13031-44-2Relevant articles and documents
Synthesis and properties of benzophenone-spiropyran and naphthalene-spiropyran conjugates
Tomasulo, Massimiliano,Kaanumal, Sireesha L.,Sortino, Salvatore,Raymo, Francisco M.
, p. 595 - 605 (2007)
We have designed and synthesized four compounds integrating luminescent and photochromic components in their molecular skeletons. Two of them combine a nitrospiropyran photochrome with either one or two naphthalene fluorophores and can be prepared in three synthetic steps. The other two consist of a nitrospiropyran photochrome and a benzophenone phosphore connected by either ether or ester linkages and can be prepared in six or five, respectively, synthetic steps. The luminescent components of these assemblies are expected to transfer energy intramolecularly to the photochromic species upon excitation and encourage their photoisomerization. Consistently, the phosphorescence of the benzophenone units and the fluorescence of the naphthalene components are effectively quenched when these species are connected covalently to a nitrospiropyran. Nonetheless, the photoisomerization of the photochrome becomes significantly less efficient after the covalent attachment to the luminescent partner. The fraction of incident radiations absorbed by either the benzophenone or the naphthalene fragment does not promote the isomerization of the photochromic appendage. Instead, irreversible transformations occur upon irradiation of the luminophore-photochrome assemblies. Thus, the covalent attachment of a benzophenone or a naphthalene to a nitrospiropyran is not a viable strategy to improve the photocoloration efficiency of the photochromic component. Even although the very same luminophores are known to sensitize intermolecularly the isomerization of nitrospiropyrans, the transition to covalent luminophore-photochrome assemblies tends to promote degradation, rather than sensitization, upon irradiation.
Ruthenium-Catalyzed Dehydrogenation of Alcohols with Carbodiimide via a Hydrogen Transfer Mechanism
Sueki, Shunsuke,Matsuyama, Mizuki,Watanabe, Azumi,Kanemaki, Arata,Katakawa, Kazuaki,Anada, Masahiro
, p. 4878 - 4885 (2020/06/02)
Ruthenium-catalyzed oxidative dehydrogenation of alcohols using carbodiimide as an efficient hydrogen acceptor has been developed. The protocol exhibits wide substrate scope with good to excellent yields. The results of the kinetic analysis indicated that the reaction mechanism includes the hydrogen transfer process and that the addition of carbodiimide is essential for the reaction system, and the resulting amidine also could react as a hydrogen acceptor.
Ligand-free Pd/Cu-catalyzed decarboxylative coupling of aryl iodides with α-oxocarboxylates
Ji, Yongfeng,Yang, Xiaomin,Mao, Weixi
, p. 678 - 680 (2014/09/29)
This paper describes a palladium/copper-catalyzed decarboxylative coupling of aryl iodides with α-oxocarboxylates. The cross-coupling reaction gives high chemical yields of aryl ketones and has wide functional group tolerance, making the transformation an attractive alternative to the traditional cross-coupling approaches for aryl ketones. Copyright