126717-59-7Relevant articles and documents
Structure-property relationships based on Hammett constants in cyclometalated iridium(iii) complexes: Their application to the design of a fluorine-free FIrPic-like emitter
Frey, Julien,Curchod, Basile F. E.,Scopelliti, Rosario,Tavernelli, Ivano,Rothlisberger, Ursula,Nazeeruddin, Mohammad K.,Baranoff, Etienne
, p. 5667 - 5679 (2014)
While phosphorescent cyclometalated iridium(iii) complexes have been widely studied, only correlations between oxidation potential EOX and Hammett constant σ, and between the redox gap (ΔEREDOX = EOX - ERED) and emission or absorption wavelength (λabs, λem) have been reported. We present now a quantitative model based on Hammett parameters that rationalizes the effect of the substituents on the properties of cyclometalated iridium(iii) complexes. This simple model allows predicting the apparent redox potentials as well as the electrochemical gap of homoleptic complexes based on phenylpyridine ligands with good accuracy. In particular, the model accounts for the unequal effect of the substituents on both the HOMO and the LUMO energy levels. Consequently, the model is used to anticipate the emission maxima of the corresponding complexes with improved reliability. We demonstrate in a series of phenylpyridine emitters that electron-donating groups can effectively replace electron-withdrawing substituents on the orthometallated phenyl to induce a blue shift of the emission. This result is in contrast with the common approach that uses fluorine to blue shift the emission maximum. Finally, as a proof of concept, we used electron-donating substituents to design a new fluorine-free complex, referred to as EB343, matching the various properties, namely oxidation and reduction potentials, electrochemical gap and emission profile, of the standard sky-blue emitter FIrPic.
INHIBITOR OF CASEIN KINASE 1DELTA AND CASEIN KINASE 1EPSILON
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, (2011/12/13)
There is provided an inhibitor that inhibits casein kinase 1δ and casein kinase 1ε, and thus, there is also provided a pharmaceutical agent useful for the treatment and/or prevention of a disease, with the pathological condition of which the mechanism of activation of casein kinase 1δ or casein kinase 1ε is associated. Particularly, the above-described inhibitor is used to provide a pharmaceutical agent useful for the treatment of circadian rhythm disorder (including sleep disorder), central neurodegenerative disease, and cancer. An inhibitor of casein kinase 1δ and casein kinase 1ε, which comprises, as an active ingredient, an oxazolone derivative represented by the following general formula (1), a salt thereof, a solvate thereof, or a hydrate thereof: [wherein, in the formula (1), each of R1 and R2 independently represents any one of a substituted or unsubstituted 6-membered or 5-membered heterocyclic group optionally having a condensed ring, a substituted or unsubstituted aromatic hydrocarbon group optionally having a condensed ring, and a substituted or unsubstituted aromatic hydrocarbon lower alkyl group or aromatic hydrocarbon lower alkenyl group optionally having a condensed ring.]
Total synthesis of (+)-lyconadin A and related compounds via oxidative C-N bond formation
West, Scott P.,Bisai, Alakesh,Lim, Andrew D.,Narayan, Raja R.,Sarpong, Richmond
body text, p. 11187 - 11194 (2009/12/06)
The formation of carbon-nitrogen (C-N) bonds is a fundamental bond construction in organic synthesis and is indispensable for the synthesis of alkaloid natural products. In the context of the synthesis of the architecturally complex Lycopodium alkaloid lyconadin A, we have discovered a highly efficient oxidative C-N bond forming reaction that relies on the union of a nitrogen anion and a carbon anion. Empirical evidence amassed during our synthetic studies suggests that the mechanism of the C-N bond forming process encompasses polar as well as radical processes. Herein, we present our study of this novel C-N bond forming reaction and its application to the enantioselective total synthesis of lyconadin A and related derivatives.
