Solution processable diketopyrrolopyrrole (DPP) cored small molecules with BODIPY end groups as novel donors for organic solar cells

• Diego Cortizo-Lacalle,
• Calvyn T. Howells,
• Upendra K. Pandey,
• Joseph Cameron,
• Neil J. Findlay,
• Anto Regis Inigo,
• Tell Tuttle,
• Peter J. Skabara and
• Ifor D. W. Samuel

Beilstein J. Org. Chem. 2014, 10, 2683–2695, doi:10.3762/bjoc.10.283

• films from a 20 mg mL−1 solution, respectively. Film thicknesses were measured using a Dektak 150 M stylus profiler. Absorption and emission spectra of compounds 9 and 10 were obtained with a Varian Cary 300 UV–visible spectrophotometer and a Photoluminescence Quantum Yield (PLQY) measurement system

The effect of permodified cyclodextrins encapsulation on the photophysical properties of a polyfluorene with randomly distributed electron-donor and rotaxane electron-acceptor units

• Aurica Farcas,
• Ana-Maria Resmerita,
• Pierre-Henri Aubert,
• Flavian Farcas,
• Iuliana Stoica and
• Anton Airinei

Beilstein J. Org. Chem. 2014, 10, 2145–2156, doi:10.3762/bjoc.10.222

• Edinburgh FLS 980 photoluminescence spectrometer with 1 cm quartz cells. A 375 nm pulsed diode laser (EPL-375, maximum average power: 5 mW, pulse width: 73.2 ps) was used as a light source. Decay data analysis was performed by the deconvolution procedure with multiexponential decay models. The quality of

Synthesis of new, highly luminescent bis(2,2’-bithiophen-5-yl) substituted 1,3,4-oxadiazole, 1,3,4-thiadiazole and 1,2,4-triazole

• Anastasia S. Kostyuchenko,
• Vyacheslav L.Yurpalov,
• Aleksandra Kurowska,
• Wojciech Domagala,
• Adam Pron and
• Alexander S. Fisyuk

Beilstein J. Org. Chem. 2014, 10, 1596–1602, doi:10.3762/bjoc.10.165

• synthesis, efficient ring closure reaction affording a 4H-1,2,4-triazole unit is presented. All target ambipolar compounds display strong photoluminescence with measured quantum yields up to 0.59. Modification of the demonstrated synthetic routes may be exploited for the preparation of longer, specifically

• with the thiadiazole central unit. Such a decrease of the absorption band energy is typical of all sulfur containing five membered heterocycles [14][15][34]. Upon excitation with the UV light, all investigated compounds feature strong photoluminescence, emitting blue and green light (Table 2). Their

• photoluminescence quantum yields are indicated together with the formulae of the corresponding compounds. In the case of 18 (4-phenyl-4H-1,2,4-triazole ring) the photoluminescence quantum yield is almost three times higher than that measured for 15 (1,3,4-thiadiazole ring). The obtained results clearly demonstrate

First synthesis of meso-substituted pyrrolo[1,2-a]quinoxalinoporphyrins

• Dileep Kumar Singh and
• Mahendra Nath

Beilstein J. Org. Chem. 2014, 10, 808–813, doi:10.3762/bjoc.10.76

• ][12][13], organic light emitting diodes [14][15], near infrared dyes [16][17][18], hybrid solar cells [19][20][21][22], and biosensors [23][24][25] due to their intense optical absorptions and photoluminescence characteristics. On the other hand, compounds containing a pyrrolo[1,2-a]quinoxaline

Studies on the photodegradation of red, green and blue phosphorescent OLED emitters

• Susanna Schmidbauer,
• Andreas Hohenleutner and
• Burkhard König

Beilstein J. Org. Chem. 2013, 9, 2088–2096, doi:10.3762/bjoc.9.245

• emitting Ir(F,CN-ppy)3 with its higher emission energy, a participation of this mechanism is likely. However, it was shown that iridium complexes exhibit singlet oxygen quantum efficiencies close to the photoluminescence quantum efficiencies of these compounds. Djurovich et al. suggested that back-electron

Molecular assembly of amino acid interlinked, topologically symmetric, π-complementary donor–acceptor–donor triads

• M. B. Avinash,
• K. V. Sandeepa and
• T. Govindaraju

Beilstein J. Org. Chem. 2013, 9, 1565–1571, doi:10.3762/bjoc.9.178

• details, synthesis procedures, FESEM images, absorption, photoluminescence, PXRD and 2D NOESY spectra. Acknowledgements Authors thank Prof. C. N. R. Rao, FRS for constant support and encouragement; JNCASR, DST, IYBA-DBT and the government of India for financial support; Prof. G. U. Kulkarni for the FESEM

Enaminones in a multicomponent synthesis of 4-aryldihydropyridines for potential applications in photoinduced intramolecular electron-transfer systems

• Nouria A. Al-Awadi,
• Maher R. Ibrahim,
• Mohamed H. Elnagdi,
• Elizabeth John and
• Yehia A. Ibrahim

Beilstein J. Org. Chem. 2012, 8, 441–447, doi:10.3762/bjoc.8.50

• -naphthyl) and 4-(phenanthren-9-yl)dihydropyridine derivatives exhibited an interesting photoluminescence behavior, which suggests their potential application as suitable photoinduced intramolecular electron-transfer systems. Keywords: enaminones; 1,4-dihydropyridines; microwaves; multi-component reactions

• ; photoluminescence; Introduction There is a lot of interest in supramolecular assemblies based on transition-metal ions, which have proved to be useful for a variety of light-induced applications, from molecular machines to systems that mimic chlorophyll photosynthesis [1][2][3][4][5][6]. Recently, 4-aryl-2,6

• compounds gave fluorescence spectra (Figure 3 and Figure 4) with λmax = 454–492 nm (Table 2). This photoluminescence behavior of 6 and 7 resembles that of dihydropyridinedicarboxylate derivatives [7][8], which suggests their potential application as suitable photoinduced intramolecular electron-transfer

Laterally substituted symmetric and nonsymmetric salicylideneimine-based bent-core mesogens

• Sonja Findeisen-Tandel,
• Wolfgang Weissflog,
• Ute Baumeister,
• Gerhard Pelzl,
• H. N. Shreenivasa Murthy and
• Channabasaveshwar V. Yelamaggad

Beilstein J. Org. Chem. 2012, 8, 129–154, doi:10.3762/bjoc.8.15

• salicylideneaniline moieties are linked by an ester group (Scheme 1C). These compounds, which show a strong photoluminescence, exhibit typical banana phases B1 and B7 [31]. Yelamaggad et al. reported V-shaped five-ring mesogens: Two salicylideneaniline moieties are linked by ester groups to the 1,2-positions of a

Imidazole as a parent π-conjugated backbone in charge-transfer chromophores

• Jiří Kulhánek and
• Filip Bureš

Beilstein J. Org. Chem. 2012, 8, 25–49, doi:10.3762/bjoc.8.4

• (DOFIPh), based on the fluoreno[2,3-d]imidazole core, showed strong and tunable blue emission in the solid state (λmax,em = 417–526 nm in film), which makes these molecules potentially applicable as active layers for OLEDs [69]. Chromophores 62 were investigated as photoluminescence materials with λmax

Sexithiophenes as efficient luminescence quenchers of quantum dots

• Christopher R. Mason,
• Yang Li,
• Paul O’Brien,
• Neil J. Findlay and
• Peter J. Skabara

Beilstein J. Org. Chem. 2011, 7, 1722–1731, doi:10.3762/bjoc.7.202

• dot emission was studied by photoluminescence spectroscopy and compared with the performance of alkyl end-capped sexithiophenes 2a and 2b. Keywords: electrochemistry; luminescence quenching; quantum dots; sexithiophenes; synthesis; Introduction Structurally well-defined oligothiophenes as functional

• , with retention of the photoluminescence behaviour of the quantum dot [24]. Herein, we present a comparative study on the photophysical properties of sexithiophenes 1 or 2 in varying concentrations, in the presence of a fixed concentration of CdSe(ZnS) core/shell quantum dots. Our choice of compounds

• incorporate a hexadecylamine (HDA) capping group and were prepared so as to ensure that their fluorescence did not overlap with the absorption profile of the sexithiophenes under study. Thus, the photoluminescence maximum for these quantum dots under excitation of light at 590 nm is 634 nm in chloroform

Novel carbazole–pyridine copolymers by an economical method: synthesis, spectroscopic and thermochemical studies

• Aamer Saeed,
• Madiha Irfan and
• Shahid Ameen Samra

Beilstein J. Org. Chem. 2011, 7, 638–647, doi:10.3762/bjoc.7.75

• . The weight average molecular masses (Mw) of the polymers were estimated by the laser light scattering (LLS) technique. Keywords: carbazole–pyridine copolymers; fluorescent materials; organic light emitting diode (OLED); photoluminescence spectra; UV spectra; Introduction An immense research effort

• is due to the optical transition attributed to the presence of the auxochromic OH group, which increases the conjugation length [31] and becomes part of extended chromophore. This effect is absent in the other compounds. The photoluminescence spectra of the polymer solutions of series P1 and P2 in

• . DSC graph for polymer P1a. UV–vis spectra of the polymers of (a) series P1 and (b) series P2. Photoluminescence spectra of polymers P1and P2 in CHCl3 solution. (a) Polymers of P2 series in visible light; (b) observed fluorescence (CHCl3 dilute solutions) under UV irradiation (254 nm). Synthesis of the

Pyridinium based amphiphilic hydrogelators as potential antibacterial agents

• Sayanti Brahmachari,
• Sisir Debnath,
• Sounak Dutta and
• Prasanta Kumar Das

Beilstein J. Org. Chem. 2010, 6, 859–868, doi:10.3762/bjoc.6.101

• microscopy (FESEM), atomic force microscopy (AFM), photoluminescence, FTIR studies, X-ray diffraction (XRD) and 2D NOESY experiments were carried out to elucidate the different non-covalent interactions responsible for the self-assembled gelation. The formation of three-dimensional supramolecular aggregates

Conjugated polymers containing diketopyrrolopyrrole units in the main chain

• Bernd Tieke,
• A. Raman Rabindranath,
• Kai Zhang and
• Yu Zhu

Beilstein J. Org. Chem. 2010, 6, 830–845, doi:10.3762/bjoc.6.92

• ; photoluminescence; solar cell; Introduction A useful strategy in the design of new polymers for electronic applications is to incorporate chromophores which are highly absorbing and emitting in the visible and near infrared region into π-conjugated polymers chains. Potentially useful chromophores for electronic