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

• Engineering, Czestochowa University of Technology, Armii Krajowej 17, Czestochowa, 42-200, Poland 10.3762/bjoc.13.235 Abstract Nine new quadrupolar chromophores based on diketopyrrolopyrrole were designed and prepared by cross-coupling reactions. The property tuning has been achieved by structural variation

• -emitting diodes (OLED), fluorophores, probes for ion sensing, functional polymers, and more recently also chromophores with nonlinear optical (NLO) activity. The latter property is mostly dictated by their conjugated character, electron-accepting behavior of the DPP scaffold, strong emissive character, and

• ]. Moreover, some DPP derivatives also showed aggregation induced emission (AIE) [13][14] and the ability to selectively sense fluoride ions [26][27][28]. The modern era of DPP chromophores has been opened by Gryko et al. [3][11][12][18][20][21][29] who have demonstrated their large and tunable two-photon

One-pot syntheses of blue-luminescent 4-aryl-1H-benzo[f]isoindole-1,3(2H)-diones by T3P^® activation of 3-arylpropiolic acids

• Melanie Denißen,
• Alexander Kraus,
• Guido J. Reiss and
• Thomas J. J. Müller

Beilstein J. Org. Chem. 2017, 13, 2340–2351, doi:10.3762/bjoc.13.231

• ] where fundamental organic reactions are combined in one-pot sequences [25][26][27][28][29]. Multicomponent reactions (MCR) take advantage of creating and transforming reactive functionalities in the same reaction vessel without intermediary work-up [30]. Syntheses of functional chromophores by MCR [31

• ][32] have indeed become a powerful tool in synthetic chemistry for convergently approaching substance libraries of luminescent molecules. In particular, blue-emissive heterocyclic chromophores, intensively requested in illumination research, are equally accessible by MCR strategies [33]. Cyclic imides

• by an integrating sphere. The emission maximum appears at 468.5 nm, i.e., at the same longest wavelength band as in solution. Therefore, 1H-benzo[f]isoindole-1,3(2H)-diones 4 can be considered as AIE (aggregation induced emission) chromophores [56][57][58]. In comparison to the 1-phenyl-[2,3-c

Theoretical simulation of the infrared signature of mechanically stressed polymer solids

• Matthew S. Sammon,
• Milan Ončák and
• Martin K. Beyer

Beilstein J. Org. Chem. 2017, 13, 1710–1716, doi:10.3762/bjoc.13.165

• , especially since a large number of C–H stretching, bending and wagging modes are more or less strongly coupled [30]. In the present study, we therefore focus on molecules with strong infrared chromophores, such as C–N and C–O groups. In particular, we choose N-propylpropanamide and propyl propanoate as model

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

• street, 15, 614990, Perm, Russia Laboratory of organic semiconductors, Natural Sciences Institute, Perm State University, Genkel street, 4, 614990, Perm, Russia 10.3762/bjoc.13.158 Abstract In this paper we present a synthetic approach to six new D–π–A–D conjugated chromophores containing the N-[ω-(4

• -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

• prop-2-en-1-one fragment, while the compounds containing a 2-aminopyrimidine moiety exhibit both positive and negative solvatochromism. The fluorescence quantum yields were experimentally determined for some of the synthesized chromophores; e.g., 1-(5-arylthiophen-2-yl)ethanones quantum yields were

Correlation of surface pressure and hue of planarizable push–pull chromophores at the air/water interface

• Frederik Neuhaus,
• Fabio Zobi,
• Gerald Brezesinski,
• Marta Dal Molin,
• Stefan Matile and
• Andreas Zumbuehl

Beilstein J. Org. Chem. 2017, 13, 1099–1105, doi:10.3762/bjoc.13.109

• testing the correlation of the flipper's fluorescent signal and the membrane lateral surface pressure. Hue surface-pressure correlation The flipper mechanophore shows a flexible geometry between the two heterocyclic chromophores. These two flippers can adapt to a decreasing monolayer molecular area and

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

• as transparent monoliths in different shapes [17][18][19]. Here, we communicate our first efforts to design red, green, and blue light-emitting mesoporous materials from organic chromophores, their blending to white light-emitting silica hybrids based upon additive color mixing, and as a proof of

• index and tunable color temperature the characteristics of red emissive Nile red, blue emissive perylene, and green emissive benzofurazane have to be matched with comparable emission intensity. All three chromophores exhibit absorption in the UV–vis region with comparable molar absorption coefficients

• . Additional information on the excitation mechanism of all three chromophores was gained upon excitation with UV light and recording of emission spectra at different excitation wavelengths (Figure 8). Upon excitation at 320 nm green as well as intense red emission was found. With increasing excitation

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

• optical bandgap must be further reduced by minimizing the energetic gap in the lowest occupied molecular orbitals (LUMO) between donor and acceptor [14]. One design approach towards this end involves adding electron-withdrawing end groups to existing central core chromophores. Chen and co-workers have

Development of a continuous process for α-thio-β-chloroacrylamide synthesis with enhanced control of a cascade transformation

• Olga C. Dennehy,
• Valérie M. Y. Cacheux,
• Benjamin J. Deadman,
• Denis Lynch,
• Stuart G. Collins,
• Humphrey A. Moynihan and
• Anita R. Maguire

Beilstein J. Org. Chem. 2016, 12, 2511–2522, doi:10.3762/bjoc.12.246

• ‘other’ components observed by HPLC analysis, but removed during work-up, are overestimated by detection at 250 nm (Table 1). Such an overestimation is consistent with the presence of additional chromophores, when compared to the desired product, and would indicate that these observed components may

High performance p-type molecular electron donors for OPV applications via alkylthiophene catenation chromophore extension

• Paul B. Geraghty,
• Calvin Lee,
• Jegadesan Subbiah,
• Wallace W. H. Wong,
• James L. Banal,
• Mohammed A. Jameel,
• Trevor A. Smith and
• David J. Jones

Beilstein J. Org. Chem. 2016, 12, 2298–2314, doi:10.3762/bjoc.12.223

• chromophore (BPR), where good π–π stacking is not observed, even on extended thermal annealing. Small changes in the molecular structures lead to larger impacts on the thermal behaviour of the materials. DSC thermograms for materials indicate that short and long chromophores (BMR, BBR, and BPR) show single

• chromophores can be accessed, and thereby the thermal stability of OPV devices containing these new materials can be improved. We are currently examining BQR in printed solar cells. In all cases in our structure–property relationship studies, devices incorporating materials that exhibited a high temperature

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

• is more difficult than in the case of polymer blends due to the chromophores being tethered. For example, in a polythiophene-polyselenophene block copolymer, isothermal recrystallization of the film results in an absorption profile that perfectly matches the linear combination of the homopolymers [26

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

Practical synthetic strategies towards lipophilic 6-iodotetrahydroquinolines and -dihydroquinolines

• David R. Chisholm,
• Garr-Layy Zhou,
• Ehmke Pohl,
• Roy Valentine and
• Andrew Whiting

Beilstein J. Org. Chem. 2016, 12, 1851–1862, doi:10.3762/bjoc.12.174

• mildly red shifted (to 376 nm). This behaviour indicates that 1,4-DHQ structures of this type may function as more effective donor chromophores in dyes and fluorophores than the corresponding THQs due to improved orbital overlap between the nitrogen lone pair and the aromatic π-system by virtue of the

Synthesis and properties of fluorescent 4′-azulenyl-functionalized 2,2′:6′,2″-terpyridines

• Adrian E. Ion,
• Liliana Cristian,
• Mariana Voicescu,
• Masroor Bangesh,
• Augustin M. Madalan,
• Daniela Bala,
• Constantin Mihailciuc and
• Simona Nica

Beilstein J. Org. Chem. 2016, 12, 1812–1825, doi:10.3762/bjoc.12.171

• remarkable optical and redox properties, azulene proved to be an excellent building block for developing a large variety of materials ranging from NLO chromophores [13] to molecular switches [14][15] and liquid crystals [16] or high-conductance materials [17]. In contrast to most aromatic compounds which

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

Biradical vs singlet oxygen photogeneration in suprofen–cholesterol systems

• Fabrizio Palumbo,
• Francisco Bosca,
• Isabel M. Morera,
• Inmaculada Andreu and
• Miguel A. Miranda

Beilstein J. Org. Chem. 2016, 12, 1196–1202, doi:10.3762/bjoc.12.115

• determined in dichloromethane solutions using the same absorbance value (0.30) at 308 nm for each compound. A singlet oxygen quantum yield (ΦΔ) of 0.95 for perinaphthenone in dichloromethane was used as standard [22]. Chemical structure of the photosensitizing chromophores benzophenone (BZP) and 2

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

A journey in bioinspired supramolecular chemistry: from molecular tweezers to small molecules that target myotonic dystrophy

• Steven C. Zimmerman

Beilstein J. Org. Chem. 2016, 12, 125–138, doi:10.3762/bjoc.12.14

• ” chromophores obeying the NEP), were an obvious attempt to provide water solubility to a highly aromatic structure. In Roger Adams’ Laboratory, Craig Vanzyl, Greg Hamilton, and I were able to prepare molecular tweezer 4 and several substituted analogs, but none that were water soluble [9][10]. Fortunately, the

• interested in linkers or spacers that minimally allowed or even forced the two chromophores to stack on one another. The DNA target in which we became interested was a repeating sequence (CTG)n in the DMPK gene on chromosome 19. The sequence becomes unstable when n > 50, undergoing progressive expansion to

2-Hetaryl-1,3-tropolones based on five-membered nitrogen heterocycles: synthesis, structure and properties

• Yury A. Sayapin,
• Inna O. Tupaeva,
• Alexandra A. Kolodina,
• Eugeny A. Gusakov,
• Vitaly N. Komissarov,
• Igor V. Dorogan,
• Nadezhda I. Makarova,
• Anatoly V. Metelitsa,
• Valery V. Tkachev,
• Sergey M. Aldoshin and
• Vladimir I. Minkin

Beilstein J. Org. Chem. 2015, 11, 2179–2188, doi:10.3762/bjoc.11.236

• which has attracted much attention due to the applications in various molecular probes and luminescent materials because of the remarkable photophysical properties of the ESIPT (excited state intramolecular proton transfer) chromophores [33][34]. UV-irradiation of solutions of these compounds in

Selected synthetic strategies to cyclophanes

• Sambasivarao Kotha,
• Mukesh E. Shirbhate and
• Gopalkrushna T. Waghule

Beilstein J. Org. Chem. 2015, 11, 1274–1331, doi:10.3762/bjoc.11.142

The chemical behavior of terminally tert-butylated polyolefins

• Dagmar Klein,
• Henning Hopf,
• Peter G. Jones,
• Ina Dix and
• Ralf Hänel

Beilstein J. Org. Chem. 2015, 11, 1246–1258, doi:10.3762/bjoc.11.139

• cases the terminal double bonds survive the cycloaddition process. Photochemical behavior Although oligo- and polyene substructures are present as chromophores in, inter alia, the visual pigments [12], the carotenoid antennae of photosynthesis [13][14], and vitamins A [15] and D [16], relatively little

Chiroptical properties of 1,3-diphenylallene-anchored tetrathiafulvalene and its polymer synthesis

• Masashi Hasegawa,
• Junta Endo,
• Seiya Iwata,
• Toshiaki Shimasaki and
• Yasuhiro Mazaki

Beilstein J. Org. Chem. 2015, 11, 972–979, doi:10.3762/bjoc.11.109

• systems having strong chiroptical properties because they have great potential for use in optical devices involving polarized light [1][2][3]. Chiral response, in electronic circular dichroism (ECD) based on an exciton coupling between two adequate π-chromophores, can express a pronounced chiroptical

• effect over various optical energy regions. Therefore, embedding the chromophores into a chiral rigid framework can be a practical molecular design for ascertaining chiroptical materials [4][5][6][7]. A symmetric allene framework is one of the most reliable chiral resources that can preserve a consistent

• orientation of the chromophores [8][9]. We recently introduced 1,3-bis(tetrathiafulvalenyl)allene derivatives 1, as a new class of chiral electrochromic (EC) materials consisting of redox-active chromophores and a non-centrochiral framework (Figure 1) [10]. The intensive Cotton effect on the ECD spectra is

Discrete multiporphyrin pseudorotaxane assemblies from di- and tetravalent porphyrin building blocks

• Mirko Lohse,
• Larissa K. S. von Krbek,
• Sebastian Radunz,
• Suresh Moorthy,
• Christoph A. Schalley and
• Stefan Hecht

Beilstein J. Org. Chem. 2015, 11, 748–762, doi:10.3762/bjoc.11.85

• interactions, i.e., exciton coupling, between the two porphyrin chromophores seems to be rather weak. For mass spectrometric analysis (ESI-Q-TOF MS) of the desired pseudorotaxanes separate solutions of hosts and guests were prepared (CH2Cl2, A2/C2: 0.6 mM, A4/C4: 0.3 mM). They were mixed in the respective 1:1

Photocatalytic nucleophilic addition of alcohols to styrenes in Markovnikov and anti-Markovnikov orientation

• Martin Weiser,
• Sergej Hermann,
• Alexander Penner and
• Hans-Achim Wagenknecht

Beilstein J. Org. Chem. 2015, 11, 568–575, doi:10.3762/bjoc.11.62

• -Markovnikov-type addition of cyanide to styrene [18]. Recently, we showed by a library of different chromophores that 1-(N,N-dimethylamino)pyrene (Py) can be applied as photocatalyst for the nucleophilic addition of methanol to styrene derivatives into the Markovnikov orientation [19]. Most recently, Nicewicz

An improved procedure for the preparation of Ru(bpz)₃(PF₆)₂ via a high-yielding synthesis of 2,2’-bipyrazine

• Danielle M. Schultz,
• James W. Sawicki and
• Tehshik P. Yoon

Beilstein J. Org. Chem. 2015, 11, 61–65, doi:10.3762/bjoc.11.9

• ; palladium; photocatalysis; reductive coupling; Findings Visible light-photoredox catalysis using transition metal chromophores is rapidly becoming recognized as an important strategy in organic synthesis [1][2][3][4][5]. This approach towards reaction design enables the facile generation and exploitation

• of odd-electron intermediates such as radicals and radical ions under exceptionally mild reaction conditions. A large number of transition metal chromophores with well-characterized photophysical and electrochemical properties are known, and the influence of ligand modification on the photoredox

• properties of these complexes is well understood [6][7][8]. As a result, a variety of Ru and Ir based chromophores spanning a range of redox potentials have recently become widely utilized in the design of new photocatalytic transformations [9]. In particular, the homoleptic tris(bipyrazyl) complex 2 (Ru(bpz

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

• . The obtained results [92][93][94] stress the importance of DNA-basepair dynamics for the electronic transfer processes in DNA-stacks. The efficiency of transfer is rather more controlled by motions of chromophores involved in aromatic stacking of DNA-reporter complex than with rigid aryl-stacking