Search results for "Cyanine"

Electrically Conductive Phthalocyanine Assemblies. Structural and Non-Integer Oxidation Number Considerations

1990

Aggregation is a well-known phenomenon in phthalocyanine chemistry. Interactions can occur between adjacent phthalocyanine rings, both in organic and aqueous phases, resulting in coupling between the electronic states of two, or more, phthalocyanine units [1].

Addressing subphthalocyanines and subnaphthalocyanines features relevant to fluorescence imaging

2018

International audience; A series of new synthetic subphthalocyanines bear structural features aimed at allowing either fluorescence activation or a bathochromic shift of the absorption band towards the near-infrared window, relevant to optical imaging. X-ray diffraction studies of four subphthalocyanines are reported. Spectrofluorimetric studies on subnaphthalocyanines and activatable subphthalocyanine pro-fluorophores are reported.

Enhanced chemosensing of ammonia based on the novel molecular semiconductor-doped insulator (MSDI) heterojunctions

2011

Abstract A series of new molecular semiconductor-doped insulator (MSDI) heterojunctions as conductimetric transducers to NH3 sensing were fabricated based on a novel semiconducting molecular material, an amphiphilic tris(phthalocyaninato) rare earth triple-decker complex, Eu2[Pc(15C5)4]2[Pc(OC10H21)8], quasi-Langmuir–Shafer (QLS) film, as a top-layer, and vacuum-deposited and cast film of CuPc as well as copper tetra-tert-butyl phthalocyanine (CuTTBPc) QLS film as a sub-layer, named as MSDIs 1, 2 and 3, respectively. MSDIs 1–3 and respective sub-layers prepared from three different methods were characterized by X-ray diffraction, electronic absorption spectra and current–voltage (I–V) measu…

Tuning the semiconducting nature of bis(phthalocyaninato) holmium complexes via peripheral substituents

2012

The semiconducting properties of the heteroleptic and homoleptic bis(phthalocyaninato) holmium complexes bearing electron-withdrawing phenoxy substituents at the phthalocyanine periphery, namely Ho(Pc)[Pc(OPh)8] (1) and Ho[Pc(OPh)8]2 (2) [Pc = unsubstituted phthalocyaninate; Pc(OPh)8 = 2,3,9,10,16,17,23,24-octaphenoxyphthalocyaninate] have been investigated comparatively. Using a solution-based Quasi–Langmuir–Shafer (QLS) method, the thin solid films of the two compounds were fabricated. The structure and properties of the thin films were investigated by UV-vis absorption spectra, X-ray diffraction (XRD) and atomic force microscopy (AFM). Experimental results indicated that H-type molecular…

Two-Step Solution-Processed Two-Component Bilayer Phthalocyaninato Copper-Based Heterojunctions with Interesting Ambipolar Organic Transiting and Eth…

2016

International audience; The two-component phthalocyaninato copper-based heterojunctions fabricated from n-type CuPc(COOC8H17)(8) and p-type CuPc(OC8H17)(8) by a facile two-step solution-processing quasi-Langmuir-Shafer method with both n/p- and p/n-bilayer structures are revealed to exhibit typical ambipolar air-stable organic thin-film transistor (OTFT) performance. The p/n-bilayer devices constructed by depositing CuPc(COOC8H17)(8) film on CuPc(OC8H17)(8) sub-layer show superior OTFT performance with hole and electron mobility of 0.11 and 0.02 cm(2) V-1 s(-1), respectively, over the ones with n/p-bilayer heterojunction structure with the hole and electron mobility of 0.03 and 0.016 cm(2) …

Oxidation of diclofenac in the presence of iron(II) octacarboxyphthalocyanine

2021

Abstract This paper presents the results of the research on the influence of catalytic activity of iron(II) octacarboxyphthalocyanines (FePcOC) on the transformation of diclofenac (DCF) which is the most popular anti-inflammatory analgesic. Diclofenac poses a serious threat to the natural environment. The paper demonstrates that diclofenac, in the presence a monomeric form of iron octacarboxyphthalocyanine and hydroxyl radicals (HO•) (from H2O2), undergoes a transformation into diclofenac-2,5-iminoquinone (DCF-2,5-IQ), causing distinct changes in the UV–Vis absorption spectrum. In the presence of iron octacarboxyphthalocyanine and H2O2, the previously colourless diclofenac solution becomes …

Site-specific near-infrared fluorescent labelling of proteins on cysteine residues with meso -chloro-substituted heptamethine cyanine dyes

2018

International audience; Near-infrared (NIR) fluorescence imaging is a promising new medical imaging modality. Associated with a targeting molecule, NIR fluorophores can accumulate selectively in tissues of interest and become valuable tools for the diagnosis and therapy of various pathologies. To facilitate the design of targeted NIR imaging agents, it is important to identify simple and affordable fluorescent probes, allowing rapid labelling of biovectors such as proteins, ideally in a site-specific manner. Here, we demonstrate that heptamethine cyanine based fluorophores, such as IR-783, that contain a chloro-cyclohexyl moiety within their polymethine chain can react selectively, at neutr…

Development of Trackable Anticancer Agents Based on Metal Complexes

2016

Abstract The design of trackable anticancer agents is of major interest for the future development of therapeutics based on nonplatinum metal complexes such as Ru(II), Os(II), or Au(I) derivatives, and more particularly for the understanding of the mechanism of action of these metal-based drugs. This review reports the synthesis and the first biological studies of original trackable complexes, in which the metal complex was coupled to an imaging probe, such as a fluorophore (coumarin, borodipyrromethene derivative (BODIPY), porphyrin), or a chelating agent (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA)) for radioisotopic imaging PET (positron emission tomography) or SPECT …

Local aromaticity mapping in the vicinity of planar and nonplanar molecules

2019

We report on nucleus-independent magnetic shielding (NICS) scans over the centers of six- and five-membered rings in selected metal phthalocyanines (MPc) and fullerene C60 for more accurate characterization of local aromaticity in these compounds. Detailed tests were conducted on model aromatic molecules including benzene, pyrrole, indole, isoindole, and carbazole and subsequently applied to H2 Pc, ZnPc, Al(OH)Pc, and CuPc. Similar behavior of three selected magnetic probes, Bq, 3 He, and 7 Li+ , approaching perpendicularly the ring centers, was observed. For better visualization of shielding zone over the centers of aromatic rings, we introduced a simple mathematical procedure: the first a…

2017

The energy levels of the HOMO/LUMO Frontier orbitals and the electronic properties of phthalocyanine macrocycles can be tuned by the introduction of substituents. Starting from tetrafluorophthalonitrile, we studied the substitution of fluorine atoms by (2-thienyl)ethoxy moieties. An optimization of the experimental conditions (nature and stoichiometry of the alcohol and base, temperature) allowed us to obtain the monoalkoxy derivative with a very good yield. It was fully characterized using 19F and 1H NMR spectroscopies, thermal analysis and X-ray diffraction on single crystals. Then, the corresponding zinc phthalocyanine was synthesized, characterized by means of 19F and 1H NMR spectroscop…