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The use of chiral lithium amides in the desymmetrisation of N-trialkylsilyl dimethyl sulfoximines.

ABSTRACT:

Background

Chiral base desymmetrisation of dimethyl sulfoximines could provide a general route to chiral, enantioenriched dialkyl sulfoximines with potential for use in asymmetric catalysis.

Results

Asymmetric deprotonation of N-trialkylsilyl dimethyl sulfoximines with either enantiomer of lithium N,N-bis(1-phenylethyl)amide in the presence of lithium chloride affords enantioenriched sulfoximines on electrophilic trapping. Ketones, ketimines, trialkylsilyl chlorides and activated alkyl halides may be used as electrophiles in the reaction. Furthermore, a modified Horner-Emmons methodology was investigated.

Conclusion

Simple chiral lithium amides afford products with enantiomeric excesses of up to 70%, illustrating that chiral base desymmetrisation of dimethyl sulfoximines is possible.

SUBMITTER: McGrath MJ

PROVIDER: S-EPMC2100055 | biostudies-literature | 2007 Oct

REPOSITORIES: biostudies-literature

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The use of chiral lithium amides in the desymmetrisation of N-trialkylsilyl dimethyl sulfoximines.

McGrath Matthew J MJ Bolm Carsten C

Beilstein journal of organic chemistry 20071016

<h4>Background</h4>Chiral base desymmetrisation of dimethyl sulfoximines could provide a general route to chiral, enantioenriched dialkyl sulfoximines with potential for use in asymmetric catalysis.<h4>Results</h4>Asymmetric deprotonation of N-trialkylsilyl dimethyl sulfoximines with either enantiomer of lithium N,N-bis(1-phenylethyl)amide in the presence of lithium chloride affords enantioenriched sulfoximines on electrophilic trapping. Ketones, ketimines, trialkylsilyl chlorides and activated ...[more]

PMID: 17939868

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