Asymmetric Synthesis of Amines through Rhodium-Catalyzed C–H Amination with Sulfonimidoylnitrenes
Received: 05. April 2013
Accepted after revision: 27. Mai 2013
27. Juni 2013 (online)
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.
- 1 B.D. and A.J. contributed equally to this work.
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For some recent reviews on the topic, see:
For the first studies involving Rh(II) complexes, see: