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A highly stereoselective addition of lithiated ynamides to Ellman-Davis chiral N-tert-butanesulfinyl imines.

ABSTRACT: A highly diastereoselective addition of lithiated ynamides to Ellman-Davis chiral imines is described. While additions of N-sulfonyl ynamides are highly stereoselective even without Lewis acids, the use of BF3-OEt2 completely reversed the stereoselectivity. In addition, oxazolidinone-substituted ynamides behaved differently and functioned better with BF3-OEt2, and the chirality of the oxazolidinone ring exerts no impact on the selectivity.

SUBMITTER: Wang XN

PROVIDER: S-EPMC3759603 | biostudies-literature | 2013 May

REPOSITORIES: biostudies-literature

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A highly stereoselective addition of lithiated ynamides to Ellman-Davis chiral N-tert-butanesulfinyl imines.

Wang Xiao-Na XN Hsung Richard P RP Qi Rui R Fox Sierra K SK Lv Ming-Can MC

Organic letters 20130506 10

A highly diastereoselective addition of lithiated ynamides to Ellman-Davis chiral imines is described. While additions of N-sulfonyl ynamides are highly stereoselective even without Lewis acids, the use of BF3-OEt2 completely reversed the stereoselectivity. In addition, oxazolidinone-substituted ynamides behaved differently and functioned better with BF3-OEt2, and the chirality of the oxazolidinone ring exerts no impact on the selectivity. ...[more]

PMID: 23646900

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