Chiral sulfoximines

Besides sulfonamides, chiral sulfoximines have also been used in C - N bond formation under microwave irradiation [103]. The only heteroaryl chloride used in the study—namely, 2-chloropyridine—gave the desired M-(pyridin-2-yl)sulfoximine at a yield of 43% (Scheme 101). Interestingly,... 

Gais and co-workers recently reported the preparation and use of chiral sulfoximine-substituted allyltitanium(iv) complexes of type 78 for the asymmetric synthesis of 3-substituted unsaturated proline derivatives 79 (Scheme 31).108... 

Asymmetric elimination with high induction has mainly been described for epoxides, halides and alcohols (using chiral bases), for chiral ketals (using achiral Lewis acids), and for chiral sulfoximines (using achiral bases)1 3. For each compound class only a few examples have been examined, thus, the scope of these methods has not yet been fully explored. The literature on asymmetric eliminations up to 1970 has been covered in a review article4. 

The oxidative imination of sulfides and sulfoxides via nitrene transfer processes leads to N-substituted sulfilimines and sulfoximines. This reaction is interesting as chiral sulfoximines are efficient chiral auxiliaries in asymmetric synthesis, a promising class of chiral ligands for asymmetric catalysis and key intermediates in the synthesis of pseudopeptides [169]. However, very few examples of such iron-catalyzed transformations have been described. 

Chiral sulfoximines liganded to copper(II) give highly enantioselective vinylogous Mukaiyama-type aldol reactions under mild conditions.137 A chiral sulfinyl group has been used to achieve 1,5- and 1,6-asymmetric induction in Mukaiyama aldols, using Yb(OTf)3 catalysis.138... 

This chapter reviews the applications of chiral sulfoximines to asymmetric and diastereoselective synthesis and as ligands in catalytic asymmetric synthesis.1 A number of studies have been performed on racemic substrates but only one enantiomer has been shown to assist the reader. In some schemes the S=N and/or the S=0 bond of the sulfoximine has been shown as a single bond. This is only for reasons of clarity. 

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