title: π-Helicenes truncated to a minimum: access through a domino approach involving multiple carbopalladations and a Stille coupling.
abstract: A novel type of π-helicenes is reported, in which the π-system is truncated to an all-s-cis all-Z oligoene chain. A domino sequence was developed, consisting of up to four consecutive carbopalladation reactions and a terminal Stille cross-coupling, to generate these entities in one step from the respective linear oligoynes. Despite the minimal π-system, very high optical rotation values were encountered for the single enantiomers. X-ray crystallography confirmed their screw-shaped structure.
authors.affiliation: Technische Universität Braunschweig, Institut für Organische Chemie, Hagenring 30, 38106 Braunschweig (Germany) http://www.werzlab.de.
authors.forename: Bastian
authors.initials: B
authors.lastname: Milde
authors.forename: Markus
authors.initials: M
authors.lastname: Leibeling
authors.forename: Martin
authors.initials: M
authors.lastname: Pawliczek
authors.forename: Jörg
authors.initials: J
authors.lastname: Grunenberg
authors.forename: Peter G
authors.initials: PG
authors.lastname: Jones
authors.forename: Daniel B
authors.initials: DB
authors.lastname: Werz
keywords: carbopalladation; domino reaction; helicenes