Blanco-Gómez, ArturoNeira, IagoBarriada, José LuisMelle-Franco, ManuelPeinador, CarlosGarcía, Marcos D.2019-12-272019-12-272019-10-23A. Blanco-Gómez, I. Neira, J. L. Barriada, M. Melle-Franco, C. Peinador and M. D. García, Chem. Sci., 2019, 10, 10680–10686.2041-6539http://hdl.handle.net/2183/24551[Abstract] We present herein the development of a new polycationic cyclophane: the “red box”, second in a series of hydrazone-based analogues of the well-known organic receptor cyclobis(paraquat-p-phenylene)cyclophane (“blue box”). The macrocycle has been prepared in an excellent yield in aqueous media, and shows both a remarkable pH-responsiveness and unusual hydrolytic stability of the two hydrazone C[double bond, length as m-dash]N bonds, associated with charge delocalization of the amine lone pair. Whilst in aqueous media the “red box” is able to complex a variety of aromatic substrates, both in its acidic and basic form, in organic media the cyclophane is only able to capture those in the acidic form, resulting in supramolecular pH-responsiveness.engAtribución-NoComercial 3.0 Españahttp://creativecommons.org/licenses/by-nc/3.0/es/Supramolecular chemistryHost-guest chemistryMolecular switchesSupramolecular switchesCyclophanesjournal articleopen access