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Vinylaluminum addition to sulfinimines (N-sulfinyl imines). Asymmetric synthesis of anti-alpha-alkyl beta-amino esters.

ABSTRACT: Addition of vinylaluminum NMO reagents to N-(p-toluenesufinyl)- and N-(2-methypropanesulfinyl)-derived sulfinimines gives N-sulfinyl aza-Morita-Baylis-Hillman products (dr = 7:1 to 12:1) that result from addition of the reagent from the least hindered direction. Hydrogenation of the aza-MBH adducts with a Rh(I) catalyst affords anti-alpha-substituted N-sulfinyl-beta-amino esters in good yield and high dr (10:1 to 21:1).

SUBMITTER: Davis FA

PROVIDER: S-EPMC2669707 | biostudies-literature | 2009 Apr

REPOSITORIES: biostudies-literature

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Vinylaluminum addition to sulfinimines (N-sulfinyl imines). Asymmetric synthesis of anti-alpha-alkyl beta-amino esters.

Davis Franklin A FA Qiu Hui H Song Minsoo M Gaddiraju Narendra V NV

The Journal of organic chemistry 20090401 7

Addition of vinylaluminum NMO reagents to N-(p-toluenesufinyl)- and N-(2-methypropanesulfinyl)-derived sulfinimines gives N-sulfinyl aza-Morita-Baylis-Hillman products (dr = 7:1 to 12:1) that result from addition of the reagent from the least hindered direction. Hydrogenation of the aza-MBH adducts with a Rh(I) catalyst affords anti-alpha-substituted N-sulfinyl-beta-amino esters in good yield and high dr (10:1 to 21:1). ...[more]

PMID: 19271739

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