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

ABSTRACT: Alkylations of proline-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 ?-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.

SUBMITTER: Knight BJ

PROVIDER: S-EPMC6241292 | biostudies-literature | 2015 Sep

REPOSITORIES: biostudies-literature

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

Knight Brian J BJ Stache Erin E EE Ferreira Eric M EM

Tetrahedron 20150509 35

Alkylations of proline-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 stereodiv ...[more]

PMID: 30464358

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