Nuclear magnetic resonance investigations of azo-hydrazone, acid-base equilibria of FD&C Yellow No. 5 (tartrazine)

Nuclear magnetic resonance investigations of azo-hydrazone, acid-base equilibria of FD&C Yellow No. 5 (tartrazine)

Azo-hydrazone, acid-base equilibria were examined for the water-soluble, food color additive FD Yellow No. 5 (Y5), with the observation of dynamic NMR effects near, and at, pH 10, where the food colorant converts from a predominantly hydrazone tautomer (acidic to moderately basic pH) to a prevailing...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
Veröffentlicht in:Canadian journal of chemistry 1999-11, Vol.77 (11), p.1941-1945
Hauptverfasser: Mazzola, Eugene P., Bell, Sandra J., Turujman, Saleh A., Barrows, Julie N., Bailey, Jr, John E., McMahon, Joseph B., Germann, Tania K., Reynolds, William F.
Format: Artikel
Sprache:eng
Schlagworte:
Acids
Carbon
Food additives
Food dyes
Hydrogen
Isotopes
NMR
Nuclear magnetic resonance
Organic solvents
Online-Zugang:Volltext
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
Beschreibung
Zusammenfassung:Azo-hydrazone, acid-base equilibria were examined for the water-soluble, food color additive FD Yellow No. 5 (Y5), with the observation of dynamic NMR effects near, and at, pH 10, where the food colorant converts from a predominantly hydrazone tautomer (acidic to moderately basic pH) to a prevailing azo-anion resonance hybrid (high pH). Potentiometric titrations further indicate that the pKa of Y5 is ca. 10.
ISSN:0008-4042
1480-3291
DOI:10.1139/cjc-77-11-1941