercury (Hg(CF3)2) [57]. However, despite good synthetic conversions having been obtained with Seyferth's reagent [58] and the general insensitivity of organomercurials to air and moisture, the presence of mercury in all of these structures is a major

Insight into functionalized-macrocycles-guided supramolecular photocatalysis

• Minzan Zuo,
• Krishnasamy Velmurugan,
• Kaiya Wang,
• Xueqi Tian and
• Xiao-Yu Hu

Beilstein J. Org. Chem. 2021, 17, 139–155, doi:10.3762/bjoc.17.15

• of 4-nitrophenol after irradiation with a mercury lamp. The Pt or Ag nanoparticles could also be achieved by the photocatalyst property of the system in the presence of ascorbic acid. The mechanism can be explained in a way where Chl-b firstly absorbs light and generates the excited state, followed

The fluorescence of a mercury probe based on osthol

• Guangyan Luo,
• Zhishu Zeng,
• Lin Zhang,
• Zhu Tao and
• Qianjun Zhang

Beilstein J. Org. Chem. 2021, 17, 22–27, doi:10.3762/bjoc.17.3

• Guangyan Luo Zhishu Zeng Lin Zhang Zhu Tao Qianjun Zhang Key Laboratory of Macrocyclic and Supramolecular Chemistry of Guizhou Province, Guizhou University, Guiyang 550025, China 10.3762/bjoc.17.3 Abstract The ability of osthol (OST) to recognize mercury ions in aqueous solution was studied using

• probe; mercury; recognition mechanism; Introduction Mercury is a dangerous heavy-metal pollutant. Inorganic mercury (Hg2+) can be transformed into methyl mercury (MeHg+) by sulfate-reducing bacteria [1][2][3]. MeHg+ can accumulate in organisms through the food chain, resulting in serious and

• irreversible nerve damage. Therefore, it is very important to develop a highly sensitive and selective method for mercury detection. At present, the detection of mercury mainly includes atomic absorption and atomic emission spectrometry [4], inductively coupled plasma mass spectrometry [5][6], and capillary

Synthesis of 4-substituted azopyridine-functionalized Ni(II)-porphyrins as molecular spin switches

• Jannis Ludwig,
• Tobias Moje,
• Fynn Röhricht and
• Rainer Herges

Beilstein J. Org. Chem. 2020, 16, 2589–2597, doi:10.3762/bjoc.16.210

• procedure of Nishimura et al. using mercury acetate in trifluoroacetic acid and anisole as radical scavenger (Scheme 5) [34]. Cleavage of the tert-butyl protection group yielded the disulfide 1g, which was reduced with catecholborane in tetrahydrofuran to give the free thiol 1h, which readily reoxidizes

Regiodivergent synthesis of functionalized pyrimidines and imidazoles through phenacyl azides in deep eutectic solvents

• Paola Vitale,
• Luciana Cicco,
• Ilaria Cellamare,
• Filippo M. Perna,
• Antonio Salomone and
• Vito Capriati

Beilstein J. Org. Chem. 2020, 16, 1915–1923, doi:10.3762/bjoc.16.158

• chloride (ChCl)/urea (1:2 mol/mol)] were prepared by heating under stirring up to 80 °C for 10–15 min the corresponding individual components until a clear solution was obtained. 1H NMR and 13C NMR spectra were recorded on a Varian Mercury 300 or on a Bruker 400 or 600 MHz spectrometer and chemical shifts

Stereoselective Biginelli-like reaction catalyzed by a chiral phosphoric acid bearing two hydroxy groups

• Xiaoyun Hu,
• Jianxin Guo,
• Cui Wang,
• Rui Zhang and
• Victor Borovkov

Beilstein J. Org. Chem. 2020, 16, 1875–1880, doi:10.3762/bjoc.16.155

• expand the applicability of this kind of catalysts to other types of asymmetric reactions, which is underway in our laboratory. Experimental Materials and general methods: 1H and 13C NMR spectra were performed on a Varian Mercury VS 300 or Bruker Avance III 400. Optical rotations were measured on a PE

Heterogeneous photocatalysis in flow chemical reactors

• Christopher G. Thomson,
• Ai-Lan Lee and
• Filipe Vilela

Beilstein J. Org. Chem. 2020, 16, 1495–1549, doi:10.3762/bjoc.16.125

An overview on disulfide-catalyzed and -cocatalyzed photoreactions

• Yeersen Patehebieke

Beilstein J. Org. Chem. 2020, 16, 1418–1435, doi:10.3762/bjoc.16.118

• hexane for 4–72 hours under irradiation from a 125 W medium-pressure mercury lamp, and 5H-furanones were obtained in moderate to good yield (44–77%, Scheme 21). Under the same reaction conditions, unsubstituted maleate esters were also nearly quantitatively converted to the corresponding fumarate esters

• disulfide-catalyzed isomerization of allyl alcohols to carbonyl compounds under high-pressure mercury lamp irradiation (λ > 300 nm) at room temperature. The yield of the reaction reached up to 91% (Scheme 23) [30]. Using the water-soluble dendrimer disulfide, the photoinduced isomerization in water was also

Recent synthesis of thietanes

• Jiaxi Xu

Beilstein J. Org. Chem. 2020, 16, 1357–1410, doi:10.3762/bjoc.16.116

• Synthesis via intramolecular photochemical [2+2] cycloadditions: In 1985, Machida’s group reported the intramolecular photo-assisted [2 + 2] cycloadditions of N-allylthiosuccinimides 327 applying 1 kW high-pressure mercury lamp irradiation under a nitrogen atmosphere, giving the highly strained tricyclic

Recent applications of porphyrins as photocatalysts in organic synthesis: batch and continuous flow approaches

• Rodrigo Costa e Silva,
• Luely Oliveira da Silva,
• Aloisio de Andrade Bartolomeu,
• Timothy John Brocksom and
• Kleber Thiago de Oliveira

Beilstein J. Org. Chem. 2020, 16, 917–955, doi:10.3762/bjoc.16.83

• scale. The scalability of these processes had been limited by the requirement for small-volume batch reactors equipped with mercury vapor discharge lamps [1]. In general, the use of batch reactors on a large-scale is hampered due to the attenuation effect of photon transport (Bouguer–Lambert–Beer law

A method to determine the correct photocatalyst concentration for photooxidation reactions conducted in continuous flow reactors

• Clemens R. Horn and
• Sylvain Gremetz

Beilstein J. Org. Chem. 2020, 16, 871–879, doi:10.3762/bjoc.16.78

• sources over mercury arcs and other light sources commonly used in industry and classical synthetic organic photochemistry. LEDs typically have much narrower emission spectra when compared to these light sources, all of which have broad emission spectra except for low-pressure sodium vapor lamps [15][16

Aldehydes as powerful initiators for photochemical transformations

• Maria A. Theodoropoulou,
• Nikolaos F. Nikitas and
• Christoforos G. Kokotos

Beilstein J. Org. Chem. 2020, 16, 833–857, doi:10.3762/bjoc.16.76

• ) as the photoinitiator for the photografting of MAA (42) onto high-density polyethylene (39) in an aqueous solution [46]. The light source was a high-pressure mercury UV lamp (2 kW), and a cooling fan was used in order to maintain ambient temperature. Acetaldehyde (36) proved to be more efficient than

• 42 in aqueous solutions [47]. For the cases where the ketones or the aldehydes were not soluble in, or miscible with water, an amount of ethanol was added. The light source employed was a UV high-pressure mercury lamp (2 kW). All aliphatic ketones tested, including acetone (4), butanone, and pentan-2

• Hanovia 450 W mercury arc [17]. If the reaction proceeded stereospecifically, cis-2-butene would have led to the formation of the oxetanes 75a and 75b, while trans-2-butene would have led to the oxetanes 75c and 75d (Scheme 19). It was suggested that the reaction proceeded through a long-lived biradical

Copper-catalyzed O-alkenylation of phosphonates

• Nuria Vázquez-Galiñanes,
• Mariña Andón-Rodríguez,
• Patricia Gómez-Roibás and
• Martín Fañanás-Mastral

Beilstein J. Org. Chem. 2020, 16, 611–615, doi:10.3762/bjoc.16.56

• counterparts has received less attention. Current methodologies for the synthesis of acyclic mixed enol phosphonates include the Perkow-type reaction between phosphonites and α-halocarbonyl compounds [11], the mercury-catalyzed addition of phosphonic acid monoesters to terminal alkynes [12][13] and multistep

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

• and 2.98(1) Å. The C–I···Cl angles are 176.8(6)°, 173.4(6)°, 176.2(6)° and 175.9(6)°. The RXB values are 0.77. These crystal package diagrams display that a bent arrangement of the XB donors are around the central halide anion. The measured bent angles of 2-I, 2-Br and 2-Cl by mercury [46] are 146.38

• applied with the SADABS program [48]. All the structures were solved by SHELXT [49] and refined by SHELXL [50] programs against |F|2 using all data following established refinement strategies [51] through olex2 [52]. Their packing diagrams were prepared by using Mercury [46]. Computational details All

Synthesis and characterization of bis(4-amino-2-bromo-6-methoxy)azobenzene derivatives

• David Martínez-López,
• Amirhossein Babalhavaeji,
• Diego Sampedro and
• G. Andrew Woolley

Beilstein J. Org. Chem. 2019, 15, 3000–3008, doi:10.3762/bjoc.15.296

• PerkinElmer Series 200 pump with a Waters 2487 Dual λ Absorbance Detector connected to an eDAQ PowerChrom 280 recorder. One-dimensional 1H and 13C NMR spectra were recorded on a Varian UnityPlus 500 MHz or Varian Mercury 400 MHz spectrometer. Chemical shifts are reported in ppm, and the signals were

Palladium-catalyzed synthesis and nucleotide pyrophosphatase inhibition of benzo[4,5]furo[3,2-b]indoles

• Hoang Huy Do,
• Saif Ullah,
• Alexander Villinger,
• Joanna Lecka,
• Jean Sévigny,
• Peter Ehlers,
• Jamshed Iqbal and
• Peter Langer

Beilstein J. Org. Chem. 2019, 15, 2830–2839, doi:10.3762/bjoc.15.276

• = 254 nm). Column chromatography was performed on Fluka silica gel 60 (0.063–0.200 mm, 70–320 mesh) on a glass column. For the cation exchange column dowex 50WX8 H+ was used. Melting points (mp) were determined by the instrument Elektrothermal. 1H and 13C NMR spectra («Mercury-300 Varian» 300 MHz with

Iodine-mediated hydration of alkynes on keto-functionalized scaffolds: mechanistic insight and the regiospecific hydration of internal alkynes

• Zachary Lee,
• Brandon R. Jones,
• Nyochembeng Nkengbeza,
• Michael Phillips,
• Kayla Valentine,
• Alexis Stewart,
• Brandon Sellers,
• Nicholas Shuber and
• Karelle S. Aiken

Beilstein J. Org. Chem. 2019, 15, 2747–2752, doi:10.3762/bjoc.15.265

• ; regiospecific hydration; Findings The Kucherov reaction is one of the most well-known approaches for the hydration of alkynes. This reaction, originally published in 1881, requires the use of mercury(II) salts in catalytic quantities [1][2]. Countless studies have shown that mercury-based compounds are

• (II) [7], silver(I) [8], and gold(I)/(III) [9][10][11][12]. While less toxic than mercury, such catalysts are still environmental hazards and tend to be costlier [13][14]. The iodine-mediated hydration described herein is a viable solution to these issues [15][16]. This metal-free method produces

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

• by Wattanakit described several approaches for the development of chiral metal electrodes for enantioselective recognition and asymmetric synthesis developed over the past decade [18]. Concurrent with pioneering works in the field of asymmetric induction in electrochemical reduction on chiral mercury

• mixture during the electroreduction of acetophenone on a mercury cathode induces optical activity in the product (alcohol 24a, Scheme 7) [29]. Additionally, pinacol (23) was also obtained via dimerization along with chiral alcohols. The same method was reinvestigated by Wang and Lu in 2013 using a silver

• , conditions B). Based on a strychnine alkaloid-induced asymmetric electroreduction, Kopilov, Kariv and Miller showed that 4- and 2-acetylpyridines (1 and 25) could be reduced to the corresponding pyridylethanols (2 and 26, respectively) in presence of a catalytic amount of the alkaloid on a mercury cathode

Experimental and computational electrochemistry of quinazolinespirohexadienone molecular switches – differential electrochromic vs photochromic behavior

• Eric W. Webb,
• Jonathan P. Moerdyk,
• Kyndra B. Sluiter,
• Benjamin J. Pollock,
• Amy L. Speelman,
• Eugene J. Lynch,
• William F. Polik and
• Jason G. Gillmore

Beilstein J. Org. Chem. 2019, 15, 2473–2485, doi:10.3762/bjoc.15.240

• chemical oxidant (benzoquinone) added to complete the reduction of the dianion to the LW isomer. NMR spectroscopy was performed on samples 5 mm NMR tubes (Wilmad) made of clear quartz (photolyzed samples) or amber pyrex (dark samples) on a Varian Mercury or Bruker AvanceIII 400 MHz NMR. 1H NMR experiments

Effect of ring size on photoisomerization properties of stiff stilbene macrocycles

• Sandra Olsson,
• Óscar Benito Pérez,
• Magnus Blom and
• Adolf Gogoll

Beilstein J. Org. Chem. 2019, 15, 2408–2418, doi:10.3762/bjoc.15.233

• system. 1H and 13C NMR spectra were recorded on Varian Mercury Plus (1H at 300.03 MHz), Agilent 400-MR DD2 (1H at 399.98 MHz, 13C at 100.58 MHz), Varian Unity Inova (1H at 499.94 MHz) and Bruker Avance Neo (1H at 500.15 MHz, 13C at 125.78 MHz) spectrometers at 25 °C. Chemical shifts (δ) are reported in

A novel three-component reaction between isocyanides, alcohols or thiols and elemental sulfur: a mild, catalyst-free approach towards O-thiocarbamates and dithiocarbamates

• András György Németh,
• György Miklós Keserű and
• Péter Ábrányi-Balogh

Beilstein J. Org. Chem. 2019, 15, 1523–1533, doi:10.3762/bjoc.15.155

• as enzyme inhibitors [26] or antitumor agents [27]. These species are also used as valuable synthetic intermediates [28] and chemosensors for mercury and silver [29][30]. The general methods for the synthesis of O-thiocarbamates and dithiocarbamates traditionally rely on substitution reactions of the

Formation of an unexpected 3,3-diphenyl-3H-indazole through a facile intramolecular [2 + 3] cycloaddition of the diazo intermediate

• Andrew T. King,
• Hugh G. Hiscocks,
• Lidia Matesic,
• Mohan Bhadbhade,
• Roger Bishop and
• Alison T. Ung

Beilstein J. Org. Chem. 2019, 15, 1347–1354, doi:10.3762/bjoc.15.134

• refinements were carried out using SHELXL-2014 [35] through Olex2 [36] suite of software. The non-hydrogen atoms were refined anisotropically. Molecular graphics were generated using Mercury [37]. Key crystallographic data and refinement details are presented in Table 1. Crystal structure data

Insertion of [1.1.1]propellane into aromatic disulfides

• Robin M. Bär,
• Gregor Heinrich,
• Martin Nieger,
• Olaf Fuhr and
• Stefan Bräse

Beilstein J. Org. Chem. 2019, 15, 1172–1180, doi:10.3762/bjoc.15.114

• , the conversion could be accelerated in the beginning of the measurement. However, after the work-up of the reaction with radical initiator, an insoluble white solid, presumably longer [n]staffanes, was discovered. When the reaction was performed in a 500 W UV reactor (medium-pressure mercury-vapor

Novel (2-amino-4-arylimidazolyl)propanoic acids and pyrrolo[1,2-c]imidazoles via the domino reactions of 2-amino-4-arylimidazoles with carbonyl and methylene active compounds

• Victoria V. Lipson,
• Tetiana L. Pavlovska,
• Nataliya V. Svetlichnaya,
• Anna A. Poryvai,
• Nikolay Yu. Gorobets,
• Erik V. Van der Eycken,
• Irina S. Konovalova,
• Svetlana V. Shiskina,
• Alexander V. Borisov,
• Vladimir I. Musatov and
• Alexander V. Mazepa

Beilstein J. Org. Chem. 2019, 15, 1032–1045, doi:10.3762/bjoc.15.101

• Specord M-82 spectrometer. The 1H NMR spectra were measured on a Varian Mercury VX-200 (200 MHz) and Bruker AM-400 spectrometer (400 MHz), 13C NMR spectra were measured on a Bruker AM-400 (100 MHz) and Bruker Avance DRX 500 (125 МHz) spectrometers in DMSO-d6, CDCl3 and trifluoroacetic acid (TFA) using TMS