A simple and efficient dual optical signaling chemodosimeter for toxic Hg(II)

• Sabir H. Mashraqui,
• Sapna A. Tripathi,
• Sushil S. Ghorpade and
• Smita R. Britto

Beilstein J. Org. Chem. 2012, 8, 1352–1357, doi:10.3762/bjoc.8.155

• no significant interferences even in excess concentrations. Keywords: chemidosimeter; chemosensor; fluorescence; Hg(II) selective; UV–visible; visual detection; Introduction Interest continues unabatedly to design optical probes for the selective detection of metal ions of importance across

Fluorescent hexaaryl- and hexa-heteroaryl[3]radialenes: Synthesis, structures, and properties

• Antonio Avellaneda,
• Courtney A. Hollis,
• Xin He and
• Christopher J. Sumby

Beilstein J. Org. Chem. 2012, 8, 71–80, doi:10.3762/bjoc.8.7

• electron rich azole rings and methyl substituents make it particularly hard to reduce. Its first reduction potential is −1.21 V and its second was not observed as it occurs outside the solvent window for dichloromethane. Most hexaaryl[3]radialenes are orange or red in colour with UV–visible absorption

• around 443 nm (logε = 4.33), with a shoulder around 415 nm. In contrast to that, the UV–visible spectra in acetone shows two absorption peaks at around 440 and 475 nm, as well as a broad tail that extends out to approximately 600 nm. The fact that the concentrations of both solutions of 1 are similar

• point apparatus and are uncorrected. UV–visible absorption spectra were recorded on a Varian CARY 5000 spectrophotometer. Samples were dissolved in dichloromethane or acetone at a concentration of approximately 0.03 mM. Fluorescence spectra were recorded on a Varian CARY eclipse spectrophotometer

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

• ITO glass, versus Ag/AgCl reference electrode, platinum wire as the counter electrode, TBAPF6 as the supporting electrolyte in CH3CN (0.1 M), scan rate 100 mV s−1. Absorption spectra in solution (dichloromethane) and solid state. UV–visible spectroelectrochemical measurements of 1b (left) and 2b

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

• solutions using a Bruker AM-300 spectrophotometer. FTIR spectra were recorded on an FTS 3000 MX spectrophotometer. Mass spectra (EI, 70eV) were obtained on a GC–MS instrument of Agilent technologies. UV–vis and fluorescence spectra were recorded on a Perkin Elmer Lambda 20 UV–visible spectrophotometer and a

Redox-active tetrathiafulvalene and dithiolene compounds derived from allylic 1,4-diol rearrangement products of disubstituted 1,3-dithiole derivatives

• Filipe Vilela,
• Peter J. Skabara,
• Christopher R. Mason,
• Thomas D. J. Westgate,
• Asun Luquin,
• Simon J. Coles and
• Michael B. Hursthouse

Beilstein J. Org. Chem. 2010, 6, 1002–1014, doi:10.3762/bjoc.6.113

• ultimately lead to orbital overlap in one dimension, albeit through a combination of chalcogen–chalcogen and π–π contacts. The UV–visible electronic absorption spectra of compounds 3, 25, 27 and 28 were recorded in CH2Cl2 solution and are shown in Figure 6. The spectra of thione 3 and ethylenedithio-bridged

• identifying close intermolecular contacts. UV–visible spectra of 3, 25, 27 and 28 in CH2Cl2 solution. Cyclic voltammograms of compounds 3, 25, 27, and 28. Glassy carbon working electrode, using Pt wire counter and Ag/AgCl reference electrodes, in CH2Cl2 (substrate ca. 10−3 M), Bu4NPF6 supporting electrolyte

Towards racemizable chiral organogelators

• Jian Bin Lin,
• Debarshi Dasgupta,
• Seda Cantekin and
• Albertus P. H. J. Schenning

Beilstein J. Org. Chem. 2010, 6, 960–965, doi:10.3762/bjoc.6.107

• macroscopic behavior. Most of the earliest stimuli-responsive gels undergo a UV-induced transformation, which can be reversed by visible light. For example, Shinkai and coworkers demonstrated that trans-cis isomerization of gelator compounds by UV/visible light could induce a gel-sol transition [6]. Feringa

• and coworkers have reported a chiral gelator in which the supramolecular organization of the chiral assemblies can be switched using UV/visible light combined with heating and cooling [7]. Chiral gels that respond to other stimuli such as metal ions [8], guest molecules [9] and temperature [10] have

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

• , respectively. PPV-type polymers such as P-14 (Table 2) exhibit good solubility in common organic solvents, high thermal stability and a broad UV/visible absorption between 300 and 600 nm in films. Bulk heterojunction solar cells were fabricated and showed a power conversion efficiency of 0.01%. A PPE-type

Molecular recognition of organic ammonium ions in solution using synthetic receptors

• Andreas Späth and
• Burkhard König

Beilstein J. Org. Chem. 2010, 6, No. 32, doi:10.3762/bjoc.6.32

Synthesis of indolo[3,2-b]carbazole-based new colorimetric receptor for anions: A unique color change for fluoride ions

• Ajit Kumar Mahapatra,
• Giridhari Hazra and
• Prithidipa Sahoo

Beilstein J. Org. Chem. 2010, 6, No. 12, doi:10.3762/bjoc.6.12

• spectroscopic or HPLC grade. The 1H NMR spectra were recorded on a Bruker AM-500 spectrometer. The 1H NMR chemical shift values are expressed in ppm (δ). UV–visible and fluorescence spectra measurements were performed on a JASCO V530 and a PerkinElmer LS-55 spectrofluorimeter, respectively. Receptor 1 and guest

Synthesis and properties of calix[4]arene telluropodant ethers as Ag⁺ selective sensors and Ag⁺, Hg²⁺ extractants

• Yang Lu,
• Yuanyuan Li,
• Song He,
• Yan Lu,
• Changying Liu,
• Xianshun Zeng and
• Langxing Chen

Beilstein J. Org. Chem. 2009, 5, No. 59, doi:10.3762/bjoc.5.59

• oscillator and then left for 2 h at (25 ± 0.05) °C. For the determination of picrates in water phase, a cary-300 UV-visible spectrophotometer was used and absorbance readings were taken at 354 nm. Synthesis and structures of calix[4]arenes 6–8; 3, 6: n = 2; 4, 7: n = 3; 5, 8: n = 5. Synthesis of calix[4

Synthesis of mesogenic phthalocyanine-C₆₀ donor–acceptor dyads designed for molecular heterojunction photovoltaic devices

• Yves Henri Geerts,
• Olivier Debever,
• Claire Amato and
• Sergey Sergeyev

Beilstein J. Org. Chem. 2009, 5, No. 49, doi:10.3762/bjoc.5.49

• and ESI mass spectra were recorded on a Waters AutoSpec 6. UV–Visible absorption spectra were recorded on a HP 8453 spectrophotometer in a quartz cell (optical path of 1 cm). For POM experiments, a NIKON Eclipse 80i microscope equipped with a digital camera DS Camera Head D5-5M was used; temperature

A simple route for renewable nano- sized arjunolic and asiatic acids and self- assembly of arjuna- bromolactone

• Braja G. Bag,
• Partha P. Dey,
• Shaishab K. Dinda,
• William S. Sheldrick and
• Iris M. Oppel

Beilstein J. Org. Chem. 2008, 4, No. 24, doi:10.3762/bjoc.4.24

• ]. Hydrolysis of methyl asiatate (1.1 g) by refluxing with LiBr/DMF produced asiatic acid (1 g) in 90% yield [16]. All the transformations were monitored by HPLC (see Figure 1) using a reverse phase analytical column and a UV-Visible detector (at 206 nm). In the 1H-NMR spectrum (600 MHz) six singlets were