title: Ferrocene-based ureas as multisignaling receptors for anions.
abstract: The synthesis of structurally new types of ferrocene-based ureas, in which the ferrocene moiety is simultaneously attached to two urea groups, have been prepared directly from 1,1'-bis(isocyanato)ferrocene 1. Homoditopic receptors 2a-e show spectral and electrochemical anion-sensing action: they display a selective downfield shift of the urea protons and a cathodic shift of the ferrocene/ferrocinium redox couple with hydrogen phosphate and fluoride anions. In addition, receptor 2d based on an unprecedent tetraaza[9]ferrocenophane architecture, shows spectral, electrochemical, and selective fluorescent responses to fluoride anion.
authors.affiliation: Departamento de Química Organica, Facultad de Química, Universidad de Murcia, Campus de Espinardo, E-30100 Murcia, Spain.
authors.forename: Francisco
authors.initials: F
authors.lastname: Otón
authors.forename: Alberto
authors.initials: A
authors.lastname: Tárraga
authors.forename: Arturo
authors.initials: A
authors.lastname: Espinosa
authors.forename: María D
authors.initials: MD
authors.lastname: Velasco
authors.forename: Pedro
authors.initials: P
authors.lastname: Molina