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Diastereo- and Enantioselective Synthesis of Homoallylic Amines Bearing Quaternary Carbon Centers.

ABSTRACT: A Cu-catalyzed method for the efficient enantio- and diastereoselective synthesis of chiral homoallylic amines bearing a quaternary carbon and an alkenylboron is disclosed. Transformations are promoted by a readily prepared (phosphoramidite)-Cu complex and involve bench-stable ?,?-disubstituted allyldiborons and benzyl imines; products are obtained in up to 82% yield, >20:1 dr, and >99:1 er. Reactions proceed via stereodefined boron-stabilized allylic Cu species formed by an enantioselective transmetalation. Utility of the 1-amino-3-alkenylboronate products is highlighted by a variety of synthetic transformations.

SUBMITTER: Green JC

PROVIDER: S-EPMC7180160 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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Diastereo- and Enantioselective Synthesis of Homoallylic Amines Bearing Quaternary Carbon Centers.

Green Jacob C JC Zanghi Joseph M JM Meek Simon J SJ

Journal of the American Chemical Society 20200117 4

A Cu-catalyzed method for the efficient enantio- and diastereoselective synthesis of chiral homoallylic amines bearing a quaternary carbon and an alkenylboron is disclosed. Transformations are promoted by a readily prepared (phosphoramidite)-Cu complex and involve bench-stable γ,γ-disubstituted allyldiborons and benzyl imines; products are obtained in up to 82% yield, >20:1 dr, and >99:1 er. Reactions proceed via stereodefined boron-stabilized allylic Cu species formed by an enantioselective tra ...[more]

PMID: 31934766

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