A Dual Emissive Coumarin–urea Derivative with an Electron‐withdrawing Substituent in the Presence of Acetate Anion

2019 ◽  
Vol 96 (1) ◽  
pp. 21-27
Author(s):  
Tomoyuki Shinoda ◽  
Yoshinobu Nishimura ◽  
Tatsuo Arai
2007 ◽  
Vol 5 (1) ◽  
pp. 316-329 ◽  
Author(s):  
Rafał Frański ◽  
Błażej Gierczyk ◽  
Grzegorz Schroeder ◽  
Stefan Pieper ◽  
Andreas Springer ◽  
...  

AbstractBy mixing 1,2,4-triazolium salts (precursors of N-heterocyclic carbenes 1–6) with mercury acetate, a number of complexes have been obtained under electrospray ionization condition. Carbenes 1 and 2 contain one carbene center; therefore, they are able to bond only one mercury cation. Carbenes 3–5 contain two carbene centers; therefore, they can bond two mercury cations. Mercury complexes of 1–5 always contain an acetate anion attached to a mercury cation. Carbene 6 also contains two carbene centers; however, its structure allows formation of a complex containing mercury bonded simultaneously to both centers, therefore, the complex that does not contain an acetate anion. The MS/MS spectra taken for complexes of carbenes 1–5 have shown formation of a cation corresponding to N1 substituent (adamantyl or benzyl), and those of complexes of carbenes 3–5 (doubly charged ions) have also shown the respective complementary partner ions. Mercury complex of 2 has yielded some other interesting fragmentation pathways, e.g. a loss of the HHgOOCCH3 molecule. The fragmentation pathway of the mercury complexes of 6 was found to be complicated.


ChemBioChem ◽  
2019 ◽  
Vol 20 (5) ◽  
pp. 710-717 ◽  
Author(s):  
Meinrad Drexel ◽  
Johannes Kirchmair ◽  
Sandra Santos-Sierra

InterConf ◽  
2021 ◽  
pp. 970-978
Author(s):  
Z. Nizomov ◽  
M. Asozoda ◽  
A. Olimi ◽  
A. Karimzoda

The absorption of ultrasonic waves in the frequency range from 6 to 146 MHz in aqueous solutions of sodium acetate, sodium chloride and calcium has been studied. It was found that only in solutions of calcium cations and acetate anion present simultaneously, relaxation absorption of ultrasonic waves is observed. The experimental data obtained indicate that the observed relaxation absorption of ultrasound in the studied frequency range by an aqueous solution of calcium acetate is associated with the interaction of the acetate anion with the calcium cation in the solution.


2015 ◽  
Vol 44 (34) ◽  
pp. 15316-15323 ◽  
Author(s):  
Hiroki Onoda ◽  
Osami Shoji ◽  
Yoshihito Watanabe

Wild-type cytochrome P450SPα and cytochrome P450BSβ can catalyze the oxidation of non-native substrates by performing the reaction at a high concentration of the acetate anion.


2018 ◽  
Vol 43 (2) ◽  
pp. 121-135 ◽  
Author(s):  
Stanislav Bakhtin ◽  
Elena Shved ◽  
Yuliia Bespal'ko ◽  
Yuliia Stepanova

The mechanism of action of nucleophilic and non-nucleophilic bases in the system “acetic acid (HOAc) – epichlorohydrin (ECH) – R3X (R = alkyl, X = N, P)” has been studied. The observed orders of the reaction with respect to the components were found. It has been proved that the catalytic activity of the starting bases is determined by their nucleophilicity, rather than basicity. It is shown that the crucial stage of the reaction is the quaternisation of the starting base with the formation of a reactive intermediate, the acetate anion. Monitoring of possible paths of oxirane ring-opening by the initial base and the acetate anion was carried out. The behaviour of the model base, triphenylphosphine, in the quaternisation reaction was studied by UV spectroscopy. The rate constants of quaternisation in the reaction of tribenzylamine and triphenylphosphine with ECH have been estimated. The activation parameters of the stages of oxirane ring-opening by trimethylamine and the acetate anion were calculated using a quantum chemical method. It has been shown that the starting base attacks only the activated oxirane, while the acetate anion is capable of nucleophilic opening of both activated and non-activated ECH rings. A scheme for the catalytic opening of the oxirane ring by the bases in the system “ECH – HOAc – R3X” is proposed, which includes a series of both consecutive and parallel stages leading to the formation of the reaction product.


1999 ◽  
Vol 40 (41) ◽  
pp. 7343-7346 ◽  
Author(s):  
Kye Chun Nam ◽  
Sung Ok Kang ◽  
Hae Sang Jeong ◽  
Seungwon Jeon
Keyword(s):  

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Feriel Aouatef Sahki ◽  
Mehdi Bouchouit ◽  
Sofiane Bouacida ◽  
Lyamine Messaadia ◽  
Elsa Caytan ◽  
...  

Abstract 2-(1H-benzo[d]imidazol-2-yl)quinoline (BQ) as ligand and three coordination compounds of formula {Zn(BQ)Cl2} (1), {Pb(BQ)Cl2} n (2) and {[Cu(BQ)2(OC(O)CH3)]OC(O)CH3 · CH3COOH} (3) have been synthesized and fully characterized. The complexes crystallize in triclinic space group P 1 ‾ $P‾{1}$ . In complexes 1 and 2, the coordination geometry is a distorted tetrahedral environment around the zinc center and a distorted sixfold coordination geometry around the lead center, respectively. In complex 3 the central Cu(II) center is in a trigonal bipyramidal coordination geometry. The Cu(II) ion is surrounded by two bidentate 2-(2′-quinolyl)benzimidazole (BQ) ligands and one coordinated acetate molecule. One further acetate anion associated by a strong hydrogen bond with a molecule of acetic acid balances the charge of the compound.


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