title: Synthesis and ring-chain-ring tautomerism of bisoxazolidines, thiazolidinyloxazolidines, and spirothiazolidines.
abstract: The synthesis of fused heterocycles such as thiazolidinyl-oxazolidine 3 is described starting from Tris·HCl. The mercaptomethyl bisoxazolidine 8 was found to convert to the corresponding thiazolidinyloxazolidine 3 and the spiro-heterocycle 4 by a ring-chain-ring tautomerism, depending on the electronic nature of the ring substituents as well as the reaction conditions. This equilibration pathway is absent in the hydroxymethyl bisoxazolidines 2. Computational studies confirm that both kinetic and thermodynamic control features play a role in the product distribution.
authors.affiliation: Departamento de Química Orgánica, Cátedra de Química Farmacéutica, Universidad de la República (UdelaR), Montevideo, Uruguay.
authors.forename: Cecilia
authors.initials: C
authors.lastname: Saiz
authors.forename: Peter
authors.initials: P
authors.lastname: Wipf
authors.forename: Graciela
authors.initials: G
authors.lastname: Mahler
mesh_terms: D007700:Kinetics; D008968:Molecular Conformation; D010080:Oxazoles / Q000138:chemical synthesis* / Q000737:chemistry; D013237:Stereoisomerism; D013816:Thermodynamics
chemical_list: D010080:Oxazoles; C064210:oxazolidine