29778-29-8Relevant articles and documents
FUNCTIONALIZED POLYCYCLIC AROMATIC HYDROCARBON COMPOUND AND LIGHT-EMITTING DEVICE INCLUDING THE SAME
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Paragraph 0168-0169, (2021/10/02)
Provided are a functionalized polycyclic aromatic hydrocarbon compound and a light-emitting device including the same. The functionalized polycyclic aromatic hydrocarbon compound is structurally stable, and exhibits high light-emission characteristics sin
Sustainable Ligand-Free Heterogeneous Palladium-Catalyzed Sonogashira Cross-Coupling Reaction in Deep Eutectic Solvents
Messa, Francesco,Dilauro, Giuseppe,Perna, Filippo M.,Vitale, Paola,Capriati, Vito,Salomone, Antonio
, p. 1979 - 1984 (2020/02/20)
The commercially available and cheap Pd/C was found to promote Sonogashira couplings in the environmentally friendly choline chloride/glycerol eutectic mixture in the absence of external ligands. Under heterogeneous conditions, (hetero)aryl iodides were successfully coupled with both aromatic and aliphatic alkynes in yields ranging from 50 to 99 % within 3 h at 60 °C. The aforementioned catalytic system proved to be effective also towards electron-rich iodides, which are notoriously known to be poorly reactive in Pd-catalyzed Sonogashira coupling reactions. The eutectic mixture and the catalyst could easily and successfully be recycled up to four times with an E-factor as low as 24.4.
Arylation of Terminal Alkynes by Aryl Iodides Catalyzed by a Parts-per-Million Loading of Palladium Acetate
Hamasaka, Go,Roy, David,Tazawa, Aya,Uozumi, Yasuhiro
, p. 11640 - 11646 (2019/12/02)
Arylation of terminal alkynes (16 varieties) by aryl iodides (28 varieties) was achieved with a mol ppm loading level of palladium catalyst, where a variety of functional groups including heteroarenes were tolerated. Thus, the arylations were carried out in the presence of palladium acetate at ppm loadings and potassium carbonate in ethanol at 80 °C to give the corresponding internal alkynes in good to excellent yields. Synthesis of 2-phenyl-3-(phenylalkynyl)benzofuran was achieved by iterative use of the alkyne arylation under mol ppm catalytic conditions. Reaction-rate analysis, transmission electron microscopic (TEM) examination of the reaction mixture, and mercury-amalgamation test were performed to gain insight into the active species of the highly active ppm catalytic species. TEM examination of the reaction mixture revealed that palladium nanoparticles were generated in situ under the reaction conditions, and their cluster size was variable during the catalytic reaction. A variation in size of palladium particles suggested that the composition-decomposition process of Pd aggregates should take place in situ via monomeric palladium(0) species and/or fine palladium(0) clusters, which might be real catalytic species in this reaction.
