School of Chemistry and EaStCHEM, Un Andrews, Fife KY16 9ST, UK. E-mail: d.ph 463808; Tel: +44 (0)1334 467264 Institut de Génétique et de Biologie Molécu UMR 7104, Université de Strasbourg, Graffenstaden, France † Electronic supplementary information ( methods, synthesis and characterisation CCDC 1442418–1442421. For ESI and c electronic format see DOI: 10.1039/c6sc01 Cite this: Chem. Sci., 201...