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Enantioselective Alkylation of 2-Alkylpyridines Controlled by Organolithium Aggregation.

ABSTRACT: Direct enantioselective α-alkylation of 2-alkylpyridines provides access to chiral pyridines via an operationally simple protocol that obviates the need for prefunctionalization or preactivation of the substrate. The alkylation is accomplished using chiral lithium amides as noncovalent stereodirecting auxiliaries. Crystallographic and solution NMR studies provide insight into the structure of well-defined chiral aggregates in which a lithium amide reagent directs asymmetric alkylation.

SUBMITTER: Gladfelder JJ

PROVIDER: S-EPMC7412967 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature

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Enantioselective Alkylation of 2-Alkylpyridines Controlled by Organolithium Aggregation.

Gladfelder Joshua J JJ Ghosh Santanu S Podunavac Maša M Cook Andrew W AW Ma Yun Y Woltornist Ryan A RA Keresztes Ivan I Hayton Trevor W TW Collum David B DB Zakarian Armen A

Journal of the American Chemical Society 20190910 38

Direct enantioselective α-alkylation of 2-alkylpyridines provides access to chiral pyridines via an operationally simple protocol that obviates the need for prefunctionalization or preactivation of the substrate. The alkylation is accomplished using chiral lithium amides as noncovalent stereodirecting auxiliaries. Crystallographic and solution NMR studies provide insight into the structure of well-defined chiral aggregates in which a lithium amide reagent directs asymmetric alkylation. ...[more]

PMID: 31460756

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