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Synthesis of high enantiopurity N-protected alpha-amino ketones by thiol ester-organostannane cross-coupling using pH-neutral conditions.

ABSTRACT: An efficient synthesis of high enantiopurity N-protected alpha-amino ketones is described. Complementing other studies using boronic acids and thiol esters, this Cu(I) diphenylphosphinate (CuDPP)-mediated, palladium-catalyzed coupling of alpha-amino thiol esters with aryl, heteroaryl, allyl, and alkenyl organostannanes gives N-protected alpha-amino ketones in high yields with high enantiopurity (in almost all cases) under mild and pH-neutral reaction conditions. The viability of pi-deficient heteroarylstannanes is an advantage of this reaction compared to the related boronic acid system.

SUBMITTER: Li H

PROVIDER: S-EPMC2654251 | biostudies-literature | 2008 Oct

REPOSITORIES: biostudies-literature

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Synthesis of high enantiopurity N-protected alpha-amino ketones by thiol ester-organostannane cross-coupling using pH-neutral conditions.

Li Hao H Yang Hao H Liebeskind Lanny S LS

Organic letters 20080830 19

An efficient synthesis of high enantiopurity N-protected alpha-amino ketones is described. Complementing other studies using boronic acids and thiol esters, this Cu(I) diphenylphosphinate (CuDPP)-mediated, palladium-catalyzed coupling of alpha-amino thiol esters with aryl, heteroaryl, allyl, and alkenyl organostannanes gives N-protected alpha-amino ketones in high yields with high enantiopurity (in almost all cases) under mild and pH-neutral reaction conditions. The viability of pi-deficient het ...[more]

PMID: 18759432

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