Synthesis, photophysical and electrochemical properties of pyridine, pyrazine and triazine-based (D–π–)₂A fluorescent dyes

• Keiichi Imato,
• Toshiaki Enoki,
• Koji Uenaka and
• Yousuke Ooyama

Beilstein J. Org. Chem. 2019, 15, 1712–1721, doi:10.3762/bjoc.15.167

• were prepared by Stille coupling of stannyl compound 1 [3] with 3,5-dibromopyridine, 2,6-diiodopyrazine, and 2,4-dichloro-1,3,5-triazine, respectively (Scheme 1; see Experimental section for the synthetic procedure of OUJ-2). Optical properties The photoabsorption and fluorescence spectra of OUY-2, OUK

Synthesis, enantioseparation and photophysical properties of planar-chiral pillar[5]arene derivatives bearing fluorophore fragments

• Guojuan Li,
• Chunying Fan,
• Guo Cheng,
• Wanhua Wu and
• Cheng Yang

Beilstein J. Org. Chem. 2019, 15, 1601–1611, doi:10.3762/bjoc.15.164

• triplet–triplet annihilation upconversion. Optical properties Due to the fact that the Py and DPA units are too large to enter the cavity of the pillar[5]arene, we expected that the oxygen-through-annulus rotation is blocked in P5A-DPA and P5A-Py, giving rise to two pairs of enantiomeric pillar[5]arene

Reversible end-to-end assembly of selectively functionalized gold nanorods by light-responsive arylazopyrazole–cyclodextrin interaction

• Maximilian Niehues,
• Patricia Tegeder and
• Bart Jan Ravoo

Beilstein J. Org. Chem. 2019, 15, 1407–1415, doi:10.3762/bjoc.15.140

• , shape and chemical environment giving rise to different SPR band wavelengths [6][7][8]. Especially gold nanorods (AuNR) are of interest because of their good synthetic availability and their unique optical properties. Due to their anisotropy AuNR possess a transversal SPR (TSPR) band in the visible and

Selenophene-containing heterotriacenes by a C–Se coupling/cyclization reaction

• Pierre-Olivier Schwartz,
• Sebastian Förtsch,
• Astrid Vogt,
• Elena Mena-Osteritz and
• Peter Bäuerle

Beilstein J. Org. Chem. 2019, 15, 1379–1393, doi:10.3762/bjoc.15.138

• [3,2-b]selenophene [21][22] and selenolo[3,2-b]selenophene [23], were described and represent analogues to the well-known thieno[3,2-b]thiophene [24]. Three fused selenophenes only were implemented in larger heteroacenes and analyzed towards their optical properties [25] whereupon the unsubstituted

• properties The optical properties of the four heterotriacenes were investigated by UV–vis and fluorescence spectroscopy in dichloromethane solution (Figure 6, left and Table 4). The absorption spectra in the series of DTT 1 to DSS 4 showed one main absorption band exhibiting vibronic fine structure according

• as electrolyte and the redox and optical properties of the obtained films were determined. Electropolymer P(DTT) P1 has already been reported in literature and the findings agree well with our results [46][51]. In Figure 8, exemplarily the electropolymerization of heterotriacene DST 2 (left) and

Synthesis of dipolar molecular rotors as linkers for metal-organic frameworks

• Sebastian Hamer,
• Fynn Röhricht,
• Marius Jakoby,
• Ian A. Howard,
• Xianghui Zhang,
• Christian Näther and
• Rainer Herges

Beilstein J. Org. Chem. 2019, 15, 1331–1338, doi:10.3762/bjoc.15.132

• available in gram amounts for the synthesis of MOF or SURMOF structures with promising electric and optical properties. Interactions of a pair of dipolar rotors in different orientations. The axes of the rotors are parallel at a distance of 10 Å (terminal H atoms at the ethynyl units are in a plane and at

Synthesis and fluorescent properties of N(9)-alkylated 2-amino-6-triazolylpurines and 7-deazapurines

• Andrejs Šišuļins,
• Jonas Bucevičius,
• Yu-Ting Tseng,
• Irina Novosjolova,
• Kaspars Traskovskis,
• Ērika Bizdēna,
• Huan-Tsung Chang,
• Sigitas Tumkevičius and
• Māris Turks

Beilstein J. Org. Chem. 2019, 15, 474–489, doi:10.3762/bjoc.15.41

• The optical properties of the synthesized compounds were assessed by performing absorption and fluorescence spectroscopy and fluorescence quantum yield measurements. The quantum yields were determined using a fluorescence standard of quinine sulfate in 0.1 M H2SO4 as a reference [53]. Absorption and

Bioinspired cobalt cubanes with tunable redox potentials for photocatalytic water oxidation and CO₂ reduction

• Zhishan Luo,
• Yidong Hou,
• Jinshui Zhang,
• Sibo Wang and
• Xinchen Wang

Beilstein J. Org. Chem. 2018, 14, 2331–2339, doi:10.3762/bjoc.14.208

• transparent, homogeneous and clear, indicative of their similarities in structure. Based on the above analyses and comparison with the data in literatures [54][55], it is concluded that the 1-R cubanes have been successfully fabricated. Next, to investigate the effect of different ligands on the optical

• properties of the 1-R complexes, UV–vis absorption measurements were conducted. As shown in Figure 2, three absorption bands are observed in the UV–vis spectra. The lowest energy absorption appearing as a shoulder at 645 to 660 nm, is associated with the d–d transitions involving 1A1 → 1T1 and 1A1 → 1T2 for

Tetrathiafulvalene – a redox-switchable building block to control motion in mechanically interlocked molecules

• Hendrik V. Schröder and
• Christoph A. Schalley

Beilstein J. Org. Chem. 2018, 14, 2163–2185, doi:10.3762/bjoc.14.190

• macroscopic as well as on the molecular level, even the most efficient switch is useless, if no observable output is generated which helps to detect the switching process [30]. A simple “read out” is provided by the optical properties of TTF in its different switching states. For example, UV–vis spectra of

• for applications as data storage devices [83] or molecular logic gates [84]. Besides simple molecular electrochromic switches, complex TTF-based MIMs with unique optical properties have been constructed. In 2012, rotaxane 18 with a structure similar to previously reported donor–acceptor rotaxanes was

• , DFT calculations, and UV–vis spectroscopy confirmed five different redox states (TTF/NDI, TTF●+/NDI, TTF2+/NDI, TTF/NDI●−, TTF/NDI2−) and shows interesting optical properties in each of these redox states making this type of mechanically constrained donor–acceptor complex very interesting for

Rational design of boron-dipyrromethene (BODIPY) reporter dyes for cucurbit[7]uril

• Mohammad A. Alnajjar,
• Jürgen Bartelmeß,
• Robert Hein,
• Pichandi Ashokkumar,
• Mohamed Nilam,
• Werner M. Nau,
• Knut Rurack and
• Andreas Hennig

Beilstein J. Org. Chem. 2018, 14, 1961–1971, doi:10.3762/bjoc.14.171

• specific host–guest binding of 5 to CB7 on the surface, which suggests the use of 5 for straightforward surface functionalization to create nanophotonic devices as well as for multimodal surface group quantifications, e.g., using their optical properties for fluorescence and their fluorine heteroatom for X

Recent advances on organic blue thermally activated delayed fluorescence (TADF) emitters for organic light-emitting diodes (OLEDs)

• Thanh-Tuân Bui,
• Fabrice Goubard,
• Malika Ibrahim-Ouali,
• Didier Gigmes and
• Frédéric Dumur

Beilstein J. Org. Chem. 2018, 14, 282–308, doi:10.3762/bjoc.14.18

• acceptor by carbazole moieties was examined, consisting in introducing methyl groups in the proper position of the triazine or the carbazole moieties [56]. By changing the methyl group positions, optical properties of T20–T23 were not significantly modified, contrarily to their ΔEST (see Figure 7). In fact

• donor and the 4,6-diphenylpyrimidine fragment. Due to the smaller overlap of the two wavefunctions, a weaker intramolecular charge transfer was attended, enabling to provide an emission in the blue or sky-blue region. Optical properties were evaluated in solution confirming this trend, with an emission

Halogen-containing thiazole orange analogues – new fluorogenic DNA stains

• Aleksey A. Vasilev,
• Meglena I. Kandinska,
• Stanimir S. Stoyanov,
• Stanislava B. Yordanova,
• David Sucunza,
• Juan J. Vaquero,
• Obis D. Castaño,
• Stanislav Baluschev and
• Silvia E. Angelova

Beilstein J. Org. Chem. 2017, 13, 2902–2914, doi:10.3762/bjoc.13.283

• bioanalytical methods. Higher photochemical stability was demonstrated by dye 5c and this had very low fluorescence in the free state. Computational tools were used in an attempt to explain the optical properties of the studied chromophores. The results are encouraging and warrant further investigations into

Structure–property relationships and third-order nonlinearities in diketopyrrolopyrrole based D–π–A–π–D molecules

• Jan Podlesný,
• Lenka Dokládalová,
• Oldřich Pytela,
• Adam Urbanec,
• Milan Klikar,
• Numan Almonasy,
• Tomáš Mikysek,
• Jaroslav Jedryka,
• Iwan V. Kityk and
• Filip Bureš

Beilstein J. Org. Chem. 2017, 13, 2374–2384, doi:10.3762/bjoc.13.235

• of the peripheral substituents (donor) and enlargement of the π-system. Fundamental properties of target molecules were studied by differential scanning calorimetry, electrochemistry, and absorption and emission spectra. Nonlinear optical properties were studied by measuring the third harmonic

• be the strongest electron donor within the studied series of compounds. This is in accordance with our previous observations [9][35]. Except for chromophores 3a,b, insertion of an additional acetylene linker rather extended the electrochemical HOMO–LUMO gap (series a vs b). Linear optical properties

• ). Nonlinear optical properties The third harmonic generation (THG) measurements of target chromophores 1–5 were carried out by using a 1064 nm Nd:YAG source beam. Due to the relatively high absorption of chromophores 1–5 around 355 nm, the observation of the THG was possible only in the reflected light

Synthesis and application of trifluoroethoxy-substituted phthalocyanines and subphthalocyanines

• Satoru Mori and
• Norio Shibata

Beilstein J. Org. Chem. 2017, 13, 2273–2296, doi:10.3762/bjoc.13.224

• for fluorinated polymer dyes Fluoropolymers are widely used from household products to aerospace materials because they show excellent stability, as well as non-adhesive, electrical and optical properties due to the specific properties of fluorine [24][111]. Material development studies of compounds

• pertrifluoroethoxy substitutions. Synthesis and optical properties of trifluoroethoxy-substituted subphthalocyanines Subphthalocyanines [122][123][124][125] are phthalocyanine analogues unlike phthalocyanines which are planar compounds composed of four isoindoline units, and are cone-shaped distorted molecules

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

• -methoxyphenoxy)alkyl]carbazole fragment. Such readily functionalizable heterocycle as carbazole was used as a main starting compound for their preparation. The investigation of the optical properties has shown that the positive solvatochromism is inherent to the chromophores containing an electron-withdrawing

• The optical properties of all synthesized compounds were studied with the help of UV–vis absorption and fluorescence spectroscopy of their solutions in various solvents. It has been found out that all the prepared compounds bearing 9-[ω-(4-methoxyphenoxy)alkyl]carbazole moieties are readily soluble in

• substituent at the C3 atom of the carbazole cycle: 2a,b – formyl group, 3a,b – acetyl group, 4a,b – 1-chloro-3-oxoprop-1-en-1-yl moiety and 5a,b – 5-acetylthiophen-2-yl unit. That’s why it is interesting to compare their optical properties. So, we have fulfilled the overlapping of the absorption and emission

Synthesis and metal binding properties of N-alkylcarboxyspiropyrans

• Alexis Perry and
• Christina J. Kousseff

Beilstein J. Org. Chem. 2017, 13, 1542–1550, doi:10.3762/bjoc.13.154

• with the facile elaboration of the spiropyran core, have made spiropyran–merocyanine systems a common motif in molecular switch and sensing applications [2]. In this respect, the difference in optical properties between colourless, non-fluorescent spiropyran and coloured, fluorescent merocyanine has

Glyco-gold nanoparticles: synthesis and applications

• Federica Compostella,
• Olimpia Pitirollo,
• Alessandro Silvestri and
• Laura Polito

Beilstein J. Org. Chem. 2017, 13, 1008–1021, doi:10.3762/bjoc.13.100

• presentation of saccharide moieties and to exploit the peculiar optical properties of the metallic core. In this review, we present recent advances on glyco-gold nanoparticle applications in different biological fields, highlighting the key parameters which inspire the glyco nanoparticle design. Keywords

• performing system. Gold core: optical properties AuNPs, widely employed for biomedical applications, are characterized by inert nature, resisting to air oxidation and corrosion [30]. This chemical non-reactivity and inertness make AuNPs an outstanding candidate for the development of in vitro and in vivo

• devices [31][32]. Furthermore, in vitro and in vivo short term reduced toxicity of AuNPs has been widely documented [10][33][34][35][36][37][38]. AuNPs own a number of peculiar optical properties, strongly dependent on the size and the morphology of the metallic core. When AuNP dimension is comparable to

Molecular-level architectural design using benzothiadiazole-based polymers for photovoltaic applications

• Vinila N. Viswanathan,
• Arun D. Rao,
• Upendra K. Pandey,
• Arul Varman Kesavan and
• Praveen C. Ramamurthy

Beilstein J. Org. Chem. 2017, 13, 863–873, doi:10.3762/bjoc.13.87

• levels that are lower than the threshold for air oxidation (approximately −5.2 eV) [40][41] leading to a good ambient stability. The electrochemical band gap of the polymers, P1, P2 and P3 were determined as 1.9 eV, 1.78 eV, and 1.83 eV, respectively. Next, the optical properties of the polymers were

• . Electrochemical and optical properties along with theoretical calculations. Photovoltaic properties of the devices based on polymers P1, P2 and P3. Supporting Information Supporting Information File 82: Experimental details and characterization data. Acknowledgements The authors gratefully acknowledge the

Energy down converting organic fluorophore functionalized mesoporous silica hybrids for monolith-coated light emitting diodes

• Markus Börgardts and
• Thomas J. J. Müller

Beilstein J. Org. Chem. 2017, 13, 768–778, doi:10.3762/bjoc.13.76

• furnishing optima of their solid-state fluorescence quantum yields Φf (Figure 4). The optical properties of the dye-functionalized hybrid materials differ slightly from the properties of their precursor molecules in solution. For all hybrid materials a broad band can be observed in the spectra, which can be

• hybrid materials in comparison to the precursor molecule 8 was previously reported and extensively discussed [24]. Also for perylene-functionalized hybrids a peculiar influence on the optical properties by incorporation into a silica matrix was found. Most striking is the change of the vibrational fine

Fluorescent carbon dots from mono- and polysaccharides: synthesis, properties and applications

• Stephen Hill and
• M. Carmen Galan

Beilstein J. Org. Chem. 2017, 13, 675–693, doi:10.3762/bjoc.13.67

• relevant molecules have become very useful for drug delivery, sensing and catalysis to name just a few applications. As a result, nanomaterials exhibiting novel electronic and optical properties, having controlled size, geometry, surface distribution and functionality have been developed as materials for

Synthesis and optical properties of new 5'-aryl-substituted 2,5-bis(3-decyl-2,2'-bithiophen-5-yl)-1,3,4-oxadiazoles

• Anastasia S. Kostyuchenko,
• Tatyana Yu. Zheleznova,
• Anton J. Stasyuk,
• Aleksandra Kurowska,
• Wojciech Domagala,
• Adam Pron and
• Alexander S. Fisyuk

Beilstein J. Org. Chem. 2017, 13, 313–322, doi:10.3762/bjoc.13.34

Interactions between photoacidic 3-hydroxynaphtho[1,2-b]quinolizinium and cucurbit[7]uril: Influence on acidity in the ground and excited state

• Jonas Becher,
• Daria V. Berdnikova,
• Darinka Dzubiel,
• Heiko Ihmels and
• Phil M. Pithan

Beilstein J. Org. Chem. 2017, 13, 203–212, doi:10.3762/bjoc.13.23

• ]quinolizinium was synthesized by cyclodehydration route and its optical properties in different media were investigated. The absorption and emission spectra of this compound depend on the pH of the solution. Thus, at higher pH values the deprotonation yields a merocyanine-type dye that exhibits significantly

• ] hosts with high affinity [6]. In most cases, this complexation strongly affects the chemical or physical properties of the ligand. For example, it was demonstrated that the optical properties of organic dyes may be modified drastically upon complexation in the CB cavity [7]. At the same time, this

A postsynthetically 2’-“clickable” uridine with arabino configuration and its application for fluorescent labeling and imaging of DNA

• Heidi-Kristin Walter,
• Bettina Olshausen,
• Ute Schepers and
• Hans-Achim Wagenknecht

Beilstein J. Org. Chem. 2017, 13, 127–137, doi:10.3762/bjoc.13.16

• show a unique combination of optical properties [25], including suitable brightness and fluorescence quantum yields, large Stokes’ shifts compared to conventionally applied Cy3 and Cy5, and most importantly, excellent photostabilities. D1–D4 were representatively chosen since they will serve as energy

• optical properties (UV–vis absorption and fluorescence, see Supporting Information File 1), fluorescence quantum yields ΦF and melting temperatures Tm (Table 1). The reference duplexes of DNA1a and DNA1r annealed with the unmodified complementary strand showed Tm values of 61.0 °C and 62.0 °C

• contrast C and the fluorescence quantum yield ΦF. This screening revealed that the combination of donor and acceptor dyes does not necessarily yield better optical properties if they are both linked to the arabino-configured nucleoside 2 (compared to the linkage to the ribo-configured nucleoside 1

Effects of solvent additive on “s-shaped” curves in solution-processed small molecule solar cells

• John A. Love,
• Shu-Hua Chou,
• Ye Huang,
• Guilllermo C. Bazan and
• Thuc-Quyen Nguyen

Beilstein J. Org. Chem. 2016, 12, 2543–2555, doi:10.3762/bjoc.12.249

• counterparts [5][6]. Also of import stands the fact that easily modified, modular structures lead to finely-tunable energy levels and optical properties through molecular design [7][8]. Most high-performing small molecule electron-donor materials are configured such that the conjugated backbone consists of

Sydnone C-4 heteroarylation with an indolizine ring via Chichibabin indolizine synthesis

• Florin Albota,
• Mino R. Caira,
• Constantin Draghici,
• Florea Dumitrascu and
• Denisa E. Dumitrescu

Beilstein J. Org. Chem. 2016, 12, 2503–2510, doi:10.3762/bjoc.12.245

• its derivatives exhibit remarkable biological activities and optical properties. Indolizine is a privileged structure for the design of new drugs and its framework is present in many natural compounds. As a consequence, the synthesis, chemical, physicochemical and biological properties of indolizines

Comparing blends and blocks: Synthesis of partially fluorinated diblock polythiophene copolymers to investigate the thermal stability of optical and morphological properties

• Pierre Boufflet,
• Sebastian Wood,
• Jessica Wade,
• Zhuping Fei,
• Ji-Seon Kim and
• Martin Heeney

Beilstein J. Org. Chem. 2016, 12, 2150–2163, doi:10.3762/bjoc.12.205

• that of P3OT (4.70 eV) measured by the same technique [42], while the 1:4 copolymer had an IP of 5.03 eV, which is within experimental error (±0.05 eV) of the IP of F-P3OT (4.99 eV) [42]. To investigate the influence of the block compositions on the optical properties, the UV–visible absorption spectra