Excited-state charge coupled proton transfer reaction via the dipolar functionality of salicylideneaniline

Gao

Desalination and Water Treatment

et al. 2015

2015): Assembly of transition metal ion on cellulose surface anchored with azo-Schiff base and its catalytic activity for H 2 O 2 decomposition, Desalination and Water Treatment, A B S T R A C TTo form polymer-supported catalysts, to eliminate excess H 2 O 2 during wastewater treatment, the assembly of metal ion on cellulose was investigated. Cellulose was covalently grafted with reactive azo-Schiff base containing azo-conjugated system, 3,5-bis {2-hydroxyphenyl-5-[(2-sulfate-4-sulfatoethylsulphonyl-azobenzol) methylene amino]} benzoic acid. Metal ions, Co 2+ , Mn 2+ , and Cu 2+ , were anchored to the modified cellulose by controlling assembly. The cellulose-supported complexes were characterized and the catalytic activity for H 2 O 2 was investigated. Elemental analyses of the cellulose supported complexes, MC-Co, MC-Mn, were well agreed with the proposed composition. Three cellulose-supported complexes had strong catalytic activities for H 2 O 2 . H 2 O 2 decomposition rates in 10 min were 84.54% for MC-Co, 94.87%, for MC-Mn, and 77.21% for MC-Cu, respectively. The manganese complex had the strongest catalytic activity among them. The cellulose-supported complexes have potential application in wastewater treatment and biotechnology.

Section: Desalination and Water Treatmentmentioning

confidence: 99%

“…The proposed structures based on 3,5-diaminobenzoic acid supported 1:2 mol ratio of Schiff base ligand to the metal ion according to the references [21,27]. The metal element analyses of the Table 1.…”

Section: Assembly Of Transition Metal Ions On Cellulose Surface Anchomentioning

confidence: 99%

Assembly of transition metal ion on cellulose surface anchored with azo-Schiff base and its catalytic activity for H₂O₂ decomposition

Gao

Desalination and Water Treatment

et al. 2015

Revista Virtual De Química

“…Alguns estudos têm focado na utilização da DOX no monitoramento da ligação com DNA, outros para o monitoramento de culturas de células por fluorescência. 23,60 A classe de compostos derivados dos 2-(2'-hydroxyphenyl)benzazol, como o 2-(2'hydroxyphenyl)benzoxazol, 2-(2'hydroxyphenyl)benzthiazol e 2-(2'hydroxyphenyl)benzimidazol (ver figura 2), apresentam fluorescência devido ao processo ESIPT, possuindo seus derivados uma ampla aplicação, como laser, materiais poliméricos e estabilizantes, sendo reportados por muitos grupos de pesquisa. 13,21,61,62,63,64,65 Um dos derivados, o composto 2,1,3-benzothidiazole (BTD) e seus derivados, apresentam detecção seletiva da dupla fita de DNA (dsDNA) em células vivas, sendo uma candidata a utilização em estudos de imagem, uma vez que podem atravessar a membrana de células e se ligar seletivamente e eficientemente ao dsDNA.…”

Section: Sondas Empregadas No Diagnóstico De Doençasunclassified

Intramolecular Proton Transfer in the Excited State (ESIPT) Process: Applications in Fluorescent Probes

Rocha

Ramalho

2016

Currently the opportune diagnosis of cancer has shown a great importance, mainly by decreasing the mortality rate. Among the techniques employed to achieve the diagnosis, spectroscopy has been highlighted for presenting safe and highly accurate diagnoses. The Fluorescence Spectroscopy has become very important in cancer diagnosis, being employed in breast, oral cavity and esophagus cancer testing. The technique employs fluorophore which in many cases have groups capable of carrying out the intramolecular proton transfer in the excited state (ESIPT). These compounds may be used for various molecular targets such as cations, anions and proteins detection, besides the diagnosis of diseases. Spectroscopic probes have an important role in the development of more accurate diagnosing diseases methods, which may influence the treatment and avoid the risks of further surgery and patient death.

“…The ESIPT reaction usually involves the transfer of a hydroxyl proton to an imine nitrogen through an intramolecular hydrogen-bonding system [3][4][5][6]. The resulting proton-transfer tautomer (keto-form) exhibits considerable differences in molecular structure and electronic configuration from its corresponding ground state, i.e., a large Stokes shifted tautomer fluorescence.…”

Section: Introductionmentioning

confidence: 99%

Synthesis, Crystal Structure, Spectroscopic Properties, and DFT Studies of 7,9-Dibromobenzo[h]quinolin-10-ol

Tsai

Chang

et al. 2017

Crystals

Self Cite

7,9-Dibromobenzo[h]quinolin-10-ol (1), a benzo[h]quinolin-10-ol derivative, was synthesized and characterized by single-crystal X-ray diffraction. The crystal belongs to monoclinic space group P2 1 /n, with a = 3.9573(4), b = 18.0416(18), c = 15.8210(16) Å, α = 90 • , β = 96.139 (3) • , and γ = 90 • . Compound 1 exhibits an intramolecular six-membered-ring hydrogen bond, from which excited-state intramolecular proton transfer takes place, resulting in a proton-transfer tautomer emission of 625 nm in cyclohexane. The crystal structure is stabilized by intermolecular π-π interactions, which links a pair of molecules into a cyclic centrosymmetric dimer. Furthermore, the geometric structures, frontier molecular orbitals, and potential energy curves (PECs) for 1 in the ground and the first singlet excited state were fully rationalized by density functional theory (DFT) and time-dependent DFT calculations.