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Evans Enolates: Solution Structures of Lithiated Oxazolidinone-Derived Enolates.

ABSTRACT: The results of a combination of (6)Li and (13)C NMR spectroscopic and computational studies of oxazolidinone-based lithium enolates-Evans enolates-in tetrahydrofuran (THF) solution revealed a mixture of dimers, tetramers, and oligomers (possibly ladders). The distribution depended on the structure of the oxazolidinone auxiliary, substituent on the enolate, and THF concentration (in THF/toluene mixtures). The unsolvated tetrameric form contained a D(2d)-symmetric core structure, whereas the dimers were determined experimentally and computationally to be trisolvates with several isomeric forms.

SUBMITTER: Tallmadge EH

PROVIDER: S-EPMC4765922 | biostudies-literature | 2015 Oct

REPOSITORIES: biostudies-literature

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Evans Enolates: Solution Structures of Lithiated Oxazolidinone-Derived Enolates.

Tallmadge Evan H EH Collum David B DB

Journal of the American Chemical Society 20151005 40

The results of a combination of (6)Li and (13)C NMR spectroscopic and computational studies of oxazolidinone-based lithium enolates-Evans enolates-in tetrahydrofuran (THF) solution revealed a mixture of dimers, tetramers, and oligomers (possibly ladders). The distribution depended on the structure of the oxazolidinone auxiliary, substituent on the enolate, and THF concentration (in THF/toluene mixtures). The unsolvated tetrameric form contained a D(2d)-symmetric core structure, whereas the dimer ...[more]

PMID: 26437278

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