title: A reinvestigation of the reaction between titanium(iv) and salicylic acid in concentrated sulphuric acid.
abstract: It is shown that the coloured species formed between TiO(2+) and salicylic acid in concentrated sulphuric acid may be a pi-complex rather than a chelate. Similar species are formed by other hydroxybenzoic acids where chelating sites for TiO(2+) are not available. The ultraviolet and NMR spectral characteristics of hydroxybenzoic acids in water, concentrated sulphuric acid and deuterochloroform are presented as evidence for the pi-complex formation. The reaction of VO(2+) with salicylic acid in concentrated sulphuric acid is shown to be due to increasing electron-donation in the pi-component of the V-O bond of VO(H(2)O)(5)(2+) as the concentration of sulphuric acid is increased, and not to the presence of salicylic acid.
authors.affiliation: Department of Chemistry, University of Ceylon, Colombo 3, Ceylon.
authors.forename: R S
authors.initials: RS
authors.lastname: Ramakrishna
authors.forename: V
authors.initials: V
authors.lastname: Paramasigamani
authors.forename: M
authors.initials: M
authors.lastname: Mahendran