title: Highly stereoselective aldol reaction based on titanium enolates from (S)-1-benzyloxy-2-methyl-3-pentanone.
abstract: Alternative titanium-mediated aldol procedures based on several protected beta-hydroxy ethyl ketones have been surveyed. Eventually, enolization of (S)-1-benzyloxy-2-methyl-3-pentanone (1) with (i-PrO)TiCl3/i-Pr2NEt provided a very reactive enolate that afforded the corresponding 2,4-syn-4,5-syn aldol adducts in high yields and diastereomeric ratios with a broad range of aldehydes.
authors.affiliation: Departament de Química Orgànica, Universitat de Barcelona, Martí i Franqués 1-11, 08028 Barcelona, Catalonia, Spain.
authors.forename: Joan G
authors.initials: JG
authors.lastname: Solsona
authors.forename: Joaquim
authors.initials: J
authors.lastname: Nebot
authors.forename: Pedro
authors.initials: P
authors.lastname: Romea
authors.forename: Fèlix
authors.initials: F
authors.lastname: Urpí