Enantioselective Synthesis of Dialkylated α‐Hydroxy Carboxylic Acids Through Asymmetric Phase‐Transfer Catalysis.

The enantioselective alkylation of 5H-oxazol-4-ones in the presence of an amino acid-derived urea catalyst (TLU) gives rise to desired 5-dialkylated oxazolones such as (III) and (VI).