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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.

SUBMITTER: Saiz C

PROVIDER: S-EPMC3422676 | biostudies-literature | 2011 Jul

REPOSITORIES: biostudies-literature

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Synthesis and ring-chain-ring tautomerism of bisoxazolidines, thiazolidinyloxazolidines, and spirothiazolidines.

Saiz Cecilia C Wipf Peter P Mahler Graciela G

The Journal of organic chemistry 20110614 14

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 ...[more]

PMID: 21634420

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