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Asymmetric synthesis of anti- and syn-2,3-diamino esters using sulfinimines. Water and concentration effects.

ABSTRACT: [reaction: see text] In the absence of water, an excess of the lithium enolate of N-(diphenylmethylene)glycine ethyl ester (4) adds to sulfinimines to give syn-2,3-diamino esters 6, and in the presence of water, this enolate gives the anti-2,3-diamino esters 5. These unusual results are interpreted in terms of those factors that inhibit the retro-Mannich fragmentation in the diamino esters.

SUBMITTER: Davis FA

PROVIDER: S-EPMC2533706 | biostudies-literature | 2007 Mar

REPOSITORIES: biostudies-literature

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Asymmetric synthesis of anti- and syn-2,3-diamino esters using sulfinimines. Water and concentration effects.

Davis Franklin A FA Zhang Yanfeng Y Qiu Hui H

Organic letters 20070130 5

[reaction: see text] In the absence of water, an excess of the lithium enolate of N-(diphenylmethylene)glycine ethyl ester (4) adds to sulfinimines to give syn-2,3-diamino esters 6, and in the presence of water, this enolate gives the anti-2,3-diamino esters 5. These unusual results are interpreted in terms of those factors that inhibit the retro-Mannich fragmentation in the diamino esters. ...[more]

PMID: 17261004

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