title: Ligand anatomy: probing remote substituent effects in asymmetric catalysis through NMR and kinetic analysis.
abstract: A series of structurally related beta-amino alcohols only differing in the steric bulk of a remote alkoxy group exhibit striking differences in kinetic behavior when used as ligands in the asymmetric diethylzinc addition to benzaldehyde (R = Trityl, much more active). A combination of NMR titration studies and kinetic analysis allows the quantitative decomposition of the remote substituent effect into a lower dimerization constant of the active species and a much faster ethyl addition step.
authors.affiliation: Institute of Chemical Research of Catalonia (ICIQ), Av. Països Catalans 16, 43007 Tarragona, Spain.
authors.forename: Ciril
authors.initials: C
authors.lastname: Jimeno
authors.forename: Anton
authors.initials: A
authors.lastname: Vidal-Ferran
authors.forename: Miquel A
authors.initials: MA
authors.lastname: Pericàs