Palladium-Catalyzed β-C-H Arylation of Alkyl Carboxamides with Sterically Hindered Aryl Iodides Using ortho-Sulfinyl Aniline Auxiliaries

We disclose a pair of ortho-sulfinylaniline auxiliaries for palladium-catalyzed β-C-H arylation of alkyl carboxamides. Together, these auxiliaries offer a means to effect efficient β-methyl and methylene C-H bond arylation with sterically hindered aryl iodides. ortho-Methylsulfinylaniline (MSOA) enables efficient β-methyl C-H arylation of propanamide substrates with aryl iodides bearing various ortho-substituents including alkyl groups. ortho-Tosylsulfinylaniline (TSOA) enables β-methylene C-H arylation with ortho-substituted aryl iodides. Both amide-linked MSOA and TSOA auxiliaries can be easily removed to give ester products under relatively mild conditions.