title: Interaction studies between photochromic spiropyrans and transition metal cations: the curious case of copper.
abstract: A series of four spiropyrans bearing different substituents on the indolic nitrogen were synthesized and their capability of binding mono and bivalent transition metal cations in solution was assessed via UV-visible absorption spectroscopy. All the compounds responded selectively to the presence of Cu(ii) ions producing intense absorption bands in the visible region of their spectra. Bidimensional (1)H-NMR and MALDI-TOF MS spectroscopies revealed the formation of SP dimers mediated by Cu(ii). This is the first example of cross-coupling mediated by copper(ii) in mild conditions causing the symmetric dimerization of spiropyran dyes.
authors.affiliation: Trinity College Dublin, School of Chemistry, College Green, Dublin, 2, Ireland.
authors.forename: Manuel
authors.initials: M
authors.lastname: Natali
authors.forename: Silvia
authors.initials: S
authors.lastname: Giordani
mesh_terms: D001578:Benzopyrans / Q000737:chemistry*; D002412:Cations / Q000737:chemistry; D003300:Copper / Q000737:chemistry*; D007211:Indoles / Q000737:chemistry*; D013058:Mass Spectrometry; D015394:Molecular Structure; D009574:Nitro Compounds / Q000737:chemistry*; D009942:Organometallic Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D055668:Photochemical Processes; D013056:Spectrophotometry, Ultraviolet
chemical_list: D001578:Benzopyrans; D002412:Cations; D007211:Indoles; D009574:Nitro Compounds; D009942:Organometallic Compounds; C088184:spiropyran; D003300:Copper