Amination of β-hydroxyl acid esters via cooperative catalysis enables access to bio-based β-amino acid esters

Abstract

β-amino acid esters are important scaffolds in medicinal chemistry and valuable building blocks for materials synthesis. Surprisingly, the waste-free construction of such moieties from readily available or renewable starting materials has not yet been addressed. Here we report on a robust and versatile method for obtaining β-amino acid esters by direct amination of β-hydroxyl acid esters via the borrowing hydrogen methodology using a cooperative catalytic system that comprises a homogeneous ruthenium catalyst and an appropriate Brønsted acid additive. This method allows for the direct amination of esters of 3-hydroxypropionic acid, a top value-added bio-based platform chemical, opening a simple route to access β-amino acid esters from a range of renewable polyols including sugars and glycerol.