Progress Towards the Enantioselective α-Arylation of Amides via Copper (I) Catalysis

Abstract

In this work, I present the ongoing development of a new methodology for the enantioselective coupling of N-acylformamides with diaryliodonium salts mediated by a chiral copper catalyst. This reaction is a development of a related catalytic system for the arylation of N-acyloxazolidinone compounds. Asymmetric arylations of Nacylformamides is a preferable strategy to the corresponding reaction of Nacyloxazolidinones because formamide substrates offer an additional degree of functionalization compared to oxazolidinones, and because fomamides offer direct access to a broader range of derivatives than are accessible from oxazolidinones. These advantages make the α-arylation of N-acylformamides a more powerful tool for introducing tertiary benzylic stereocenters at the α-position of carbonyl compounds than other contemporary methods. The enantioselective α-arylation of N-formyl-Nmethylpropionamide has been demonstrated in moderate yield (50-81%) and enantioselectivity (60-95%) for a small range of para- and meta-substituted iodonium salts. While these results do not fully demonstrate the generality of this transformation, they suggest that the enantioselective arylation of N-acylformamides can be refined to a synthetically useful methodology.