title: Rhodium-catalyzed asymmetric 1,6-addition of aryltitanates to enynones giving axially chiral allenes.
abstract: [reaction: see text] The addition of aryltitanate reagents ArTi(OPr-i)4Li to 3-alkynyl-2-en-1-ones in the presence of chlorotrimethylsilane and a rhodium-(R)-segphos as a catalyst proceeded in a 1,6-fashion to give a high yield of axially chiral allenylalkenyl silyl enol ethers with up to 93% ee.
authors.affiliation: Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo, Kyoto 606-8502, Japan. thayashi@kuchem.kyoto-u.ac.jp
authors.forename: Tamio
authors.initials: T
authors.lastname: Hayashi
authors.forename: Norihito
authors.initials: N
authors.lastname: Tokunaga
authors.forename: Kazuya
authors.initials: K
authors.lastname: Inoue