Hydrolytic Metalloenzyme Models. Metal Ion Dependent Site-selective Acylations of Hydroxyl Groups of Bis-imidazole Ligands Promoted by Zn2+ and Cu2+ Ions in Cationic Micelles

Abstract
Co-micelles of cetyltrimethylammonium bromide and lipophilic bis-imidazole ligands having primary and secondary hydroxyl groups in their side chains were investigated for their catalytic activities in the hydrolysis of p-nitrophenyl picolinate in the presence of Zn2+ and Cu2+ at 25 °C. The kinetic and product analyses strongly suggested that the site-selective acylation of hydroxyl groups of ligands occurs via the formation of a tetrahedral for Zn2+ ion and a square planar complex for Cu2+ ion.