title: Stereodivergent synthesis of 1,3-syn- and -anti-tetrahydropyrimidinones.
abstract: An efficient protocol for the stereoselective synthesis of 1,3-syn and -anti-tetrahydropyrimidinones (syn- and anti-11a) is reported. The modular procedure is based on a stereodivergent cyclization of readily available urea-type substrates (10a) by intramolecular allylic substitution. The cyclization proceeds with excellent yield (up to 99%) and selectivity (up to dr > 20:1), purely based on substrate control. The product pyrimidines can be readily transformed into the corresponding free syn- and anti-amines.
authors.affiliation: University of Heidelberg, Department of Organic Chemistry, INF 270, D-69120 Heidelberg, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Morgen
authors.forename: Sebastian
authors.initials: S
authors.lastname: Bretzke
authors.forename: Pengfei
authors.initials: P
authors.lastname: Li
authors.forename: Dirk
authors.initials: D
authors.lastname: Menche
mesh_terms: D003500:Cyclization; D015394:Molecular Structure; D011744:Pyrimidinones / Q000138:chemical synthesis*; D013237:Stereoisomerism; D014508:Urea / Q000737:chemistry
chemical_list: D011744:Pyrimidinones; C505709:tetrahydropyrimidinone; D014508:Urea