title: Helical twist sense bias in oligo(phenylene ethynylene)s induced by an optically active flexible tether
abstract: [graph and structure: see text] A series of tethered phenylene ethynylene oligomers, which undergo a solvent-dependent conformational transition from a random coil to a helix, has been synthesized. The use of trimethylsilyl ether protecting groups on the (+)-tartaric acid-derived tether results in the formation of helices with a large twist sense bias. In contrast, an isopropylidene ketal protecting group or no protecting group is not only ineffective at helical discrimination but may even inhibit helix formation.
authors.affiliation: Department of Chemistry, The University of Illinois at Urbana-Champaign, Urbana 61801, USA.
authors.initials: MS
authors.lastname: Gin
authors.initials: JS
authors.lastname: Moore