Effect of Structure on Charge Distribution in the Isatin Anions in Aprotic Environment: Spectral Study.
Molecules
; 22(11)2017 Nov 14.
Article
em En
| MEDLINE
| ID: mdl-29135954
ABSTRACT
Five isatin anions were prepared by deprotonation of initial isatins in aprotic solvents using basic fluoride and acetate anions (F- and CH3COO-). The F- basicity is sufficient to deprotonate isatin NH hydrogen from all the studied compounds. This process is reversible. In the presence of proton donor solvents, the anions form the corresponding isatins. The isatin hydrogen acidity depends on the overall structure of the isatin derivatives. The anions were characterized by ultraviolet-visible (UV-Vis), Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopy. Interestingly, the anions form aggregates at concentrations above 10-3 mol·dm-3. Further, the effect of cations on the UV-Vis spectra of the studied anions was studied. Charge transfer and its distribution in the anion depends on the radius and the cation electron configuration. The alkali metal cations, tetrabutylammonium (TBAâº), Mg2+ and Agâº, interact with the C-2 carbonyl oxygen of the isatin anion. The interaction has a coulombic character. On the other hand, Cd2+, Zn2+, Hg2+, Co2+, and Cu⺠cations form a coordinate bond with the isatin nitrogen.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Isatina
/
Ânions
Idioma:
En
Revista:
Molecules
Assunto da revista:
BIOLOGIA
Ano de publicação:
2017
Tipo de documento:
Article
País de afiliação:
Eslováquia