title: Temperature- and time-dependent stereochemical control in thermally induced keto-ene cyclizations.
abstract: Reaction conditions determine the stereoselection in the intramolecular keto-ene reaction. The thermolysis of chiral 2-acyl-3-allyl-substituted 1,3-perhydrobenzoxazines derived from (-)-8-aminomenthol gives a mixture of only two cis-3-hydroxy-3,4-disubstituted pyrrolidine nuclei. The stereochemistry of the major diastereoisomer depends on both the temperature and the reaction time.
authors.affiliation: Departamento de Química Orgánica, Facultad de Ciencias, Universidad de Valladolid, Dr. Mergelina s/n, 47011-Valladolid, Spain. pedrosa@qo.uva.es
authors.forename: Rafael
authors.initials: R
authors.lastname: Pedrosa
authors.forename: Celia
authors.initials: C
authors.lastname: Andrés
authors.forename: Carlos D
authors.initials: CD
authors.lastname: Rosón
authors.forename: Martina
authors.initials: M
authors.lastname: Vicente