447-61-0Relevant articles and documents
Efficient and selective oxidation of benzylic alcohol by O2 into corresponding aldehydes on a TiO2 photocatalyst under visible light irradiation: Effect of phenyl-ring substitution on the photocatalytic activity
Higashimoto, Shinya,Suetsugu, Nobuaki,Azuma, Masashi,Ohue, Hiroyoshi,Sakata, Yoshihisa
, p. 76 - 83 (2010)
The highly efficient and selective photocatalytic oxidation of benzyl alcohol and its derivatives substituted with-OCH3,-CH 3,-C(CH3)3,-Cl,-CF3 and-NO 2 into corresponding aldehydes has been successfully carried out on TiO2 in the presence of O2 under visible light irradiation. The photocatalytic activity for the formation of the aldehyde was evaluated by a pseudo-first-order reaction, and it was found that the activity is enhanced by phenyl-ring substitution with the electron-releasing groups (-OCH3,-CH3,-C(CH3)3) and the electron-withdrawing groups (-Cl,-CF3 and-NO2). The effects of the substituents and their orientation on the photocatalytic performance of selective oxidation reaction are discussed here. It was shown that the photocatalytic activities are influenced not only by the oxidative potentials of the reactants but also by the stability of the resonant structures of the benzylic alcohol radicals formed by oxidation with a hole, leading to further reactions to form corresponding aldehydes.
An isocyanide ligand for the rapid quenching and efficient removal of copper residues after Cu/TEMPO-catalyzed aerobic alcohol oxidation and atom transfer radical polymerization
Bulska, Ewa,Enciso, Alan E.,Fantin, Marco,Grela, Karol,Lorandi, Francesca,Matyjaszewski, Krzysztof,Nogas, Wojciech,Piatkowski, Jakub,Ruszczynska, Anna,Szczepaniak, Grzegorz,Yerneni, Saigopalakrishna S.
, p. 4251 - 4262 (2020/05/13)
Transition metal catalysts play a prominent role in modern organic and polymer chemistry, enabling many transformations of academic and industrial significance. However, the use of organometallic catalysts often requires the removal of their residues from reaction products, which is particularly important in the pharmaceutical industry. Therefore, the development of efficient and economical methods for the removal of metal contamination is of critical importance. Herein, we demonstrate that commercially available 1,4-bis(3-isocyanopropyl)piperazine can be used as a highly efficient quenching agent (QA) and copper scavenger in Cu/TEMPO alcohol aerobic oxidation (Stahl oxidation) and atom transfer radical polymerization (ATRP). The addition ofQAimmediately terminates Cu-mediated reactions under various conditions, forming a copper complex that can be easily separated from both small molecules and macromolecules. The purification protocol for aldehydes is based on the addition of a small amount of silica gel followed byQAand filtration. The use ofQA?SiO2synthesizedin situresults in products with Cu content usually below 5 ppm. Purification of polymers involves only the addition ofQAin THF followed by filtration, leading to polymers with very low Cu content, even after ATRP with high catalyst loading. Furthermore, the addition ofQAcompletely prevents oxidative alkyne-alkyne (Glaser) coupling. Although isocyanideQAshows moderate toxicity, it can be easily converted into a non-toxic compound by acid hydrolysis.
AN IMPROVED PROCESS FOR PREPARATION OF TRIFLUOROMETHYLBENZALDEHYDES AND INTERMEDIATES THEREOF
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Page/Page column 7, (2019/04/10)
The present invention provides an in-situ process for preparation of a compound of formula 1 and intermediate thereof, These compounds are useful chemical intermediates for the production of pesticides and pharmaceutical products.
