title: An Autocatalytic System of Photooxidation-Driven Substitution Reactions on a Fe(II)4L6 Cage Framework.
abstract: The functions of life are accomplished by systems exhibiting nonlinear kinetics: autocatalysis, in particular, is integral to the signal amplification that allows for biological information processing. Novel synthetic autocatalytic systems provide a foundation for the design of artificial chemical networks capable of carrying out complex functions. Here we report a set of Fe(II)4L6 cages containing BODIPY chromophores having tuneable photosensitizing properties. Electron-rich anilines were observed to displace electron-deficient anilines at the dynamic-covalent imine bonds of these cages. When iodoaniline residues were incorporated, heavy-atom effects led to enhanced (1)O2 production. The incorporation of (methylthio)aniline residues into a cage allowed for the design of an autocatalytic system: oxidation of the methylthio groups into sulfoxides make them electron-deficient and allows their displacement by iodoanilines, generating a better photocatalyst and accelerating the reaction.
authors.affiliation: Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW (UK).|Current address: Institute of Nano Science and Technology, Habitat Centre, Phase 10, Sector 64, Mohali 160062 (India).
authors.forename: Prakash P
authors.initials: PP
authors.lastname: Neelakandan
authors.affiliation: Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW (UK).|Current address: Department of Chemistry, University of Oviedo, Julian Clavería 8, Oviedo 33006 (Spain).
authors.forename: Azucena
authors.initials: A
authors.lastname: Jiménez
authors.affiliation: Department of Chemistry, Randolph-Macon College, Ashland, VA 23005 (USA).
authors.forename: John D
authors.initials: JD
authors.lastname: Thoburn
authors.affiliation: Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW (UK). jrn34@cam.ac.uk.
authors.forename: Jonathan R
authors.initials: JR
authors.lastname: Nitschke
keywords: autocatalysis; metal-organic capsules; photosensitizers; self-assembly