title: A Lewis acid-mediated conformational switch.
abstract: Molecules that change conformation in response to a stimulus have numerous uses, such as artificial chemoreceptors, novel drug delivery strategies and liquid crystal technology. Here we describe the design, synthesis and conformational behaviour of an isonicotinamide-substituted diphenylacetylene upon recognition of Lewis acids, including metalloporphyrins. Binding of these at a remote site - the pyridyl nitrogen - increases hydrogen-bond donor ability of the proximal amide NH, causing an increased preference for the alkyne rotamer in which this hydrogen bond is maintained.
authors.affiliation: Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford, OX1 3TA, UK. sam.thompson@chem.ox.ac.uk andrew.hamilton@chem.ox.ac.uk.
authors.forename: Peter C
authors.initials: PC
authors.lastname: Knipe
authors.forename: Hannah
authors.initials: H
authors.lastname: Lingard
authors.forename: Ian M
authors.initials: IM
authors.lastname: Jones
authors.forename: Sam
authors.initials: S
authors.lastname: Thompson
authors.forename: Andrew D
authors.initials: AD
authors.lastname: Hamilton