Control of Acid−Base Properties of New Nanocomposite Derivatives of MCM-36 by Mixed Oxide Pillaring

2004 ◽  
Vol 16 (4) ◽  
pp. 724-730 ◽  
Author(s):  
Jan-Olaf Barth ◽  
Andreas Jentys ◽  
Jan Kornatowski ◽  
Johannes A. Lercher
Keyword(s):  
Mixed Oxide ◽  
Acid Base ◽  
Derivatives Of ◽  
Base Properties

scholarly journals The reactivity of aromatic and heterocyclic derivatives of hydrazine. Vіі. The acid-base properties of substituted 5,7-dichloro-9-hydrazine acridine

2016 ◽  
Vol 0 (1(85)) ◽  
pp. 12-14
Author(s):  
A. O. Deviatkina ◽  
O. M. Svechnikova ◽  
S. V. Kolisnyk ◽  
N. P. Kobzar ◽  
A. F. Vinnyk
Keyword(s):  
Acid Base ◽  
Heterocyclic Derivatives ◽  
Derivatives Of ◽  
Base Properties

Toward novel sulphur-containing derivatives of tetraazacyclododecane: synthesis, acid–base properties, spectroscopic characterization, DFT calculations, and cadmium(ii) complex formation in aqueous solution

2020 ◽  
Vol 44 (20) ◽  
pp. 8337-8350 ◽  
Author(s):  
Marianna Tosato ◽  
Marco Verona ◽  
Riccardo Doro ◽  
Marco Dalla Tiezza ◽  
Laura Orian ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Complex Formation ◽  
Dft Calculations ◽  
Spectroscopic Characterization ◽  
Acid Base ◽  
Derivatives Of ◽  
Base Properties

New sulphur derivatives of cyclen, with potential complementary properties with respect to known compounds, have been synthesized and studied.

scholarly journals SYNTHESIS, COORDINATION AND ACID-BASE PROPERTIES OF MESO-DINITROSUBSTITUTED DERIVATIVES OF 5,15-DIPHENYL-β-OCTAALKYLPORPHINE

2018 ◽  
Vol 61 (6) ◽  
pp. 17
Author(s):  
Svetlana G. Pukhovskaya ◽  
Yulia B. Ivanova ◽  
Dmitry A. Erzunov ◽  
Aleksander S. Semeykin ◽  
Sergei A. Syrbu
Keyword(s):  
Spectral Characteristics ◽  
Spectrophotometric Titration ◽  
Basicity Constant ◽  
Acidity Constant ◽  
Electronic Effects ◽  
Acid Base ◽  
Electronic Effects Of Substituents ◽  
Derivatives Of ◽  
Base Properties

Presented work shows results of synthesis and spectrophotometric researches on properties of meso-dinitrosubstituted derivatives of 5,15-diphenyl-β-octaalkylporphyrin nitroderivatives in comparison with 2,8,12,18,3,7,13,17-octaethylporphyrin and 2,3,7,8,12,13,17,18-octaethyl-5,15-dinitroporphyrin. The method of spectrophotometric titration with perchloric acid (for determining the basicity constant) and 1,8-diazabicyclo [5.4.0] undec-7-ene (DBU) was used in order to study the acid-base properties of porphyrins, namely to determine the acidity constant. The spectral characteristics of the ionized forms of 5,15-dinitro-10,20-diphenyl-3,7,13,17-tetramethyl-2,8,12,18-tetraethylporfin-F (I) and 5,15-dinitro-10,20-bis(4-nitrophenyl)-2,8,12,18-tetramethyl-3,7,13,17-tetraethylporphyrin (II) and the corresponding total constants of the acidic (pKa (I) = 6.00 and pKa (II) = 5.27) and the basic (pKb (I) = 19.78 and pKb (II) = 19.83) ionization were provided. The reaction of complexation of porphyrins with zinc acetate was studied by spectrophotometric method in pure acetonitrile and in mixed AN + DBU solvent. The influence of the degree of deformation of the tetrapyrrole macroring, the electronic effects of substituents and the acidity of the medium on the coordination and acid-base properties of porphyrins was analyzed. It was shown that the reactions of formation of metalloporphyrins with anionic porphyrin forms proceed with much higher rates compared to molecular ones, that is accompanied with a decrease in the energy parameters of the reaction. This is evidently due to the absence of energy costs for the deformation and cleaving N-H bonds of the reaction center, as well as the stronger polarization of the molecule, and as a consequence, the higher degree of solvation of anionic forms of porphyrins in the transition state. Thus, the determination of the conditions for the existence of dianionic forms of porphyrins gives grounds for the development of new sensor systems for the recognition and determination of the concentration of metal cations in liquid media due to a sharp increase in the rate of formation of metalloporphyrins in the presence of an organic base.Forcitation:Pukhovskaya S.G., Ivanova Yu.B., Erzunov D.A., Semeykin A.S., Syrbu S.A. Synthesis, coordination and acid-base properties of meso-dinitrosubstituted derivatives of 5,15-diphenyl-β-octaalkylporphine. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2018. V. 61. N 6. P. 17-28

Tautomerism and Acid-Base Properties of Formyl Derivatives of 1-Phenyl-3-methyl-4,5-dihydropyrazol-5-one and Its Thio Analog

2003 ◽  
Vol 73 (7) ◽  
pp. 1130-1136 ◽  
Author(s):  
A. I. Movchan ◽  
A. R. Kurbangalieva ◽  
O. N. Kataeva ◽  
I. A. Litvinov ◽  
G. A. Chmutova
Keyword(s):  
Acid Base ◽  
Thio Analog ◽  
Derivatives Of ◽  
Base Properties
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