A highly selective visual and fluorescent sensor for Pb2+ and Zn2+ and crystal structure of Cu2+ complex based-on a novel single-armed Salamo-type bisoxime

A novel single-armed Salamo-type bisoximes (H4L) has been designed and synthesised. An obvious colour change from yellow (H4L) to pale pink (HL-Pb2+) which can be visually observed by the naked eye in visible light. H4L can act as a fluorescent sensor for ratiometric recognition of Zn2+ with high selectivity and sensitivity. Crystallographic data of the [Cu(HL)(μ-OAc)Cu] reveals that the two Cu2+ ions are both penta-coordinated with square pyramidal geometries, and forms a 2D supramolecular plane structure by hydrogen bonding interactions.