Diazo-Coupling Reactions with Calix[4]arene. pKa Determination with Chromophoric Azocalix[4]arenes
Authors:
- 1 June 1989
- journal article
- Published by Oxford University Press (OUP) in Chemistry Letters
- Vol. 18 (6) , 931-934
Abstract
Six azocalix[4]arenes were synthesized for the first time by diazo-coupling reactions with calix[4]arene. The products showed unusual spectral properties including an azophenol–quinine–hydrazone tautomerism. Owing to the chromophoric nature, the four pKa’s for water-soluble p-(4-trimethylammoniopheylazo)calix[4]arene could be determined to be 0.5, 2.0, 10.0, and ca. 13. The marked pKa split was explained by the strong hydrogen-bonding interactions characteristic of calix[4]arene.Keywords
This publication has 6 references indexed in Scilit:
- Conformational and complexational characteristics of calixarenesPure and Applied Chemistry, 1988
- Calixarenes as new functionalized host moleculesPure and Applied Chemistry, 1986
- Calixarenes. 13. The conformational properties of calix[4]arenes, calix[6]arenes, calix[8]arenes, and oxacalixarenesJournal of the American Chemical Society, 1985
- CalixarenesAccounts of Chemical Research, 1983
- Studies on coupling reactions of 1-naphthol. 6. Tautomerism and dissociation of 4-arylazo-1-naphthols in various solventsThe Journal of Organic Chemistry, 1978
- Keto-Enol Tautomerism of Azo DyesJournal of Synthetic Organic Chemistry, Japan, 1969