title: The role of β-bulky substituents in aldol reactions of boron enolates of methylketones with aldehydes: experimental and theoretical studies by DFT analysis.
abstract: In this work, we show the influence of the volume of the β-substituents on the levels of 1,5-stereoselectivities of aldol reactions of boron enolates generated from β-alkoxy methylketones with aldehydes. Excellent levels of 1,5-syn stereoinduction were obtained when the β-protecting group is a silicon ether. This remarkable selectivity is attributed to the volume of the β-bulky substituent of the corresponding boron enolate. We have investigated a stereochemical model using DFT analysis to rationalize the sense of 1,5-syn stereoselectivities of β-alkyl-β-alkoxy methylketones.
authors.affiliation: Chemistry Institute, State University of Campinas, UNICAMP, 13083-970, C.P. 6154, Campinas, SP, Brazil. ldias@iqm.unicamp.br
authors.forename: Luiz C
authors.initials: LC
authors.lastname: Dias
authors.forename: Emílio C
authors.initials: EC
authors.lastname: de Lucca
authors.forename: Marco A B
authors.initials: MA
authors.lastname: Ferreira
authors.forename: Danilo C
authors.initials: DC
authors.lastname: Garcia
authors.forename: Cláudio F
authors.initials: CF
authors.lastname: Tormena