title: Oxazolidines as Intermediates in the Asymmetric Synthesis of 3-Substituted and 1,3-Disubstituted Tetrahydroisoquinolines.
abstract: A diastereoselective mercury(II)-promoted intramolecular cyclization of unsaturated aldehyde via an oxazolidine to prepare C-3-substituted tetrahydroisoquinoline is disclosed. The C-3 stereogenic center is subsequently exploited to create the C-1 stereocenter by coordination of the nucleophilic reagent to the oxygen atom of oxazolidine. Both cis- and trans-1,3-disubstituted tetrahydroisoquinolines can be readily prepared. In addition, when a cationic rhodium complex was used, intramolecular hydroamination was effected, thus avoiding mercury(II) salts and demercuration. The reaction is general and works well using aliphatic and aromatic aldehydes.
authors.affiliation: Natural Product Chemistry, Indian Institute of Chemical Technology , Hyderabad 500007, India.
authors.forename: Sadagopan
authors.initials: S
authors.lastname: Raghavan
authors.affiliation: Natural Product Chemistry, Indian Institute of Chemical Technology , Hyderabad 500007, India.
authors.forename: Puspamitra
authors.initials: P
authors.lastname: Senapati