Novel quinoxalinophenanthrophenazine-based molecules as sensors for anions: synthesis and binding investigations

Nonsymmetric Pyrene-Fused Pyrazaacenes via Green Oxidation of 2,7-Di-tert-butylpyrene

We disclose a four-step oxidize-condense-oxidize-condense synthesis pathway to prepare nonsymmetric pyrene-fused pyrazaacenes (PPAs) using our recently discovered oxidation conditions for 2,7-di-tert-butylpyrene. The new pathway results in marked improvements in yields and simplifies purification as compared with the sequential condensation strategy previously employed to make these compounds.

Columnar Mesomorphism of Board-Shaped Perylene, Diketopyrrolopyrrole, Isoindigo, Indigo, and Quinoxalino-Phenanthrophenazine Dyes

The properties of organic dyes depend as much on their intermolecular interactions as on their molecular structure. While it is generally predictable what supramolecular structure would be ideal for a specific application, the generation of specific supramolecular structures by molecular design and suitable processing methods remains to be a challenge. A versatile approach to different supramolecular structures has been the application of mesomorphism in conjunction with alignment techniques and self-assembly at interfaces. Reviewed here is the columnar mesomorphism of board-shaped dyes perylene, indigo, isoindigo, diketopyrrolopyrrole, and quinoxalinophenanthrophenazine. They generate a larger number of different supramolecular structures than conventional disc-shaped (discotic) mesogens because of their non-circular shape and directional intermolecular interactions. The mesomorphism of all but the perylene derivatives is systematically and comprehensively covered for the first time.

Heterocyclic Nanographenes and Other Polycyclic Heteroaromatic Compounds: Synthetic Routes, Properties, and Applications

Two-dimensionally extended, polycyclic heteroaromatic molecules (heterocyclic nanographenes) are a highly versatile class of organic materials, applicable as functional chromophores and organic semiconductors. In this Review, we discuss the rich chemistry of large heteroaromatics, focusing on their synthesis, electronic properties, and applications in materials science. This Review summarizes the historical development and current state of the art in this rapidly expanding field of research, which has become one of the key exploration areas of modern heterocyclic chemistry.

Dithieno[3,2-a:2′,3′-c]phenazine-based chemical probe for anions: a spectroscopic study of binding

The synthesis and binding studies of N,N′-(2,5-bis(4-(tert-butyl)phenyl)dithieno[3,2-a:2′,3′-c]phenazine-9,10-diyl)bis(4-methylbenzenesulfonamide) (1) are reported.

Low-LUMO pyrene-fused azaacenes

A series of pyrene-fused azaacenes with four and six linearly fused rings that possess LUMO levels between -3.7 and -4.3 eV is reported. These LUMO values are remarkably lower than those typically observed for pyrene-fused azaacenes, even for systems with sixteen linearly fused rings, and are comparable to those observed for state-of-the-art n-azaacenes.

Highly specific and reversible fluoride sensor based on an organic semiconductor

A novel sulfonamide-conjugated benzo-[2,1-b:3,4-b']bithiophene semiconductor has been designed and synthetized in order to develop a probe for specific detection of anions both in the homogeneous (solution) and heterogeneous phase. Its photophysical and electrochemical data were reported in this study. On the basis of the optical and NMR titrations analysis, the chelator was found to be highly selective for fluoride compared to others anions (Ka = 1.6 × 10(4) M(-1) in dimethyl sulfoxide (DMSO)). In addition, from an intricate sample, the novel chelator shows exceptional specificity toward fluoride and reveals a complete reversibility after addition of trifluoroacetic acid (TFA). Sensing films were obtained by electrochemical polymerization of the probe on an electrode surface, which clearly show effective detection of fluoride.

Chromogenic and fluorogenic chemosensors and reagents for anions. A comprehensive review of the years 2010-2011

This review focuses on examples reported in the years 2010-2011 dealing with the design of chromogenic and fluorogenic chemosensors or reagents for anions.

Versatile 2,7-substituted pyrene synthons for the synthesis of pyrene-fused azaacenes

A new synthetic route to prepare a series of versatile 2,7-substituted pyrene synthons for the synthesis of pyrene-fused azaacenes is described. By using such synthons, a library of eight pyrene-fused azacenes with different electronic structures and in most cases with enhanced solubility has been synthesized and characterized.

Synthesis of 3,5-diaryl substituted indole derivatives and its selective iodide ion chemosensing

In this contribution, we have synthesized series of 1-ethyl-3,5-bis[2-(aryl)ethenyl]-1H-indole based derivatives with different functional groups using Wadsworth-Emmons coupling. The sensing ability of the receptors has been studied for halides like tetrabutylammonium fluoride, chloride, bromide, iodide and bisulphate by UV-vis spectroscopy methods. In THF solution, compound A-E exhibits excellent selectivity with iodide ions over the other ions like tetrabutylammonium bromide (TBABr), tetrabutylammonium chloride (TBACl), tetrabutylammonium fluoride (TBAF) and tetrabutylammonium bisulphate (TBAHSO(4)). The indole cores were observed effectively and selectively recognized biologically important iodide was reported. Significant absorption change was observed only for tetrabutylammonium iodide and no change with other anions. The absorption spectra indicated the formation of complex between host and guest is in 1:1 stoichiometric ratio. The association constants of A-E for iodide ions were found to be 3.2 × 10(4) M(-1), 3.9 × 10(4) M(-1), 4.2 × 10(3) M(-1), 2.9 × 10(3) M(-1) and 2.14 × 10(3) M(-1), respectively.