20237-92-7Relevant articles and documents
Bioinspired Catalytic Reduction of Aqueous Perchlorate by One Single-Metal Site with High Stability against Oxidative Deactivation
Liu, Jinyong,Ren, Changxu
, p. 6715 - 6725 (2021)
Reduction of perchlorate (ClO4-) with an active and stable catalyst is of great importance for environmental, energy, and space technologies. However, after the rate-limiting oxygen atom transfer (OAT) from inert ClO4-, the much more reactive ClOx- (x ≤ 3) intermediates can cause catalyst deactivation. The previous Re-Pd/C catalyst contained a [ReV(O)(hoz)2]+ site (Hhoz = 2-(2′-hydroxyphenyl)-2-oxazoline) and readily reduced ClO4-, but ClOx- intermediates led to rapid formation and hydrolysis of [ReVII(O)2(hoz)2]+. While microbes use delicate enzymatic machinery to survive the oxidative stress during ClO4- reduction, a synthetic catalyst needs a straightforward self-protective design. In this work, we introduced a methyl group on the ligand oxazoline moiety and achieved a substantial enhancement of catalyst stability without sacrificing the performance of ClO4- reduction. A suite of kinetics measurement, X-ray photoelectron spectroscopy characterization, reaction modeling, stopped-flow photospectrometry, and 1H NMR monitoring revealed the underlying mechanism. The most critical and unexpected effect of the methyl group is the deceleration (for 2 orders of magnitude) of OAT from ClO3- to [ReV(O)(Mehoz)2]+. However, the rate of OAT with ClO4- was not affected. The methyl group also slowed down the hydrolysis of [ReVII(O)2(Mehoz)2]+ and allowed the introduction of methoxy onto the phenolate moiety to further accelerate ClO4- reduction. With 1 atm H2 at 20 °C, the Re-Pd/C catalyst used [ReV(O)(MehozOMe)2]+ as the only reaction site to reduce multiple spikes of 10 mM ClO4- into Cl- without decomposition. This work showcases the significant effect of simple ligand modification in improving catalyst stability for high-performance ClO4- reduction.
OXAZOLINE COMPOUND, CROSSLINKER AND RESIN COMPOSITION
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, (2019/03/07)
PROBLEM TO BE SOLVED: To provide an oxazoline compound and trioxazoline compound optimal as crosslinkers for a wide range of uses, including a coating agent, ink, a film, a binder, and adhesive or the like. SOLUTION: The present invention provides an oxazoline compound represented by the following chemical formula, a trioxazoline compound obtained by trifunctionalizing the oxazoline compound represented by the following chemical formula, and a crosslinker and a resin composition using the oxazoline compound or the trioxazoline compound. In the formula, X is H or R-OH, R is a C1-4 linear or branched alkylene group. SELECTED DRAWING: None COPYRIGHT: (C)2019,JPO&INPIT
New sky-blue and bluish-green emitting Ir(III) complexes containing an azoline ancillary ligand for highly efficient PhOLEDs
Sarada, Ganguri,Sim, Bomi,Cho, Woosum,Yoon, Juho,Gal, Yeong-Soon,Kim, Jang-Joo,Jin, Sung-Ho
, p. 60 - 68 (2016/04/26)
Two Ir(III) complexes containing the chromophoric ancillary ligands 2-(4,5-dihydrooxazol-2-yl)phenol and 2-(1-ethyl-4,5-dihydro-1H-imidazol-2-yl)phenol, and a highly functionalized phenylpyridine derivative, 3-(4-(tert-butyl)pyridin-2-yl)-2,6-difluorobenzonitrile, as a cyclometalating ligand were designed and synthesized. The oxazoline/imidazoline heterocycle of the ancillary ligand has the effect of enhancing the metal to ligand charge transfer transition nature of the emitting excited state and the fluorine and cyano substituents on the ligand have enriched the intersystem crossings, as indicated by the experimental photoluminescence analysis. As a result, the oxazoline and imidazoline containing complexes exhibited high photoluminescence quantum yields of about >90% with bright sky-blue emission at 480 nm and bluish-green light at 495 nm, respectively, along with excellent thermal/morphological stability about 400 °C and good solubility, that make them suitable for both wet- and dry-processes. In particular, the phosphorescent OLEDs fabricated by a dry-process showed the maximum EQEs of 21.9% and 19.7% for the oxazoline and imidazoline containing complexes, respectively.