74718-16-4Relevant academic research and scientific papers
Iodine catalysed intramolecular C(sp3)-H functionalization: synthesis of 2,5-disubstituted oxazoles from N-arylethylamides
Samanta, Supravat,Donthiri, Ramachandra Reddy,Dinda, Milan,Adimurthy, Subbarayappa
, p. 66718 - 66722 (2015/08/24)
Iodine catalyzed synthesis of 2,5-disubstituted oxazoles from N-arylethylamides through intramolecular C(sp3)-H functionalization under metal-free conditions is described. The method is tolerable to a wide range of substrates having a variety of functional groups with moderate to good yields of the products.
Metal-free dual sp3 C-H functionalization: I2- promoted domino oxidative cyclization to construct 2,5-disubstituted oxazoles
Gao, Qing-He,Fei, Zhuan,Zhu, Yan-Ping,Lian, Mi,Jia, Feng-Cheng,Liu, Mei-Cai,She, Neng-Fang,Wu, An-Xin
, p. 22 - 28 (2013/01/15)
An I2-promoted sp3 C-H functionalization has been developed for the synthesis of 2,5-disubstituted oxazoles from easily available methyl ketones and benzylamines without any metal and peroxide catalyst. This domino oxidative cyclization process involves the cleavage of C-H bond and the formation of C-N, C-O bonds.
Photophysics of a series of efficient fluorescent pH probes for dual-emission-wavelength measurements in aqueous solutions
Charier, Sandrine,Ruel, Odile,Baudin, Jean-Bernard,Alcor, Damien,Allemand, Jean-Francois,Meglio, Adrien,Jullien, Ludovic,Valeur, Bernard
, p. 1097 - 1113 (2007/10/03)
This paper evaluates the 5-aryl-2-pyridyloxazole backbone to engineer donor-acceptor fluorescent pH probes after one- or two-photon absorption. Parent fluorophores, as well as derivatives that can be used to label biomolecules, can be easily obtained in good yields. These molecules exhibit a large one-photon absorption in the near-UV range, and a strong fluorescence emission that covers the whole visible domain. The 5-aryl-2-pyridyloxazole derivatives also possess significant cross sections for two-photon absorption. Upon pyridine protonation, large shifts were observed in the absorption spectra after one- and two-photon excitation, as well as in the emission spectra. This feature was used to measure the pKa of the investigated compounds that range between 2 and 8. In most of the investigated derivatives, the pKa increased upon light excitation and protonation exchanges took place during the lifetime of the excited state, as shown by phase-modulation fluorometry analysis. Several 5-aryl-2-pyridyloxazole derivatives are suggested as efficient probes to reliably measure the pH of aqueous solutions by means of ratiometric methods that are dependent on fluorescence emission.
Combinatorial discovery of novel fluorescent dyes based on Dapoxyl
Zhu, Qing,Yoon, Hai-Shin,Parikh, Puja B.,Chang, Young-Tae,Yao, Shao Q.
, p. 5083 - 5086 (2007/10/03)
We have developed a combinatorial method for the fast and effective synthesis of a library based on a known fluorescent dye, Dapoxyl using parallel solution-phase chemistry. By screening the 140 new compounds using fluorescence-based assays, we identified three new fluorescent dyes with novel properties.
SPECTRAL-LUMINISCENCE PROPERTIES AND BASICITIES OF 2-(4-PYRIDYL)-5-(4-R-PHENYL)OXAZOLES
Afanasiadi, L. Sh.,Tur, I. N.,Kurapov, P. B.
, p. 397 - 400 (2007/10/02)
The spectral-luminiscence and acid-base properties of 2-(4-pyridyl)-5-(4-R-phenyl)oxazoles were studied.Significant ?-electron conjugation between the individual fragments exists in the molecules of these compounds in solutions at room temperature.Bathochromic and bathofluoric effects, which are particularly appreciable for electron-donor substituents, are observed when substituents R are introducted into the 5-phenyl ring.Ethanol solutions of the investigated compounds have high fluorescence quantum yields which, for some of them, are close to unity.Electron-donor substituents R increase the basicity of the pyridine nitrogen atom.
