title: Asymmetric catalysis of the [5 + 2] cycloaddition reaction of vinylcyclopropanes and pi-systems.
abstract: As part of our studies of metal-catalyzed [m + n (+...o)] cycloadditions, we have previously reported the rhodium-catalyzed [5 + 2] cycloaddition of vinylcyclopropanes (VCPs) and pi-systems. These studies have led to Rh(I) complexes that catalyze these reactions in minutes at room temperature or in water without organic solvents. We describe a comparative evaluation of several chiral catalysts for the [5 + 2] reaction, evaluation of a preferred catalyst, [((R)-BINAP)Rh]+SbF6-, with substrates differing in substitution and tether types-producing enantiomeric excesses >/=95% for several systems. A predictive model for the selectivity is also presented.
authors: Department of Chemistry, Stanford University, Stanford, California 94305, USA. wenderp@stanford.edu
authors: Paul A
authors: PA
authors: Wender
authors: Lars O
authors: LO
authors: Haustedt
authors: Jaehong
authors: J
authors: Lim
authors: Jennifer A
authors: JA
authors: Love
authors: Travis J
authors: TJ
authors: Williams
authors: Joo-Yong
authors: JY
authors: Yoon