The role of alkyl substituents in deazaadenine-based diarylethene photoswitches

• Christopher Sarter,
• Michael Heimes and
• Andres Jäschke

Beilstein J. Org. Chem. 2016, 12, 1103–1110, doi:10.3762/bjoc.12.106

• spectrum was recorded. Reversibility measurements of deazaadenosine photoswitches with one and two methyl groups. A 60 µM solution of the compound in acetonitrile was irradiated with UV light until the (pseudo-)photostationary state was reached. After recording the UV–vis spectrum, the solution was

Separation and identification of indene–C₇₀ bisadduct isomers

• Bolong Zhang,
• Jegadesan Subbiah,
• David J. Jones and
• Wallace W. H. Wong

Beilstein J. Org. Chem. 2016, 12, 903–911, doi:10.3762/bjoc.12.88

• spectrum of the IC70BA fractions. It is widely known that the UV–vis spectrum of fullerene derivatives are highly correlated to their conjugated structures [16]. Therefore, comparison of the UV–vis spectrum of each fraction with known C70 bisadducts, for example the known 2 o’clock-B isomer of IC70BA [9

• isomers (Figure 6a). Similarly, the spectrum of fractions 4 and 9-1 matched that of the previously identified 2 o’clock-B IC70BA quite well. They all show an absorption maximum at 410 nm and a shoulder at around 478 nm (Figure 6b). Finally, fractions 10 and 11 showed a very similar UV–vis spectrum profile

• to the 12 o’clock C70 bis-malonate (Figure 6c). Thus the eight major regioisomers of IC70BA were identified. However, the remaining fractions 5–8, were also confirmed to be IC70BA isomers by mass spectrometry. Since the UV–vis spectrum of these fractions did not correlate to those of the known α

Syntheses of dibenzo[d,d']benzo[2,1-b:3,4-b']difuran derivatives and their application to organic field-effect transistors

• Minh Anh Truong and
• Koji Nakano

Beilstein J. Org. Chem. 2016, 12, 805–812, doi:10.3762/bjoc.12.79

• The UV–vis spectrum of syn-DBBDF 5 in chloroform showed the strongest absorption maximum at 324 nm, while syn-DNBDF 6 showed a red-shifted absorption spectrum with the strongest absorption maximum at 365 nm (Figure 3a and Table 1). Since syn-DNBDF 6 contains one more benzene ring at each terminal of

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

• of Flu-β-CD In Supporting Information File 1, Figure S18, the UV–vis spectra of fluorescein disodium salt and of Flu-β-CD are shown. Under acidic conditions (at pH 3), the UV–vis spectrum and the fluorescence of the free dye changes remarkably. In particular, the UV band at around 490 nm is almost

Urethane tetrathiafulvalene derivatives: synthesis, self-assembly and electrochemical properties

• Xiang Sun,
• Guoqiao Lai,
• Zhifang Li,
• Yuwen Ma,
• Xiao Yuan,
• Yongjia Shen and
• Chengyun Wang

Beilstein J. Org. Chem. 2015, 11, 2343–2349, doi:10.3762/bjoc.11.255

• UV–vis spectrum of T1 (thin film on glass) before and after iodine doping. Upon exposure to iodine vapor for 30 min in a sealed container, a new absorption band was observed at approximately 850 nm, which suggested the formation of the CT complex [27]. IR spectra of TCNQ, T1/TCNQ, and T2/TCNQ are

Photoinduced 1,2,3,4-tetrahydropyridine ring conversions

• Baiba Turovska,
• Henning Lund,
• Viesturs Lūsis,
• Anna Lielpētere,
• Edvards Liepiņš,
• Sergejs Beljakovs,
• Inguna Goba and
• Jānis Stradiņš

Beilstein J. Org. Chem. 2015, 11, 2166–2170, doi:10.3762/bjoc.11.234

• potential of excited molecules is shifted to negative values (ΔE = ~2 V) compared to their ground state [21][22][23]. For example the oxidation potential of 9,10-dihydro-10-methylacridine is +0.80 V [23], which is shifted to −3.10 V in the singlet excited state [23]. The recorded UV–vis spectrum of 1

Single-molecule conductance of a chemically modified, π-extended tetrathiafulvalene and its charge-transfer complex with F₄TCNQ

• Raúl García,
• M. Ángeles Herranz,
• Edmund Leary,
• M. Teresa González,
• Gabino Rubio Bollinger,
• Marius Bürkle,
• Linda A. Zotti,
• Yoshihiro Asai,
• Fabian Pauly,
• Juan Carlos Cuevas,
• Nicolás Agraït and
• Nazario Martín

Beilstein J. Org. Chem. 2015, 11, 1068–1078, doi:10.3762/bjoc.11.120

• formation of the CT complex by recording the UV–vis spectrum of the solution. As successive amounts of the acceptor are added to the solution of the donor, the peak at 448 nm of the neutral donor species decreases and new peaks appear between 600–900 nm that grow with the addition of more acceptor and also

Tuning of tetrathiafulvalene properties: versatile synthesis of N-arylated monopyrrolotetrathiafulvalenes via Ullmann-type coupling reactions

• Vladimir A. Azov,
• Diana Janott,
• Dirk Schlüter and
• Matthias Zeller

Beilstein J. Org. Chem. 2015, 11, 860–868, doi:10.3762/bjoc.11.96

• . Electrochemical data.a Angles (°) between the planes of the aromatic ring and neighbouring pyrrole ring in 4a,b,d,e. Supporting Information Supporting Information File 279: Experimental details, details on electrochemical characterization, 1H and 13C NMR spectra of compounds 4b,d–f, UV–vis spectrum and CV of 4b

Come-back of phenanthridine and phenanthridinium derivatives in the 21st century

• Lidija-Marija Tumir,
• Marijana Radić Stojković and
• Ivo Piantanida

Beilstein J. Org. Chem. 2014, 10, 2930–2954, doi:10.3762/bjoc.10.312

• instance, adenine derivative 15 (Figure 6) selectively recognized the complementary nucleotide (UMP) by specific change in the UV–vis spectrum of phenanthridine subunits and high affinity [75]. Molecular modelling studies proposed a structure of the 15–UMP complex stabilized by a set of intra- and

Synthesis of nanodiamond derivatives carrying amino functions and quantification by a modified Kaiser test

• Gerald Jarre,
• Steffen Heyer,
• Elisabeth Memmel,
• Thomas Meinhardt and
• Anke Krueger

Beilstein J. Org. Chem. 2014, 10, 2729–2737, doi:10.3762/bjoc.10.288

• temperatures as already reported by Sarin et al. [23]. Upon cooling, this colour vanishes almost completely (only a weak residual absorption at 570 nm is observed in the UV–vis spectrum, which has to be taken into account during the quantification). It has to be mentioned that the addition of 60% ethanol

Linear-g-hyperbranched and cyclodextrin-based amphiphilic block copolymer as a multifunctional nanocarrier

• Yamei Zhao,
• Wei Tian,
• Guang Yang and
• Xiaodong Fan

Beilstein J. Org. Chem. 2014, 10, 2696–2703, doi:10.3762/bjoc.10.284

• encapsulation between the host and guest molecule will occur when the peak intensity of the UV–vis spectrum decrease regularly after the addition of the host; meanwhile, the decreased peak intensity can also reflect the increased encapsulation ability and different encapsulation structures of the host

Synthesis and characterization of a hyper-branched water-soluble β-cyclodextrin polymer

• Francesco Trotta,
• Fabrizio Caldera,
• Roberta Cavalli,
• Andrea Mele,
• Carlo Punta,
• Lucio Melone,
• Franca Castiglione,
• Barbara Rossi,
• Monica Ferro,
• Vincenza Crupi,
• Domenico Majolino,
• Valentina Venuti and
• Dominique Scalarone

Beilstein J. Org. Chem. 2014, 10, 2586–2593, doi:10.3762/bjoc.10.271

• = β-CD/pyromellitic dianhydride molar ratio. NMR spectra of fluorescein in D2O solution (a) and in the presence of the hyper-branched β-CD polymer (b). pH range: 8.25–7.50. UV–vis spectrum of fluorescein with increasing amounts of hyper-branched β-CD polymer. pH range: 8.4–7.2. 1H NMR chemical shifts

An integrated photocatalytic/enzymatic system for the reduction of CO₂ to methanol in bioglycerol–water

• Michele Aresta,
• Angela Dibenedetto,
• Tomasz Baran,
• Antonella Angelini,
• Przemysław Łabuz and
• Wojciech Macyk

Beilstein J. Org. Chem. 2014, 10, 2556–2565, doi:10.3762/bjoc.10.267

• most likely affects the enzyme activity by inducing structural modifications. In [7] a photocatalyst was used that operates on the border of the UV–vis spectrum. As described above, the goal of this research is to work in the visible-light range, possibly using direct irradiation with solar light

• disappearance of the 521 nm band in the UV–vis spectrum, along with the appearance of the characteristic band at approximately 344 nm. The process was cyclic and the appearance–disappearance of the hydride signal followed the change in position of the UV–vis band from 521 to 344 nm and back. The spectral

Molecular recognition of AT-DNA sequences by the induced CD pattern of dibenzotetraaza[14]annulene (DBTAA)–adenine derivatives

• Marijana Radić Stojković,
• Marko Škugor,
• Łukasz Dudek,
• Jarosław Grolik,
• Julita Eilmes and
• Ivo Piantanida

Beilstein J. Org. Chem. 2014, 10, 2175–2185, doi:10.3762/bjoc.10.225

• in the UV–vis spectrum of AP3am (c = 1.0 × 10−5 mol dm−3) upon titration with poly dA–poly dT; Inset: dependence of the AP3am absorbance at λmax = 347 nm on c (poly dA–poly dT), pH 7.0, sodium cacodylate buffer, I = 0.05 mol dm−3. Induced CD bands observed for AP3, AP3am, AP6 for poly dA–poly dT and

Synthesis and optical properties of pyrrolidinyl peptide nucleic acid carrying a clicked Nile red label

• Nattawut Yotapan,
• Chayan Charoenpakdee,
• Pawinee Wathanathavorn,
• Boonsong Ditmangklo,
• Hans-Achim Wagenknecht and
• Tirayut Vilaivan

Beilstein J. Org. Chem. 2014, 10, 2166–2174, doi:10.3762/bjoc.10.224

• purification. All Nile red-labeled acpcPNAs are freely soluble in water (>1 mM), providing a bright blue solution. The UV–vis spectrum of the free propargyl Nile red label 1 in acetonitrile (Figure 2a) showed absorption and fluorescence emission maxima at 538 nm and 620 nm, with a fluorescence quantum yield

Scalable synthesis of 5,11-diethynylated indeno[1,2-b]fluorene-6,12-diones and exploration of their solid state packing

• Bradley D. Rose,
• Peter J. Santa Maria,
• Aaron G. Fix,
• Chris L. Vonnegut,
• Lev N. Zakharov,
• Sean R. Parkin and
• Michael M. Haley

Beilstein J. Org. Chem. 2014, 10, 2122–2130, doi:10.3762/bjoc.10.219

• -coupling of a variety of trialkylsilylacetylenes to either 9 or 11 were modest to very good (Table 1) but were not optimized. Optical and electronic properties. Shown in Figure 2 are the UV–vis spectrum and the cyclic voltammogram of 8c, data that are representative of all the 5,11-diethynyl-IF-diones. As

• the UV–vis spectrum (Table 3). To see if this was a computational artifact, the same calculations were performed for fluorenone and benzophenone, where it has previously been established that the S0→S1 transition corresponds to π→π* and n→π*, respectively [29][30]. The calculations correctly predict

• [1,2-b]fluorenes and related indeno[1,2-b]fluorene-6,12-diones. UV–vis spectrum (left) and cyclic voltammogram (right) of dione 8c. Kohn–Sham HOMO (left) and LUMO (right) plots of 8a. Views perpendicular to the average plane of the π stack. 1st row left to right – 8a, 8b, 8c; 2nd row – 8d, 8d, 8e; 3rd

Photorelease of phosphates: Mild methods for protecting phosphate derivatives

• Sanjeewa N. Senadheera,
• Abraham L. Yousef and
• Richard S. Givens

Beilstein J. Org. Chem. 2014, 10, 2038–2054, doi:10.3762/bjoc.10.212

• protecting groups (PPGs) for phosphates depicted as diethyl phosphate (DEP) esters. A. UV–vis spectrum of 14a (1,4-HNA DEP) in 1% aq MeCN. B. Fluorescence emission/excitation spectra of 2,6-HNA GABA (0.042 mM) in pH 7.3 TRIS buffer containing 1% MeCN. Naphthyl and quinolin-5-yl caged phosphate esters 10, 14

Five-membered ring annelation in [2.2]paracyclophanes by aldol condensation

• Henning Hopf,
• Swaminathan Vijay Narayanan and
• Peter G. Jones

Beilstein J. Org. Chem. 2014, 10, 2021–2026, doi:10.3762/bjoc.10.210

• conjugated derivatives 18 and 19 display a characteristic bright yellow color and show absorption maxima at 363 and 350 nm in the UV–vis spectrum, respectively. The unconjugated isomer 20 is a colorless solid and possesses a UV maximum at 247 nm. IR and NMR spectra (see Supporting Information File 1) support

Aryl substitution of pentacenes

• Andreas R. Waterloo,
• Anna-Chiara Sale,
• Dan Lehnherr,
• Frank Hampel and
• Rik R. Tykwinski

Beilstein J. Org. Chem. 2014, 10, 1692–1705, doi:10.3762/bjoc.10.178

• the aryl pentacenes studied here, veratrole derivative 3f shows the largest red shift (33 nm) as a film compared to its solution-state UV–vis spectrum, although the origin of change in the solid state is not understood. It is worth noting, however, that more significant red-shifted λmax-values are

Improving the reactivity of phenylacetylene macrocycles toward topochemical polymerization by side chains modification

• Simon Rondeau-Gagné,
• Jules Roméo Néabo,
• Maxime Daigle,
• Katy Cantin and
• Jean-François Morin

Beilstein J. Org. Chem. 2014, 10, 1613–1619, doi:10.3762/bjoc.10.167

• to PAM3. Scanning electron microscopy (SEM) images of PAM2 xerogel in cyclohexane (10 mg/mL). Scales are a) 1 μm and b) 0.5 μm. UV–vis spectrum of PAM2 before (black) and after (red) polymerization (PDA). Background-corrected Raman spectra of PAM2 (red) and the blue material obtained after UV

Molecular recognition of surface-immobilized carbohydrates by a synthetic lectin

• Melanie Rauschenberg,
• Eva-Corrina Fritz,
• Christian Schulz,
• Tobias Kaufmann and
• Bart Jan Ravoo

Beilstein J. Org. Chem. 2014, 10, 1354–1364, doi:10.3762/bjoc.10.138

• Information File 1). Successful incorporation of the fluorophore was also evident in the UV–vis spectrum of the precursor FITC-labeled Cys-His-Cys (see Figure S1 in the Supporting Information File 1). We note that if prepared directly by air oxidation from Cys-His-Cys, HisHis as well as FITC-HisHis consist of

On the mechanism of photocatalytic reactions with eosin Y

• Michal Majek,
• Fabiana Filace and
• Axel Jacobi von Wangelin

Beilstein J. Org. Chem. 2014, 10, 981–989, doi:10.3762/bjoc.10.97

• the prevalent pathway is likely dictated by the stability of the relevant catalytic intermediates. UV–vis spectra of the photoborylation reaction mixture (RM). Fluorescence spectra of the photoborylation reaction mixture (RM). Ex. = excitation wavelength. UV–vis spectrum of p-bromobenzenediazonium

From porphyrin benzylphosphoramidate conjugates to the catalytic hydrogenation of 5,10,15,20-tetrakis(pentafluorophenyl)porphyrin

• Marcos C. de Souza,
• Leandro F. Pedrosa,
• Géssica S. Cazagrande,
• Vitor F. Ferreira,
• Maria G. P. M. S. Neves and
• José A. S. Cavaleiro

Beilstein J. Org. Chem. 2014, 10, 628–633, doi:10.3762/bjoc.10.54

• , which are potentially biologically active. UV–vis spectrum (CHCl3) of the crude mixture obtained from the hydrogenation of 1a and 1b over 10% Pd/C and triethylamine. Main products from the hydrogenation of TPPF20 with 10% Pd/C. Comparative UV–vis spectra of isolated TPPF20, TPCF20 and TPIF20 in CHCl3

Charge-transfer interaction mediated organogels from 18β-glycyrrhetinic acid appended pyrene

• Jun Hu,
• Jindan Wu,
• Qian Wang and
• Yong Ju

Beilstein J. Org. Chem. 2013, 9, 2877–2885, doi:10.3762/bjoc.9.324

• , molar ratio, [3] = 12 mM); inset graph: UV–vis spectrum of CT gel in DMSO/water (3:1, v/v). (a) UV–vis, (b) transmittance at 700 nm, (c) fluorescence intensity at 498 nm (excitation: 365 nm) at various temperatures of CT gel (3/4 = 1:1, molar ratio) in DMSO/water (3:1, v/v), inset: fluorescence spectra

Superstructures of fluorescent cyclodextrin via click-reaction

• Arkadius Maciollek,
• Helmut Ritter and
• Rainer Beckert

Beilstein J. Org. Chem. 2013, 9, 827–831, doi:10.3762/bjoc.9.94

• , OH), 3.75–3.53 (br, 28H, CH), 2.22 (br, 3H, CH3) ppm; IR: 3301 (OH), 2923 (C-H), 1653 (C=C), 1548 (ring vibr.), 1329 (OH), 1153 (COH), 1078 (COC), 1027 (COH) cm−1; MS (MALDI–TOF) (acetonitrile/water 1:10): m/z = 1412 [M + Na]+. 1H NMR-ROESY spectrum of the modified CD 3. UV–vis spectrum of 3 (4 × 10