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Practical and highly enantioselective synthesis of beta-alkynyl-beta-amino esters through Ag-catalyzed asymmetric mannich reactions of silylketene acetals and alkynyl imines.

ABSTRACT: [reaction: see text] A readily available iso-leucine-based phosphine ligand is used to promote Ag-catalyzed Mannich reactions between silylketene acetals and various alkynyl imines. Reactions can be effected in the presence of 5 mol % catalyst, without the need for rigorous exclusion of air, and with commercially available solvents (without purification) to afford the desired beta-alkynyl-beta-amino esters in 84-94% ee and 61-91% isolated yield.

SUBMITTER: Josephsohn NS

PROVIDER: S-EPMC2597397 | biostudies-literature | 2005 Jun

REPOSITORIES: biostudies-literature

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Practical and highly enantioselective synthesis of beta-alkynyl-beta-amino esters through Ag-catalyzed asymmetric mannich reactions of silylketene acetals and alkynyl imines.

Josephsohn Nathan S NS Carswell Emma L EL Snapper Marc L ML Hoveyda Amir H AH

Organic letters 20050601 13

[reaction: see text] A readily available iso-leucine-based phosphine ligand is used to promote Ag-catalyzed Mannich reactions between silylketene acetals and various alkynyl imines. Reactions can be effected in the presence of 5 mol % catalyst, without the need for rigorous exclusion of air, and with commercially available solvents (without purification) to afford the desired beta-alkynyl-beta-amino esters in 84-94% ee and 61-91% isolated yield. ...[more]

PMID: 15957928

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