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We report the synthesis and optoelectronic properties of a series of nine triphenylamine derivatives. They were synthesized by Suzuki cross-coupling reactions and characterized by elemental analysis, nuclear magnetic resonance, ultraviolet visible absorption spectra, fluorescence spectra, and cyclic voltammetry. All compounds exhibit reversibly electrochemical behavior. In solid state, compounds 5 and 9 emit near violet blue and compounds 1, 2,4,6, 7, and 8 emit deep blue or pure blue and compound 3 emits green. Of all of these compounds, compounds 1, 3, 4, and 8 exhibit high fluorescence quantum yields (44%-68%) with the best coplanarity. Compared with them, compounds 5 and 9 have the lowest fluorescence quantum yields due to the least coplanarity. With the similarity in structure with those reported in literature, these compounds can be potentially useful for blue-emitting, host, and up-converting materials. Key words: triphenylamine, violet blue, blue-emitting, quantum yield, electrochemistry. On presente la synthese et les proprietes optoelectroniques d'une serie de neuf derives de la triphenylamine. Ces derives ont ete synthetises par des reactions de couplage de Suzuki et caracterises en se basant sur l'analyse elementaire, la resonance magnetique nucleaire, les spectres d'absorption ultraviolet-visible, les spectres de fluorescence et la voltammetrie cyclique. Tous les composes presentent un comportement electrochimique reversible. A l'etat solide, les composes 5 et 9 emettent dans le bleu tirant sur le violet, les composes 1, 2,4, 6, 7 et 8 emettent dans le bleu fonce ou le bleu pur, et le compose 3 emet dans le vert. Les composes 1,3,4 et 8 presentent un rendement quantique de fluorescence eleve (44%-68%) et la meilleure coplanarite. Comparativement, les composes 5 et 9, qui possedent le moins de coplanarite, donnent le rendement quantique de fluorescence le plus faible. En raison de la similarite entre leur structure et celle des composes decrits dans la litterature, ces composes pourraient etre utiles a titre de materiaux emettant dans le bleu, de materiaux hotes et de materiaux convertisseurs elevateurs de frequence. [Traduit par la Redaction] Mots-cles: triphenylamine, bleu-violet, emettant dans le bleu, rendement quantique, electrochimie., Introduction Organic light-emitting diodes (OLEDs) have been widely recognized as the next-generation technology for flat panel displays and white lighting. (1-5) In recent years, there has been considerable interest in [...]

The studies of photophysical and photochemical properties of imipramine (IPA) and its derivatives are reported. The results provide insight into phototoxicity of these drugs which are used for the treatment of depression and other mental disorders.

High-resolution absorption spectra of gas-phase monomethylamine (MMA, [CH.sub.3][NH.sub.2]) and dimethylamine [DMA, [([CH.sub.3]).sub.2]NH] in the region of the first overtone of the NH stretch vibration are reported. Measurements were performed with a near-infrared laser spectrometer based on the cavity-ringdown (CRD) detection technique. The minimum detectable absorption coefficient for the CRD detection setup is [[alpha].sub.min] = 1.55 x [10.sup.-8] [cm.sub.-1] (for SNR = 1). This corresponds to detection limits of 350 parts in [10.sup.9] (ppb) for MMA and 1.6 parts in [10.sup.6] (ppm) for DMA in synthetic gas mixtures under interference-free conditions, or 10 ppm and 60 ppm for MMA and DMA, respectively, in the case of gas mixtures such as exhaled human breath containing [H.sub.2]O, C[O.sub.2], and other absorbing gases in this range. OCIS codes: 300.6360, 140.3600, 170.4580.

A study was conducted to explore the effects of oxygen in the photoreduction of 1,4-benzoquinone (BQ), 1,4-naphthoquinone (NQ), and a series of derivatives in aqueous solution in the presence of acetonitrile and formate, aliphatic amines. The overall reaction is observed to be oxidation of the donors and conversion of oxygen via the hydroperoxyl/superoxide radical into hydrogen peroxide.

Fluorescence behaviors of a triethylenetetramine bearing anthracene (AN) and benzophenone (BP) fragments at the respective ends, is studied in water, where effects of pH ([H.sup.+]) and metal cations on the emission properties is studied in detail. Results reveal that triethylenetetramine bearing AN and BP fragments acts as a fluorescent logic gate with either-or switchable dual logic functions, driven by [H.sup.+] and metal cations.

The coadsorption of CO and triethylenediamine (TEDA) on a high-area gamma-Al2O3 surface is investigated with use of transmission FTIR spectroscopy. The results have showed that strong bonding of adsorbed CO with TEDA molecules does not occur and that the observed decrease in the binding energy of CO when coadsorbed with TEDA on gamma-Al2O3 is expected.

The novel synthetic strategy and optical properties of highly fluorescent, triazine-amine conjugated oligomers are described. Results reveal that the emission properties are due to the strong electron-donating and accepting abilities of the NMe and triazine moieties, respectively.

A bis-azamacrocyclic anthracene, which has two a 12-membered cyclic tetramine connected through a 9,10-dimethylanthracene spacer, is synthesized as a new fluorescent chemosensor for detection of pH and metal cations in aqueous solution. The findings suggest potential utilities of bis-azamacrocyclic anthracene as a new type fluorescent chemosensor for the detection of cations in aqueous solution.

The conformational space of tryptamine is investigated using rotationally resolved laser-induced fluorescence. The microsolvation of tryptamine with a single water molecule freezes out one specific conformer of the possible 27 in tryptamine.

The Ge (100) surface with organic molecules was examined for its reaction with a model system of six cyclic, five-membered aliphatic and aromatic amines using multiple internal reflection infrared spectroscopy in combination with density functional theory cluster calculations. The reactions of pyrrolidine, N-methylprrolidine, pyrrole and N-methylpyrrole were then probed on the Si (100) 2*1 surface for comparison.

A new series of intramolecular charge transfer (ICT) molecules are prepared by attaching various strong electron-withdrawing groups to a triphenylamine backbone and their chemical structures and optoelectronic properties are examined. The compounds have displayed intensive ICT interactions that have led to substantial extension of their absorption spectral response, which is used for efficient solar cells.

The infrared multiphoton dissociation spectroscopy technique is employed to explain the mechanisms involved in the naphthol coupling taking place in the gas phase. The various steps and the intermediates involved in the coupling reaction are also talked about.

The highly enantioselective hydrogenation of cyclic N,N-dialkyl enamines by using chiral iridium complexes of spiro phosphoramidites and it application in the synthesis of optically active cyclic tertiary amines, including the natural product crispine A is described. The asymmetric hydrogenation of enamine is performed under the optimized conditions by using the iridium catalyst to produce crispine A in 97% yield.

Apex-N-substituted azabicycloalkane is used as an amino auxochrome group in a donor-acceptor chromophore. The studies have shown that the use of the 7-azanorbornyl moiety as the electron donating component in a rhodamine chromophore has induced remarkable beneficial effects on emission efficiency and photostability as compared to a tetramethylrhodamine analogue.

The spectral changes associated with single-turnover reoxidation by [O.sub.2] of substrate-reduced Arthrobacter globiformis amine oxidase (AGAO) are measured under a wide range of conditions. Global analysis of the kinetics and the transient absorption spectra are consistent with an inner-sphere reaction of the Cu(I)-semiquinone intermediate with [O.sub.2] and are inconsistent with an outer-sphere mechanism for the reaction of the reduced enzyme with [O.sub.2].

An original new family of trinaphthylamine derivatives that are efficient fluorophores for two-photon absorption (2PA) absorption is described. The high 2PA cross-sections have represented an interesting improvement as compared to the triphenylamine derivatives.

The high-temperature ammonia treatment of HY zeolite has produced a mixture of surface and frameworks substitutions, the latter confined to reactions that replace Bronsted acid sites with N[H.sub.2] groups. The major result is that nitrogen substitution has left the framework intact, thus paving the way for base-catalyzed reactions using strong amine-like bases.

The structural, optical and electrical properties of films of spin-cast, oleate-capped PbSe nanocrystals, which are treated thermally or chemically in solutions of hydrazine, methylamine or pyridine to produce electronically coupled nanocrystal solids, are described. These chemically treated films have oxidized rapidly in air to yield highly conductive p-type nanocrystal solids.

The first study of nucleophilic ring-opening of nosylamide-activated aziridines under microwave irradiation conditions in solid-phase synthesis (SPS) is described. The results obtained can be used to construct new polyamine scaffolds suitable for application in medicinal chemistry as well as novel types of peptide modification.

The optimization of the repetitive steps involved in the synthesis of the sulfonimide-based dendrimers via systematic analysis of the persulfonylation of branched aromatic oligoamines with different arylsulfonyl chlorides is reported. The optimized method yielded the fourth generation N- and pentaphenylene-centered dendrimers with 16 and 32 peripheral groups.

The conversion of a tethered rhodamine B dyad from an H-dimer form to a J-dimer form upon addition cucurbit[7]uril (CB7) is demonstrated. The results from the study could be applied to design the CB7-protected multichromophoric systems that retain desirable photophysical properties.

The synthesis and chiroptical spectroscopic properties of two diastereomers of N-[alpha]-phenylethyl-t-butylsulfinamide derived from (-)-(S)-[alpha]-phenylethyl amine, a (+)-diastereomer and a (-)-diastereomer is described. The results based on the experimental and density functional theory (DFT)-predicted VCD spectra provide insights into absolute configurations and dominant conformations for two diastereomers.

The time-dependent density functional theory is employed to study the geometries and resonance Raman scattering of different excited states of rhodamine 6G (R6G) in vacuum and ethanol. The different states are shown to exhibit similar vibronic but different solvent effects and structure.

A computational study is used for evaluating tertiary amines whose radical cations might lose hydrogen atoms from positions other than the [alpha] carbons. The main aim was to find photochemically activated reducing agents for carbon dioxide that are regenerated in a separate photochemical reaction.

The protonation of photosensitizers whose chromophores contain amine functional groups has adversely affected the singlet oxygen yield in aqueous and non-aqueous media. The analysis is helpful in understanding and controlling the behavior of photosensitizers in systems with microheterogeneous domains that have appreciable pH gradients.

The reduction of C[O.sub.2] by amines-primarily triethylamine is determined by calculating at the MP2/aug-cc-pVDZ/MPWB1K/aug-cc-pVDZ levels. The result of the reduction is observed to be a closed-shell iminium formate ion pair which completes the reaction by proton transfer between the ions to give an eneamine and formic acid.

A chiral tripodal ligand is prepared from primary amines containing two monosubstituted tetraphenylporphyrin (TPP) moieties. It shows that chelation of Cu(II) resulting in strong exciton coupled circular dichroism (ECCD) spectra with visible wavelength light.

The stereodefined synthesis of 10 stereoisomers of 2,6-bis[1-(1-phenylethylamino)ethyl]pyridines in a stereochemically pure form is presented. The synthesis, which involves stepwise or simultaneous stereospecific substitution of pyridinylethylmethansulfonate or toluenesulfonate with (R)- or (S)-phenyl-ethylamine is found to be efficient with high enantio- and diastereo selectivities to provide optically pure triamine molecules.

The femtosecond nonresonant ionization of organic amines was examined with very low ionization potentials and quantitative evaluation of suppressed ionization relative to single active electron was done by comparing the saturation intensity. Ammosov-Delone-Krainov theory was found to be useful in predicting ionization yield even for molecules with low ionization potentials and the degree of suppression was smaller than that of benzene.

The novel products of glutathione with [{PtCl(en)}(sub 2-) mu-{H2N(CH2)6NH2}]Cl2 under physiological conditions (pH 7.35, 37 degree Celsius) are described. The cis dinuclear geometry results in formation of a structurally unique 11-membered macrochelate in which the two Pt centers are bridged by both the diamine linker and the glutathione thiolate, thus representing a structure for glutathione adducts of platinum.

The dynamic compaction of granular beds of the propellent cyclotetramethylene tetranitramine (HMX) is investigated using a modified split Hopkinson pressure bar system. Microfine HMX behaved like low porosity conventional HMX beds in all cases.

Wavelength is used as a tunable parameter to achieve selective control of the phototophysics of two novel asymmetric bichromophoric dyads composed of naphthalene units, with different properties connected by an amide spacer. The results demonstrate that it is possible to control configuration-dependent interactions in the excited state by wavelength tuning.

The asymmetric coupling of various phenol or aniline derivatives with bulky aryllead triacetates is examined by using optically active amines, strychnine and brucine. Results suggested the effectiveness of lithiation in phenol coupling and magnesation of anilines is critical for aniline coupling.

The study objective is to develop a 'DR fitting' approach for the IR reflection-absorption spectroscopy (IRRAS) spectra and to test it on the molecular orientation (MO) measurements on primary ion-chain (C16) amine and alcohol adsorbed on quartz. This method is based on fitting of the dichroic ratio by the theoretical values calculated with the linear approximation formulas.

The assembly of dithiocarbamate (DTC) ligands on Au surfaces by exposure to carbon disulfide and secondary amine is described. It is shown that a variety of secondary amines can condense with carbodithioate (CS2) onto Au surfaces at room temperature without additional base to form ligands, which are stable in acidic and basic aqueous environments and in the presence of competing surfactants.

An experimental study is conducted to know the repercussions when the polyene chain is elongated on the optical materials of metal pyridyl complexes. Variety of molecules that have huge beta values consists of conjugated alpha systems that possess electron donor (D) and acceptor (A) sets, and their linear optical materials are governed by powerful D(alpha), which leads to alterations in the charge transfer of A(alpha).