title: Highly enantioselective Rh2(S-DOSP)4-catalyzed cyclopropenation of alkynes with styryldiazoacetates.
abstract: Dirhodium tetrakis((S)-N-(dodecylbenzenesulfonyl)prolinate) (Rh2(S-DOSP)4) is an effective catalyst for highly enantioselective cyclopropenation reactions between terminal alkynes and arylvinyldiazoacetates. The resulting vinylcyclopropenes can undergo rhodium-catalyzed regioselective rearrangement to cyclopentadienes. Computational studies indicate that the high enantioselectivity of the process is governed by the specific orientation of the alkyne during its approach to the carbenoid through a relatively late transition state. The specific orientation occurs due to the presence of a hydrogen bonding interaction between the alkyne hydrogen and a carboxylate ligand on the dirhodium catalyst.
authors.affiliation: Department of Chemistry, Emory University, 1515 Dickey Drive, Atlanta, Georgia 30322, USA.
authors.forename: John F
authors.initials: JF
authors.lastname: Briones
authors.forename: Jørn
authors.initials: J
authors.lastname: Hansen
authors.forename: Kenneth I
authors.initials: KI
authors.lastname: Hardcastle
authors.forename: Jochen
authors.initials: J
authors.lastname: Autschbach
authors.forename: Huw M L
authors.initials: HM
authors.lastname: Davies