Kinetics and mechanism of the reactions of the Al13 Keggin oligomer, [AlO4Al12(OH)24(H2O)12]7+, with a series of phenolic ligands

Abstract

The kinetics and mechanism of the reactions of the Keggin oligomer, [AlO₄Al₁₂(OH)₂₄(H₂O)₁₂]⁷⁺ (Al₁₃), with a series of phenol based ligands have been investigated using the stopped-flow technique. Ligands studied include catechol, chlorogenic acid, L-dopa, gallic acid, gallic acid methyl ester, maltol, and salicylic acid. A mechanism is proposed that is consistent with the kinetic data. Formation of the initial bond is the rate determining step and subsequent breakdown of the Al₁₃ oligomer is rapid.