1440422-60-5Relevant academic research and scientific papers
Photocatalytic atom transfer radical addition to olefins utilizing novel photocatalysts
Voutyritsa, Errika,Triandafillidi, Ierasia,Tzouras, Nikolaos V.,Nikitas, Nikolaos F.,Pefkianakis, Eleftherios K.,Vougioukalakis, Georgios C.,Kokotos, Christoforos G.
supporting information, (2019/05/24)
Photocatalysis is a rapidly evolving area of research in modern organic synthesis. Among the traditional photocatalysts, metal-complexes based on ruthenium or iridium are the most common. Herein, we present the synthesis of two photoactive, ruthenium-based complexes bearing pyridine-quinoline or terpyridine ligands with extended aromatic conjugation. Our complexes were utilized in the atom transfer radical addition (ATRA) of haloalkanes to olefins, using bromoacetonitrile or bromotrichloromethane as the source of the alkyl group. The tailor-made ruthenium-based catalyst bearing the pyridine-quinoline bidentate ligand proved to be the best-performing photocatalyst, among a range of metal complexes and organocatalysts, efficiently catalyzing both reactions. These photocatalytic atom transfer protocols can be expanded into a broad scope of olefins. In both protocols, the photocatalytic reactions led to products in good to excellent isolated yields.
Novel Ru(ii) sensitizers bearing an unsymmetrical pyridine-quinoline hybrid ligand with extended π-conjugation: Synthesis and application in dye-sensitized solar cells
Vougioukalakis, Georgios C.,Stergiopoulos, Thomas,Kontos, Athanassios G.,Pefkianakis, Eleftherios K.,Papadopoulos, Kyriakos,Falaras, Polycarpos
, p. 6582 - 6591 (2013/07/26)
Heteroleptic ruthenium(ii) sensitizers DV42 and DV51, encompassing a novel unsymmetrical pyridine-quinoline hybrid ligand with extended π-conjugation, were synthesized, characterized, and utilized in nanocrystalline dye-sensitized solar cells. Due to the extended conjugation of DV42 and DV51, the absorption of the corresponding sensitized TiO2 films extends into the red spectral range, shifted by 30-40 nm relative to the absorption of TiO 2 films sensitized with the standard Z907 ruthenium(ii) dye. Contact angle measurements of DV42- and DV51-sensitized TiO2 films suggest that these films are hydrophilic with contact angle values commonly observed upon sensitization with the standard N3 ruthenium(ii) dye. Electrochemical studies of the novel ruthenium(ii) dyes show that their first oxidation potentials lie well below the I-/I3- redox potential allowing easy regeneration. The excited-state oxidation potentials of both dyes lie above the TiO2 conduction band, permitting efficient electron injection from the excited dye molecules into the semiconductor conduction band. Liquid electrolyte dye-sensitized solar cells incorporating DV42- or DV51-sensitized TiO2 photoelectrodes afford overall power conversion efficiencies of 3.24 or 4.36% respectively. These efficiencies are up to 56% of the power conversion efficiencies attained by TiO2 photoelectrodes sensitized by the benchmark Z907 ruthenium(ii) dye under similar experimental conditions.
