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New quinolines bearing a 2,2′-bithiophene motif have been prepared through Ru- and In-catalyzed reactions as well as by Suzuki cross-coupling reactions. The novel quinolines have been characterized by using EI-HRMS and NMR spectroscopy. Additionally, the molecular structures of the novel quinolines were confirmed by X-ray crystallography. The photophysical and electrochemical properties of all quinoline derivatives were investigated by using absorption and luminescence spectroscopy and cyclic voltammetry. The main intense absorption bands associated with the quinoline derivatives were located between 350 and 450 nm. Intense blue-green and orange-red fluorescence, moderate Stokes shifts, and microsecond lifetimes were observed. Quinolines containing one bithiophene moiety underwent oxidation leading to dimerization, whereas bis(bithiophenyl)-substituted quinoline underwent polymerization. All the studied quinolines showed multistep reversible reduction, with 6-nitro-4-phenylquinoline being the easiest to reduce. The study of novel quinoline derivatives indicates a strong correlation between their electrochemical and spectroscopic properties and the character of the substituent (electron-donating or electron-withdrawing) in the quinoline ring. [ABSTRACT FROM AUTHOR]

Abstract: A ruthenium tetra-t-butylphthalocyanine bisaxially ligated with 3,5-bis(2,2′-bithiophene-5-yl)pyridine was synthesized from ruthenium tetra-t-butylphthalocyanine dimer. The complex was electropolymerized (in CH2Cl2 and CH3CN, with and without addition of BF3·Et2O) to yield an insoluble conjugated metallopolymer, which was characterized by cyclic voltammetry and UV–vis spectroelectrochemistry. The polymer combines the electrochemical and spectral properties of the phthalocyanine and of a polythiophene-type conjugated polymer. In the presence of BF3, the polymer can be reversibly p-doped and de-doped. Materials obtained in CH2Cl2 (tested in the same solvent) and in CH3CN/BF3 (tested in CH3CN) exhibit an unusual hysteresis of redox properties. [Copyright &y& Elsevier]

Abstract: A new strategy for the synthesis of derivatives of 5-aminoisoxazolines via tandem catalytic isomerization (of N-allyl systems to N-(1-propenyl) systems)—1,3-dipolar cycloaddition (of a stable nitrile oxide to N-(1-propenyl) systems) is presented. Rhodium and ruthenium complexes, Verkade’s superbase, and 18-crown-6/KOH system were used for the syntheses of the N-(1-propenyl) systems. 4-P-substituted isoxazoline was also synthesized via cycloaddition of diphenyl(1-propenyl)phosphine (prepared via isomerization of allyldiphenylphosphine) to 2,6-dichlorobenzonitrile oxide. All cycloadditions were regioselective but not stereoselective and not concerted. Cycloaddition to all N-(1-propenyl) systems yielded 5-N-substituted isoxazolines, but cycloaddition to P-(1-propenyl) system lead to the formation of a 4-P-regioisomer. This difference in regioselectivity is predicted by opposite FMO reactivity indices calculated for model compounds: N-(1-propenyl)amine and N-(1-propenyl)phosphine. [Copyright &y& Elsevier]