Oxazolidinone cross-alkylation during Evans’ asymmetric alkylation reaction

• Published in: Tetrahedron Vol. 67; no. 47; pp. 9104 - 9111
• Main Authors: Fresno, Nieves, Pérez-Fernández, Ruth, Goya, Pilar, Jimeno, M a Luisa, Alkorta, Ibón, Elguero, José, Menéndez-Taboada, Laura, García-Granda, Santiago
• Format: Journal Article
• Language: English
• Published: OXFORD Elsevier Ltd 25.11.2011; Elsevier
• Subjects: Alkylation; Asymmetric alkylation; Asymmetry; Chemistry; Chemistry, Organic; DFT calculations; Exact sciences and technology; Formations; Fragmentation; Heterocyclic compounds; Heterocyclic compounds with n hetero atom and also o and/or s, se, te hetero atoms; Multinuclear NMR; NMR spectroscopy; Organic chemistry; Oxazolidinone; Physical Sciences; Preparations and properties; Science & Technology; Stereochemistry; Tetrahedrons; X-ray crystallography; X-rays; X-ray crystallography; Multinuclear NMR; Oxazolidinone; Asymmetric alkylation; DFT calculations; H-1-NMR; ESTER TRANSFER PROTEIN; MOLECULAR-ORBITAL METHODS; CHEMICAL-SHIFTS; KARPLUS-TYPE RELATIONSHIPS; NMR; C-13; SCALAR COUPLING-CONSTANTS; RING; AGONIST; Evans alkylation; Theoretical study; NMR spectrometry; X ray diffraction; Asymmetric synthesis; Oxazolidinone derivative; Density functional method; Oxygen nitrogen heterocycle
• ISSN: 0040-4020; 1464-5416
• DOI: 10.1016/j.tet.2011.09.083

Starting from Evans’ imidazolidin-2-one ( 1) two compounds were obtained by trans-N-acylation: the expected one 3 with S, R configuration and a second compound 5, that is, related to 3 by the loss of a CH(CH 3)C O fragment. The stereochemistry of 3 was established by NMR spectroscopy, mainly NOE experiments, as expected, the new center has an S configuration, the compound being thus S, R. The structure of compound 5 was determined by X-ray crystallography. A mechanism of formation of 5 was proposed. [Display omitted]