Pd-catalysed ligand-enabled carboxylate-directed highly regioselective arylation of aliphatic acids.

ABSTRACT: ?-amino acids bearing aromatic side chains are important synthetic units in the synthesis of peptides and natural products. Although various ?-C-H arylation methodologies for amino acid derivatives involving the assistance of directing groups have been extensively developed, syntheses that directly employ N-protected amino acids as starting materials remain rare. Herein, we report an N-acetylglycine-enabled Pd-catalysed carboxylate-directed ?-C(sp3)-H arylation of aliphatic acids. In this way, various non-natural amino acids can be directly prepared from phthaloylalanine in one step in good to excellent yields. Furthermore, a series of aliphatic acids have been shown to be amenable to this transformation, affording ?-arylated propionic acid derivatives in moderate to good yields. More importantly, this ligand-enabled direct ?-C(sp3)-H arylation could be easily scaled-up to 10?g under reflux conditions, highlighting the potential utility of this synthetic method.

SUBMITTER: Zhu Y 

PROVIDER: S-EPMC5384235 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature