title: Synthesis of planar-chiral paracyclophanes via samarium(II)-catalyzed intramolecular pinacol coupling.
abstract: [reaction: see text] A series of [n]paracyclophanediols (n = 8-12) was synthesized by samarium-catalyzed pinacol coupling for their ansa-bridge formation. Enantiomerically pure [n]paracyclophane esters were derived from the diols in a several steps via chiral resolution (for n = 10) or via crystallization-induced asymmetric transformation (for n = 11) by using amino alcohol auxiliaries and their selective cleavages.
authors.affiliation: Department of Industrial Chemistry, Meiji University, Tama-ku, Kawasaki 214-8571, Japan.
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Ueda
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Kanomata
authors.forename: Hajime
authors.initials: H
authors.lastname: Machida