Stereoselective Sulfinyl Aniline-Promoted Pd-Catalyzed C-H Arylation and Acetoxylation of Aliphatic Amides.

Stereoselective functionalization of aliphatic C-H bonds presents a great challenge. Following this target, we disclose herein an original strategy towards direct arylation of aliphatic chains at ß-methylene position based on a use of amide-sulfoxide bicoordinating directing group. Although moderate to high chiral induction (up to 9:1 d.r.) is achieved, diastereomerically pure compounds may be afforded by simple separation of diastereomeric products by silica gel chromatography. Accordingly, this reaction allows preparation of a large scope of high-value scaffolds in synthetically useful yields while recyclable character of our chiral auxiliary brings an additional benefit. A potential of this methodology to build up original molecules by sequential diarylation and expedient (two step) synthesis of a biologically active compound are further disclosed. Finally a first example of stereoselective direct acetoxylation of aliphatic chains is reported.
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