title: Comparing the enantioselective power of steric and electrostatic effects in transition-metal-catalyzed asymmetric synthesis.
abstract: The current approach to improve and tune the enantioselective performances of transition-metal catalysts for asymmetric synthesis is mostly focused to modifications of the steric properties of the ancillary ligands of the active metal. Nevertheless, it is also known that electrostatic effects can have a remarkable role to promote selectivity in asymmetric synthesis. Using the Rh-catalyzed asymmetric 1,4-addition of phenylboronic acid to 2-cyclohexenone leading to chiral 3-phenylcyclohexanone as an example, we could show that high enantioselectivity can be indeed achieved using catalysts essentially based either on steric or electrostatic effects as the main source of enantioselective induction. In this contribution we suggest that the analysis of the surface of interaction between the catalyst and the substrate could be a useful tool to quantify the power of steric and electrostatic effects of catalysts.
authors.affiliation: Department of Chemistry, University of Salerno, Via Ponte don Melillo, 84084 Fisciano, Italy.
authors.forename: Albert
authors.initials: A
authors.lastname: Poater
authors.forename: Francesco
authors.initials: F
authors.lastname: Ragone
authors.forename: Ronaldo
authors.initials: R
authors.lastname: Mariz
authors.forename: Reto
authors.initials: R
authors.lastname: Dorta
authors.forename: Luigi
authors.initials: L
authors.lastname: Cavallo
mesh_terms: D001897:Boronic Acids / Q000737:chemistry*; D002384:Catalysis; D003512:Cyclohexanones / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure; D012238:Rhodium / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D001897:Boronic Acids; D003512:Cyclohexanones; C028215:2-cyclohexen-1-one; D012238:Rhodium; C010686:benzeneboronic acid