title: Four- and Sixfold Tandem-Domino Reactions Leading to Dimeric Tetrasubstituted Alkenes Suitable as Molecular Switches.
abstract: A highly efficient palladium-catalyzed fourfold tandem-domino reaction consisting of two carbopalladation and two C-H-activation steps was developed for the synthesis of two types of tetrasubstituted alkenes 3 and 6 with intrinsic helical chirality starting from substrates 1 and 4, respectively. A sixfold tandem-domino reaction was also developed by including a Sonogashira reaction. 20 compounds with different substitution patterns were prepared with yields of up to 97 %. Structure elucidation by X-ray crystallography confirmed helical chirality of the two alkene moieties. Photophysical investigations of some of the compounds showed pronounced switching properties through light-controlled changes of their stereochemical configuration.
authors.affiliation: Institute of Organic and Biomolecular Chemistry, Georg-August University of Göttingen, Tammannstrasse 2, 37077 Göttingen (Germany). ltietze@gwdg.de.
authors.forename: Lutz F
authors.initials: LF
authors.lastname: Tietze
authors.affiliation: Institute of Organic and Biomolecular Chemistry, Georg-August University of Göttingen, Tammannstrasse 2, 37077 Göttingen (Germany).
authors.forename: Bernd
authors.initials: B
authors.lastname: Waldecker
authors.affiliation: Institute of Organic and Biomolecular Chemistry, Georg-August University of Göttingen, Tammannstrasse 2, 37077 Göttingen (Germany).
authors.forename: Dhandapani
authors.initials: D
authors.lastname: Ganapathy
authors.affiliation: Institute of Organic and Biomolecular Chemistry, Georg-August University of Göttingen, Tammannstrasse 2, 37077 Göttingen (Germany).
authors.forename: Christoph
authors.initials: C
authors.lastname: Eichhorst
authors.affiliation: Physical Chemistry 2, University of Siegen, Adolf-Reichwein-Strasse 2, 57076 Siegen (Germany).
authors.forename: Thomas
authors.initials: T
authors.lastname: Lenzer
authors.affiliation: Physical Chemistry 2, University of Siegen, Adolf-Reichwein-Strasse 2, 57076 Siegen (Germany).
authors.forename: Kawon
authors.initials: K
authors.lastname: Oum
authors.affiliation: Institute of Inorganic Chemistry, Georg-August University of Göttingen, Tammannstrasse 4, 37077 Göttingen (Germany).
authors.forename: Sven O
authors.initials: SO
authors.lastname: Reichmann
authors.affiliation: Institute of Inorganic Chemistry, Georg-August University of Göttingen, Tammannstrasse 4, 37077 Göttingen (Germany).
authors.forename: Dietmar
authors.initials: D
authors.lastname: Stalke
mesh_terms: D000475:Alkenes / Q000737:chemistry*; D002384:Catalysis; D018360:Crystallography, X-Ray; D015394:Molecular Structure; D010165:Palladium / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D000475:Alkenes; D011108:Polymers; D010165:Palladium
keywords: CH activation; domino reactions; helical structures; molecular devices; palladium