title: Metal 'turn-off', anion 'turn-on' gelation cascade in pyridinylmethyl ureas.
abstract: Pyridinylmethyl ureas form strong gels in aromatic solvents. The gels are weakened or destroyed by addition of transition metal ions but gelation is recovered by adding bromide anions giving rise to a gel-sol-gel chemically triggered cascade.
authors.affiliation: Department of Chemistry, Durham University, University Science Laboratories, South Road, Durham, DH1 3LE, UK. jon.steed@durham.ac.uk.
authors.forename: Caroline A
authors.initials: CA
authors.lastname: Offiler
authors.affiliation: Department of Chemistry, Durham University, University Science Laboratories, South Road, Durham, DH1 3LE, UK. jon.steed@durham.ac.uk.
authors.forename: Christopher D
authors.initials: CD
authors.lastname: Jones
authors.affiliation: Department of Chemistry, Durham University, University Science Laboratories, South Road, Durham, DH1 3LE, UK. jon.steed@durham.ac.uk.
authors.forename: Jonathan W
authors.identifier: http://orcid.org/0000-0002-7466-7794
authors.initials: JW
authors.lastname: Steed