Synthesis, dynamic NMR characterization and XRD studies of novel N,N’-substituted piperazines for bioorthogonal labeling

• Constantin Mamat,
• Marc Pretze,
• Matthew Gott and
• Martin Köckerling

Beilstein J. Org. Chem. 2016, 12, 2478–2489, doi:10.3762/bjoc.12.242

• connection to the label (e.g., fluorescence dye, radionuclide) and the second is used for the introduction of a (bioorthogonal) functional group (e.g., azide, alkyne, phosphane, tetrazine) to later connect to the biomolecule via bioorthogonal ligation. Our aim was the development of novel, N,N

Thiophene-forming one-pot synthesis of three thienyl-bridged oligophenothiazines and their electronic properties

• Dominik Urselmann,
• Konstantin Deilhof,
• Bernhard Mayer and
• Thomas J. J. Müller

Beilstein J. Org. Chem. 2016, 12, 2055–2064, doi:10.3762/bjoc.12.194

• -transfer characteristics [59][60][61][62][63], as hole-transport materials [64], for applications in mesoporous organo silica hybrid materials [65], and as chromophores in dye-sensitized solar cells [66][67][68]. Furthermore, (oligo)phenothiazines in their native reduced forms display a pronounced ability

The in situ generation and reactive quench of diazonium compounds in the synthesis of azo compounds in microreactors

• Faith M. Akwi and
• Paul Watts

Beilstein J. Org. Chem. 2016, 12, 1987–2004, doi:10.3762/bjoc.12.186

• II azo dye was used as a model reaction for the study. At found optimal azo coupling reaction temperature and pH an investigation of the optimum flow rates of the reactants for the diazotization and azo coupling reactions in Little Things Factory-MS microreactors was performed. A conversion of 98

• life. Even with a number of dye degradation techniques [22] currently being employed in waste water treatment, a certain percentage of the dyestuffs is still found in water bodies. This therefore is motivation for developing better methods or techniques or processes that can be used independently or in

• conjunction with the existing techniques. Microreactor technology is one such technology that can be used in the manufacture of these dyes. If used in conjunction with existing azo dye degradation techniques the amount of waste generated can easily be managed. Hisamoto et al., for example, used ‘phase

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

• substitution at the pyrrolic phenylacetylene moieties. The later complexes are expected to be stronger electron acceptors than Zn(WS3)2, and may enable charge transfer from other conjugated polymer donors that have lower energy levels than poly(3-hexylthiophene) (P3HT). Keywords: dye; fluorine; near-IR

A flow reactor setup for photochemistry of biphasic gas/liquid reactions

• Josef Schachtner,
• Patrick Bayer and
• Axel Jacobi von Wangelin

Beilstein J. Org. Chem. 2016, 12, 1798–1811, doi:10.3762/bjoc.12.170

• standard batch reactions at 10−4–10−2 M concentrations of the dye so that large volumes of the reaction remain in the dark [9][52]. It is important to note that the magnitude of attenuation coefficients of the employed chromophores is a key difference between the recently emerging field of photocatalysis

• penetration depth in a solution of acetonitrile (Figure 2) [63]. The high surface-to-volume ratio of microreactors thus increases the relative pathway of light through the solution, speeds up the rate of reactions, and minimizes competing side reactions [11][52][64][65]. Total light absorption of dye

• optimal tubing gauge of photoreactors allows irradiation of the whole reactor width, which is determined by the Beer–Lambert law. The light intensity within the reactor is dependent on the concentration and absorption coefficient of the absorbing materials (reactor walls, dye, etc.). Generally, the used

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

• the PCE of 4% [1], some key improvements have been made in designing device structures and fabrication methods, and the PCE of the PSCs rapidly increased to >20% [2][3][4][5]. Compared to the conventional organic photovoltaics and dye-sensitized solar cells (DSSCs), PSCs benefit from a broad light

From N-vinylpyrrolidone anions to modified paraffin-like oligomers via double alkylation with 1,8-dibromooctane: access to covalent networks and oligomeric amines for dye attachment

• Daniela Obels,
• Melanie Lievenbrück and
• Helmut Ritter

Beilstein J. Org. Chem. 2016, 12, 1395–1400, doi:10.3762/bjoc.12.133

• poly(ethylene glycol) side chains. Keywords: double alkylation; modified N-vinylpyrrolidone; oligomeric anthraquinone dye; paraffin-like oligomer; radical thiol-ene click reaction; Introduction Poly(N-vinylpyrrolidone) (PVP) is established in daily life due to its high water solubility and

• present the synthesis of paraffin-like oligomers via double alkylation of N-VP with 1,8-dibromooctane. Additionally, this work focuses on the use of the free double bonds for radical crosslinking as well as thiol-ene modification for subsequent dye attachment. Results and Discussion N-Vinylpyrrolidone (1

• substituent of the attached anthraquinone moiety in 5 was replaced at elevated temperature with O-(2-aminopropyl)-O'-(2-methoxyethyl)propylene glycol (Jeffamine® M 600) yielding the branched blue-colored oligomeric dye 6. The deep blue color is a result of the presence of two amino groups in 1,4-position of

Artificial Diels–Alderase based on the transmembrane protein FhuA

• Hassan Osseili,
• Daniel F. Sauer,
• Klaus Beckerle,
• Marcus Arlt,
• Tomoki Himiyama,
• Tino Polen,
• Akira Onoda,
• Ulrich Schwaneberg,
• Takashi Hayashi and
• Jun Okuda

Beilstein J. Org. Chem. 2016, 12, 1314–1321, doi:10.3762/bjoc.12.124

• dye ThioGlo® indicated that more than 95% of the cysteine residues were conjugated for each catalyst. Renaturing of the protein was successful in the case of the terpy ligand framework (for clarity of the location of the catalyst, see Figure S1 in Supporting Information File 1). After 3 days of

Synthesis of a deuterated probe for the confocal Raman microscopy imaging of squalenoyl nanomedicines

• Eric Buchy,
• Branko Vukosavljevic,
• Maike Windbergs,
• Dunja Sobot,
• Camille Dejean,
• Simona Mura,
• Patrick Couvreur and
• Didier Desmaële

Beilstein J. Org. Chem. 2016, 12, 1127–1135, doi:10.3762/bjoc.12.109

• , the use of fluorescent probes requires the covalent binding of large dye molecules (bodipy, cyanine, rhodamine etc, ...) to the drug conjugate, thus potentially modifying its physicochemical profile as well as the in vivo fate and the pharmacological activity. A simple encapsulation of an amphiphilic

Stimuli-responsive HBPS-g-PDMAEMA and its application as nanocarrier in loading hydrophobic molecules

• Yongsheng Chen,
• Li Wang,
• Haojie Yu,
• Zain-Ul-Abdin,
• Ruoli Sun,
• Guanghui Jing,
• Rongbai Tong and
• Zheng Deng

Beilstein J. Org. Chem. 2016, 12, 939–949, doi:10.3762/bjoc.12.92

• to water is a strong evidence for the loading capacity of HBPS-g-PDMAEMA for small hydrophobic molecules. To further confirm the capability of HBPE-g-PDMAEMA aggregates to encapsulate small hydrophobic molecules, Nile red (NR), a commonly used fluorescence dye was used as a model molecule. The

Indenopyrans – synthesis and photoluminescence properties

• Andreea Petronela Diac,
• Ana-Maria Ţepeş,
• Albert Soran,
• Ion Grosu,
• Anamaria Terec,
• Jean Roncali and
• Elena Bogdan

Beilstein J. Org. Chem. 2016, 12, 825–834, doi:10.3762/bjoc.12.81

• chromophores are valuable candidates for the fabrication of OLEDs [21][22], dye lasers [23], sensors [24], dye-sensitized solar cells, fluorescent probes [25] or logic gates [26]. Recently [27], 6-CF3-2H-pyran-2-ones have been reported as potential building blocks for the preparation of novel

New synthetic strategies for xanthene-dye-appended cyclodextrins

• Milo Malanga,
• Andras Darcsi,
• Mihaly Balint,
• Gabor Benkovics,
• Tamas Sohajda and
• Szabolcs Beni

Beilstein J. Org. Chem. 2016, 12, 537–548, doi:10.3762/bjoc.12.53

• can reversibly cyclize. In this context we report a green approach for the synthesis of switchable xanthene-dye-appended cyclodextrins based on the coupling agent 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMT-MM). By using 6-monoamino-β-cyclodextrin and commercially available

• supramolecular assembly of the xanthene-dye-appended cyclodextrins were developed based on the set of data collected by the extensive NMR characterization. Keywords: DMT-MM; fluorescein; rhodamine; supramolecular assembly; Introduction Cyclodextrins (CDs) are cyclic oligosaccharides consisting of 6, 7 or 8

• of the dye because of the laborious purification process. In order to reduce cost, one approach is to perform the condensation reaction that leads to the formation of the xanthene dyes by using previously functionalized reagents [7]. This approach is difficult to generalize and does not involve a

Copper-mediated arylation with arylboronic acids: Facile and modular synthesis of triarylmethanes

• H. Surya Prakash Rao and
• A. Veera Bhadra Rao

Beilstein J. Org. Chem. 2016, 12, 496–504, doi:10.3762/bjoc.12.49

• triarylmethane motif are ubiquitous and found mainly in technologically and medicinally relevant molecules like dyes [6][7][8][9], pH indicators [10][11][12], fluorescent probes [13][14][15][16][17][18] and antibacterial drugs [19]. For example, malachite green (1) is a dye, cresol red (2) is a pH indicator and

Enabling technologies and green processes in cyclodextrin chemistry

• Giancarlo Cravotto,
• Marina Caporaso,
• Laszlo Jicsinszky and
• Katia Martina

Beilstein J. Org. Chem. 2016, 12, 278–294, doi:10.3762/bjoc.12.30

• entrance via confocal laser scanning microscopy [30]. Several types of dye moiety/CD derivatives have been suggested as "switch on" or "switch off" fluorescent chemical sensors. In these systems, the complexation with a guest molecule allows to enhance or decrease the fluorescence intensity. Two water

• in Scheme 10: CD-acryloyl derivative [60][61], β-CD/dye derivatives [31][62][63][64], CD-ionic liquid hybrids [65][66], CD-based iminosugar conjugates [67], water-soluble CD homo- and heterodimers [68][69], trimers [70][71] and oligomers [72] of α-, β- and γ-CD have all been successfully produced

Determination of formation constants and structural characterization of cyclodextrin inclusion complexes with two phenolic isomers: carvacrol and thymol

• Miriana Kfoury,
• David Landy,
• Steven Ruellan,
• Lizette Auezova,
• Hélène Greige-Gerges and
• Sophie Fourmentin

Beilstein J. Org. Chem. 2016, 12, 29–42, doi:10.3762/bjoc.12.5

• inclusion complexes were determined by an UV–visible competitive method (or spectral displacement method) using the azo dye competitor MO [34]. This method requires a previous determination of Kf values of CD/MO inclusion complexes by a direct titration method. The competitive method was applied by adding 1

Bright molecules for sensing, computing and imaging: a tale of two once-troubled cities

• A. Prasanna de Silva

Beilstein J. Org. Chem. 2015, 11, 2774–2784, doi:10.3762/bjoc.11.298

• naturally harnesses the diversity available in each of the three modules. For instance, the lumophore could be a fluorescent dye [3][24], a room temperature phosphor [25][26], or a lanthanide-based emitter [27][28]. Colleagues showed that even a quantum dot [29] would fit the bill. The receptor could be an

Smart molecules for imaging, sensing and health (SMITH)

• Bradley D. Smith

Beilstein J. Org. Chem. 2015, 11, 2540–2548, doi:10.3762/bjoc.11.274

• nanomolar dissociation constants. The rate of macrocycle threading is insensitive to the length of the appended PEG chains. But the threading kinetics are greatly affected by the steric size of the second N-substituent at each end of the squaraine dye, and an N-propyl group produces a perfect mixture of

• kinetic and thermodynamic properties. The nanomolar affinity in water is exceptionally strong for a synthetic cyclophane host molecule, and it is driven by a large favorable change in enthalpy. The two oxygen atoms on the encapsulated squaraine dye form hydrogen bonds to the four macrocycle NH residues

• bacterial cells stained with fluorescent ZnDPA probe. (left) General structure of a squaraine rotaxane dye. (right) Fluorescence image of a living mouse dosed with a squaraine rotaxane probe that selectively targets bone. Reprinted with permission from [37]. Copyright (2013) American Chemical Society. The

Continuous formation of N-chloro-N,N-dialkylamine solutions in well-mixed meso-scale flow reactors

• A. John Blacker and
• Katherine E. Jolley

Beilstein J. Org. Chem. 2015, 11, 2408–2417, doi:10.3762/bjoc.11.262

• inch ID, 3/16 inch OD) along the flow channel (Figure 2). The length of the reactor and number of static mixer inserts were adjusted to vary the residence time, thus maintaining sufficient flow rate to give effective mixing. Initial experiments using toluene and an aqueous dye were used to assess

Biocatalysis for the application of CO₂ as a chemical feedstock

• Apostolos Alissandratos and
• Christopher J. Easton

Beilstein J. Org. Chem. 2015, 11, 2370–2387, doi:10.3762/bjoc.11.259

• CODH and photosensitised with a Ru dye to catalyse the reduction of CO2 using visible light. Further to this, the reported ability of a V-dependent nitrogenase to slowly reduce CO to various small-chain hydrocarbons holds much promise for the development of enzymatic processes to further transform CO

Preparation of Pickering emulsions through interfacial adsorption by soft cyclodextrin nanogels

• Shintaro Kawano,
• Toshiyuki Kida,
• Mitsuru Akashi,
• Hirofumi Sato,
• Motohiro Shizuma and
• Daisuke Ono

Beilstein J. Org. Chem. 2015, 11, 2355–2364, doi:10.3762/bjoc.11.257

• hydrophilic DM-β-CD and lipophilic benzene parts, may be affected by their hydrophilic and lipophilic balance of the nanogels. Identification of the CD nanogel assembly at the interface Adsorption of a CD nanogel at the oil–water interface in the emulsion phase was identified using a fluorescent dye-labeling

Syntheses of 2-substituted 1-amino-4-bromoanthraquinones (bromaminic acid analogues) – precursors for dyes and drugs

• Enas M. Malik,
• Younis Baqi and
• Christa E. Müller

Beilstein J. Org. Chem. 2015, 11, 2326–2333, doi:10.3762/bjoc.11.253

• ][18][19]. AQ derivatives can also exert a variety of pharmacological activities including laxative, anti-inflammatory [20][21], antitumor [22][23], antifungal [24], antiviral [25], and blood platelet inhibitory effects [26][27][28]. Reactive Blue 2 (RB-2), a chlorotriazinyl-containing AQ dye, defined

• members of the nucleotide-activated purine P2 receptor family [34][35][36][37][38][39][40]. However, it should be mentioned that ever since the commercially available dye has been used as a tool compound in P2 receptor research, there has been some doubt about its identity and purity, both of which are

Star-shaped tetrathiafulvalene oligomers towards the construction of conducting supramolecular assembly

• Masahiko Iyoda and
• Masashi Hasegawa

Beilstein J. Org. Chem. 2015, 11, 1596–1613, doi:10.3762/bjoc.11.175

• attention of chemists and physicists on high electrical conductivity and superconductivity with high Tc temperature. Recently, however, TTF and its derivatives are frequently employed as a redox-active moiety for organic electronic devices such as field-effect-transistors (FET), dye-sensitized solar cells

New palladium–oxazoline complexes: Synthesis and evaluation of the optical properties and the catalytic power during the oxidation of textile dyes

• Rym Hassani,
• Mahjoub Jabli,
• Yakdhane Kacem,
• Jérôme Marrot,
• Damien Prim and
• Béchir Ben Hassine

Beilstein J. Org. Chem. 2015, 11, 1175–1186, doi:10.3762/bjoc.11.132

• determined. Keywords: aminoalcohols; catalysis; dye decolorization; optical properties; oxazolines; palladium complexes; Introduction Palladium complexes have been used as starting materials to prepare polymers [1], agrochemicals [2], pharmaceuticals [3], flavors and fragrances [4]. They have also been

• complete removal of Eriochrome was reached in 10 min for all samples tested. In attempts to check the efficiency of the prepared complex 9 concerning the degradation of Eriochrome Blue Black B, we have discussed the results by varying the experimental conditions (contact time, initial dye concentration

• of any catalyst. However, it was observed that the concentration of the dye declined sharply, in the presence of the system catalyst/H2O2. Indeed, 84% of the target was achieved in the presence of the prepared catalyst after only 5 min of reaction time at 22 °C whereas the dye removal does not exceed

A hybrid electron donor comprising cyclopentadithiophene and dithiafulvenyl for dye-sensitized solar cells

• Gleb Sorohhov,
• Chenyi Yi,
• Michael Grätzel,
• Silvio Decurtins and
• Shi-Xia Liu

Beilstein J. Org. Chem. 2015, 11, 1052–1059, doi:10.3762/bjoc.11.118

• HOMO–LUMO gap. In turn, the direct linkage of D and A units leads to an effective π-conjugation, thus substantially lowering the HOMO–LUMO gap. Moreover, the application in dye-sensitized solar cells was investigated, showing that the power conversion efficiency increases by the insertion of the phenyl

• unit. Keywords: donor–acceptor systems; dye-sensitized solar cells; electrochemistry; intramolecular charge transfer; Knoevenagel reaction; tetrathiafulvalene; Introduction Dye-sensitized solar cells (DSSCs) have been intensively investigated as an alternative to silicon-based solar cells [1][2][3][4

• explored [15][16][17], mainly due to the high-lying HOMO energy levels leading to a thermodynamically unfavorable dye regeneration. To overcome this problem, we recently applied a Schiff-base reaction to obtain a rigid and planar quinoxaline-fused TTF-based dye that shows an intense optical ICT absorption

A new and convenient synthetic way to 2-substituted thieno[2,3-b]indoles

• Roman A. Irgashev,
• Arseny A. Karmatsky,
• Gennady L. Rusinov and
• Valery N. Charushin

Beilstein J. Org. Chem. 2015, 11, 1000–1007, doi:10.3762/bjoc.11.112

• compounds which can be applied in organic optoelectronic materials. Indeed, we have recently reported the synthesis of novel push–pull dyes IK-1,2 based on the thieno[2,3-b]indole ring system, as a donating part of dye-sensitized solar cells [8] (Figure 1). It should be noted that thieno[2,3-b]pyrrole and

• analogues. This two-step approach provides an easy access to compounds of the family of electron-rich thieno[2,3-b]indoles, which are regarded as promising building-blocks for the development of new photo- and electrosensitive molecules, e.g., novel push–pull dyes for dye-sensitized solar cells