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Regio- and diastereoselective reactions of chiral secondary alkylcopper reagents with propargylic phosphates: preparation of chiral allenes.

ABSTRACT: The diastereoselective S_N2'-substitution of secondary alkylcopper reagents with propargylic phosphates enables the preparation of stereodefined alkylallenes. By using enantiomerically enriched alkylcopper reagents and enantioenriched propargylic phosphates as electrophiles anti-S_N2'-substitutions were performend leading to α-chiral allenes in good yields with excellent regioselectivity and retention of configuration. DFT-calculations were performed to rationalize the structure of these alkylcopper reagents in various solvents, emphasizing their configurational stability in THF.

SUBMITTER: Skotnitzki J

PROVIDER: S-EPMC8159386 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature

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Regio- and diastereoselective reactions of chiral secondary alkylcopper reagents with propargylic phosphates: preparation of chiral allenes.

Skotnitzki Juri J Kremsmair Alexander A Keefer Daniel D Schüppel Franziska F Le Cacher de Bonneville Brieuc B de Vivie-Riedle Regina R Knochel Paul P

Chemical science 20200514 20

The diastereoselective SN2'-substitution of secondary alkylcopper reagents with propargylic phosphates enables the preparation of stereodefined alkylallenes. By using enantiomerically enriched alkylcopper reagents and enantioenriched propargylic phosphates as electrophiles anti-SN2'-substitutions were performend leading to α-chiral allenes in good yields with excellent regioselectivity and retention of configuration. DFT-calculations were performed to rationalize the ...[more]

PMID: 34122991

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