An analysis of the complementary stereoselective alkylations of imidazolidinone derivatives toward α-quaternary proline-based amino amides

TETRAHEDRON

卷:71

Article

Knight, Brian J.¹  Stache, Erin E.¹  Ferreira, Eric M.¹ 

[1] Univ Georgia, Dept Chem, Athens, GA 30602 USA

关键词: alpha-Quaternary amino amides;    Self-regeneration of stereochemistry;    Imidazolidinones;    Alkylation;    Enolate;   

DOI  :  10.1016/j.tet.2015.05.010

来源: Elsevier

【 摘 要 】

Alkylations of praline-based imidazolidinones are described based on the principle of self-regeneration of stereocenters (SRS), affording high levels of either the cis or trans configured products. Stereoselectivity is dictated solely on the nature of the 'temporary' group, where isobutyraldehyde-derived imidazolidinones provide the cis configured products and 1-naphthaldehyde-derived imidazolidinones afford the complementary trans configured products. These stereodivergent products can be readily cleaved to afford both alpha-alkylated proline enantiomers from readily available L-proline. A series of imidazolidinones were alkylated to investigate the origin of the anti-selectivity. Potential contributions toward the observed anti-selectivity are discussed on the basis of these experiments, suggesting a refined hypothesis for selectivity may be in order. (C) 2015 Elsevier Ltd. All rights reserved.

【 授权许可】

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