Sulfoximine‐Directed Arene ortho‐Lithiation

Sulfoximines are an interesting class of compounds, which exhibit Brønsted and Lewis basicity, nucleophilicity, C−H acidity, N−H acidity, hydrogen‐bond acceptor capability and chirality. Sulfoximines have received renewed interest in recent times, since incorporation of a sulfoximine group can provide drug candidates with favorable properties. The synthesis and N−H, α ‐C−H and o ‐C−H functionalization of sulfoximines are currently topics of considerable interest. This Minireview describes the sulfoximine‐directed arene ortho ‐lithiation and the synthesis of ortho ‐substituted S‐aryl sulfoximines. Comparison between the sulfoximine and sulfone group shows that both are equally potent directors in arene ortho ‐lithiation. Double ortho ‐lithiation of S‐phenyl sulfoximines affords o , o' ‐dilithiosulfoximines, which undergo a stereoretentive rearrangement to o ‐sulfinylanilines. S‐Phenyl sulfoximines, carrying a α ‐hydrogen atom, are amendable to a selective ortho ‐lithiation to give o ‐lithiosulfoximines, which suffer transmetalation to the α ‐lithiosulfoximines at ambient temperatures. Double lithiation of S‐phenyl N−H sulfoximines gives access to o ,N‐dilithiosulfoximines, the reaction of which with biselectrophiles yields bicyclic sulfoximines.