Asymmetric Synthesis of Amines through Rhodium-Catalyzed C–H Amination with Sulfonimidoylnitrenes

Abstract

An efficient asymmetric C–H amination of benzylic and allylic substrates, as well as of adamantane derivatives, through catalytic C–H insertion of a chiral nitrene is reported. The reaction involves a chiral rhodium(II) complex, an iodine(III) oxidant, and a sulfonimid­amide as a nitrene precursor. Experimental protocols for the preparation of the reagents and the catalytic nitrene are provided. The C–H amination can provide the corresponding amino derivatives on a gram scale. Various methods for the cleavage of the sulfonimidoyl group to give the corresponding tert-butoxycarbonyl- or acetyl-protected optically pure amines are also described.

Key words

rhodium - amines - nitrene - asymmetric catalysis - C–H amination

• References

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